BỘ GIÁO DỤC VÀ ĐÀO TẠO BỘ Y TẾ
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BỘ GIÁO DỤC VÀ ĐÀO TẠO BỘ Y TẾ TRƢỜNG ĐẠI HỌC Y HÀ NỘI HÀ HỮU TÙNG NGHIÊN CỨU THỰC TRẠNG MÔI TRƢỜNG, SỨC KHỎE CỦA NGƢỜI CHĂN NUÔI GIA CẦM VÀ GIẢI PHÁP CAN THIỆP TẠI HUYỆN PHÚ XUYÊN, HÀ NỘI LUẬN ÁN TIẾN SĨ Y HỌC HÀ NỘI - 2013
Transcript of BỘ GIÁO DỤC VÀ ĐÀO TẠO BỘ Y TẾ
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B GIO DC V O TO B Y T
TRNG I HC Y H NI
H HU TNG
NGHIN CU THC TRNG MI TRNG,
SC KHE CA NGI CHN NUI GIA CM
V GII PHP CAN THIP
TI HUYN PH XUYN, H NI
LUN N TIN S Y HC
H NI - 2013
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B GIO DC V O TO B Y T
TRNG I HC Y H NI
H HU TNG
NGHIN CU THC TRNG MI TRNG,
SC KHE CA NGI CHN NUI GIA CM
V GII PHP CAN THIP
TI HUYN PH XUYN, H NI
Chuyn ngnh : Y T Cng Cng
M s : 62.72.76. 01
LUN N TIN S Y HC
Ngi hng dn khoa hc:
PGS.TS. Nguyn Th Bch Lin
TS. Hong Th Minh Hin
H NI - 2013
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LI CAM OAN
Ti xin cam oan cng trnh nghin cu ny do chnh ti thc hin.
Cc s liu, kt qu trong nghin cu l trung thc v cha c ai cng b
trong bt k cng trnh nghin cu no khc.
Tc gi
H Hu Tng
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LI CM N
Ti xin gi li cm n chn thnh ti Ban Gim Hiu Trng i hc
Y H Ni, Vin o to Y hc d phng v Y t Cng cng, cc B mn lin
quan, Phng o to sau i hc to iu kin thun li nht cho ti trong
sut qu trnh hc tp v hon thnh Lun n.
Ti xin by t lng bit n chn thnh v su sc ti PGS - TS Nguyn
Th Bch Lin, TS. Hong Th Minh Hin, nhng ngi thy tm huyt tn
tnh gip , hng dn; xin cm n ti Ph gio s - Tin s ch nhim B
mn Sc khe ngh nghip ng vin khch l, dnh nhiu thi gian trao
i v nh hng cho ti trong qu trnh thc hin Lun n.
Nhn dp ny ti xin chn thnh cm n Bnh vin Nng nghip, ni
ti ang cng tc, to iu kin gip ti trong sut qu trnh hc tp v
nghin cu, c bit l trong thi gian trin khai nghin cu ti thc a.
Xin chn thnh cm n x Hng Thi, x i Xuyn - huyn Ph
Xuyn; Vin Y hc lao ng v V sinh mi trng Trung ng to iu
kin gip ti trong qu trnh trin khai nghin cu, thu thp s liu v trin
khai can thip hon thnh Lun n.
Cui cng, ti xin chn thnh cm n gia nh, bn b, ng nghip
ng vin, khuyn khch ti trong sut qu trnh hc tp v nghin cu.
Xin chn thnh cm n!
Tc gi Lun n
H Hu Tng
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DANH MC CC T VIT TT
BNN : B Nng nghip v Pht trin Nng thn
BTNMT : B Ti nguyn mi trng
BVTV : Bo v thc vt
BHL : Bo h lao ng
CS : Cng s
CGC : Cm gia cm
KMT : iu kin mi trng
FAO : (Food and Agriculture Organization of the United Nations):
T chc Nng lng, lng thc th gii.
HCBVTV : Ha cht bo v thc vt
HG : H gia nh
HQCT : Hiu qu can thip
ILO : (International Labour Organization) T chc lao ng quc t ODTS
(Organic dust toxic syndrome): Hi chng nhim c bi hu c
QCVN : Qui chun Vit Nam
TCVSCP : Tiu chun v sinh cho php
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MC LC
T VN ................................................................................................... 1
Chng 1: TNG QUAN ................................................................................ 3
1.1. Thc trng mi trng chn nui gia cm v sc khe ca ngi lao
ng chn nui gia cm ........................................................................ 3
1.1.1. Thc trng iu kin - mi trng chn nui gia cm ................... 3
1.1.2. Thc trng v sc kho ca ngi lao ng chn nui gia cm ..... 5
1.1.3. Thc trng cng tc bo v mi trng trong ngnh nng nghip .... 6
1.2. C s l thuyt lin quan n mi trng v nhng nh hng ca
chng ti sc khe ca ngi chn nui gia cm ................................. 7
1.2.1. H chn nui gia cm ..................................................................... 7
1.2.2. Mi trng ...................................................................................... 7
1.2.3. Yu t tc hi ngh nghip trong chn nui gia cm v nh
hng ca chng ti sc khe ngi lao ng ........................... 11
1.2.4. Cc bnh gy ra do tip xc trc tip vi mi trng chn
nui gia cm ................................................................................. 15
1.2.5. Bnh do vi sinh vt ....................................................................... 16
1.2.6. Bnh ngh nghip v nhng bnh lin quan ti ngh nghip ...... 18
1.3. Nhng nghin cu v nh hng ca iu kin mi trng chn
nui gia cm ti sc khe ngi lao ng .......................................... 19
1.3.1. Nhng nghin cu v nh hng ca KMT chn nui gia cm
ti sc khe ngi lao ng trn th gii ..................................... 19
1.3.2. Nhng nghin cu v nh hng ca iu kin mi trng chn
nui gia cm ti sc khe ngi lao ng ti Vit Nam .............. 23
1.4. Cc gii php ci thin mi trng nng cao sc khe ca ngi
chn nui gia cm ................................................................................ 28
1.4.1. Cc gii php ci thin mi trng chn nui gia cm trn
th gii ......................................................................................... 28
1.4.2. Cc gii php ci thin mi trng chn nui gia cm ti
Vit nam ....................................................................................... 28
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1.5. c im kinh t, vn ha x hi, chn nui gia cm huyn
Ph Xuyn .......................................................................................... 30
Chng 2: I TNG V PHNG PHP NGHIN CU .............. 32
2.1. i tng nghin cu .......................................................................... 32
2.2. a im nghin cu ............................................................................ 33
2.3. Phng php nghin cu ...................................................................... 34
2.3.1. Thit k nghin cu ....................................................................... 34
2.3.2. Giai on 1 .................................................................................... 35
2.3.3. Giai on 2 .................................................................................... 43
2.3.4. Khng ch sai s trong nghin cu ............................................... 47
2.3.5. Mt s khi nim s dng trong nghin cu ................................ 48
2.3.6. o c nghin cu ...................................................................... 48
2.3.7. Hn ch ca ti ......................................................................... 48
Chng 3: KT QU NGHIN CU ......................................................... 50
3.1. Thng tin chung v cc thnh vin thuc cc h gia nh tham gia
nghin cu ........................................................................................... 50
3.2. Thc trng mi trng lm vic, sc kho, kin thc, thc hnh
phng bnh ca ngi chn nui gia cm ........................................... 52
3.2.1. Thc trng cc yu t mi trng ti cc chung/tri chn nui
gia cm .......................................................................................... 52
3.2.2. iu kin chn nui v v sinh chung/ tri gia cm .................. 55
3.2.3. Kt qu phng vn ngi trc tip chn nui gia cm (n = 185) 60
3.2.4. Thc trng sc khe ca cc i tng nghin cu v cc thnh
vin trong cc h gia nh nghin cu ......................................... 69
3.3. Hiu qu can thip gio dc truyn thng ........................................... 72
3.3.1. Hiu qu can thip thay i iu kin mi trng chn nui
gia cm ......................................................................................... 72
3.3.2. Hiu qu can thip thay i kin thc, thc hnh ........................ 77
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Chng 4: BN LUN .................................................................................. 85
4.1. c im chung ca i tng nghin cu ......................................... 85
4.2. Thc trng mt s yu t mi trng, sc kho, kin thc, thc
hnh phng bnh ca ngi chn nui gia cm .................................. 87
4.2.1. Thc trng mt s ch s v v sinh chn nui ............................ 87
4.2.2. iu kin chn nui v v sinh chung tri nui gia cm ........... 91
4.2.3. Kin thc v thc hnh v v sinh chn nui ............................... 96
4.2.4. Tnh hnh sc khe v bnh tt ca con ngi lin quan n
mi trng chn nui gia cm .................................................... 101
4.3. Hiu qu can thip gio dc truyn thng thay i kin thc, thc
hnh v iu kin v sinh chung tri chn nui gia cm ................ 105
4.3.1. Ci thin v iu kin chung/tri v v sinh mi trng
chung nui ................................................................................ 105
4.3.2. Ci thin v kin thc, thc hnh v v sinh chn nui v s
dng phng h lao ng ............................................................. 107
4.3.3. Ci thin v hiu bit bnh tt v sc khe ca con ngi lin
quan n chn nui gia cm ....................................................... 111
4.4. Vn qun l lin quan n ngnh ngh ......................................... 113
KT LUN ................................................................................................... 116
KIN NGH .................................................................................................. 118
TI LIU THAM KHO
PH LC
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DANH MC BNG
Bng 1.1: Cc c t nm mc c pht hin ........................................... 15
Bng 2.1: Phn b s thnh vin trong 90 h gia nh nghin cu hai x
la chn (i Xuyn, Hng Thi) theo quan h vi ch h ....... 37
Bng 2.2: Phn b s h gia nh ca 2 x c chn vo nghin cu
theo thn ..................................................................................... 39
Bng 2.3: Tiu chun nm mc trong khng kh theo Romanovic ............. 40
Bng 2.4: Tiu chun cht lng khng kh trong nh ca Safir ................ 40
Bng 2.5: nh gi ch s khi c th theo chun ca T chc Y t Th
gii (WHO) ....................................... 42
Bng 3.1: Phn b cc thnh vin h gia nh theo nhm tui ................... 51
Bng 3.2: Phn b cc thnh vin thuc h gia nh theo trnh hc vn 51
Bng 3.3: Kt qu o vi kh hu ti chung/tri chn nui gia cm 2 x
nghin cu ................................................................................... 52
Bng 3.4: Kt qu nh lng cc hi kh c ti chung/ tri chn nui gia
cm ca 2 x nghin cu ............................................................. 53
Bng 3.5: Kt qu xt nghim cc yu t vi sinh vt ti mi trng khng
kh chung/ tri chn nui gia cm (/m3 khng kh) ................... 54
Bng 3.6: Phng thc nui gia cm ca cc h gia nh ........................... 55
Bng 3.7: Phn b t l khong cch t chung/ tri nui gia cm ti nh
ca cc h gia nh nghin cu ................................................... 56
Bng 3.8: Phn b t l cc khong cch t chung/tri nui gia cm ti bp
ca cc h gia nh nghin cu ................................................... 57
Bng 3.9: Phn b t l cc khong cch t chung/ tri nui gia cm ti
ging nc, b cha nc n ca cc h gia nh nghin cu.... 57
Bng 3.10: Phn b t l cc loi chung/ tri nui gia cm ca cc h gia
nh nghin cu ........................................................................... 58
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Bng 3.11: Tnh trng v sinh chung tri nui gia cm ti cc h gia nh
nghin cu ................................................................................... 59
Bng 3.12: Tnh trng mi trng xung quanh chung tri nui gia cm .... 59
Bng 3.13: T l h gia nh c ni cha nc thi v sinh ......................... 60
Bng 3.14: Phn b i tng phng vn theo trnh hc vn .................. 61
Bng 3.15: T l i tng hiu bit v nguy c ly bnh. ........................... 61
Bng 3.16: T l i tng bit tn cc bnh ly t gia cm sang ngi ..... 62
Bng 3.17: T l i tng bit cch phng bnh t gia cm ly sang ngi .. 63
Bng 3.18: T l i tng c kin thc x l khi gia cm mc cm ................. 64
Bng 3.19: T l i tng bit x l chung/tri khi gia cm mc cm ..... 65
Bng 3.20: T l i tng nghin cu bit cch kh trng, tiu c
chung/tri nui gia cm ............................................................. 66
Bng 3.21: T l i tng yu cu tim phng cm cho gia cm ............... 67
Bng 3.22: T l cc loi trang b phng h c nhn c s dng ............. 68
Bng 3.23: Tnh trng dinh dng (ch s khi c th) ................................ 69
Bng 3.24: T l cc bnh mc phi ca cc i tng nghin cu qua khm
lm sng ....................................................................................... 70
Bng 3.25: T l cc bnh mc phi ca cc i tng nghin cu v cc
thnh vin khc cng la tui ..................................................... 71
Bng 3.26: Tnh trng v sinh chung/tri nui gia cm sau can thip ti cc
h chn nui gia cm ................................................................... 72
Bng 3.27: Tnh trng mi trng xung quanh chung tri nui gia cm ca
cc h gia nh ............................................................................. 73
Bng 3.28: Tnh trng ni cha nc thi chn nui gia cm ca cc h gia
nh .............................................................................................. 75
Bng 3.29: T l i tng chn nui gia cm bit c th ly bnh t gia
cm sang ngi............................................................................ 77
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Bng 3.30: T l i tng chn nui gia cm bit cc loi bnh ly sang
ngi ............................................................................................ 78
Bng 3.31: Kin thc ca i tng nghin cu bit x l n gia cm khi
gia cm mc cm ......................................................................... 79
Bng 3.32: Thc hnh x l chung tri khi gia cm b cm ....................... 81
Bng 3.33: Tiu c chung tri nui gia cm .............................................. 82
Bng 3.34: S dng trang b phng h c nhn ............................................. 83
Bng 3.35: Loi phng h c nhn s dng .................................................. 83
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DANH MC BIU
Biu 3.1: Phn b cc thnh vin h gia nh theo gii tnh .................... 50
Biu 3.2: Phn b i tng phng vn theo gii tnh ............................ 60
Biu 3.3: i tng nghin cu thc hin tim phng cho gia cm ....... 67
Biu 3.4: S dng trang b phng h c nhn .......................................... 68
Biu 3.5: Mt s bnh mc phi ca cc i tng nghin cu .............. 70
Biu 3.6: Tnh trng mi trng v sinh xung quanh sau can thip ........ 74
Biu 3.7: Tnh trng ni cha nc thi chn nui gia cm ln iu tra sau .. 75
Biu 3.8: Kin thc ca i tng bit x l n gia cm khi mc cm
ti ln iu tra sau ..................................................................... 80
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DANH MC HNH
Hnh 1.1: Hnh nh chung tri chn nui gia cm ti h gia nh .............. 10
Hnh 1.2: Hnh nh tn thng ng h hp do nhim H1N1 v H5N1 ....... 14
Hnh 1.3: Hnh nh m v vt lot trn da do m t ................................... 16
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T VN
Vit Nam l Quc gia gn lin vi nn kinh t nng nghip. Trong s
pht trin chung ca nn kinh t nng nghip, pht trin ngnh chn nui l
tt yu, trong c ngh chn nui gia cm, thu ht ng o ngi lao ng
nhm m bo cung cp nhu cu v thc phm ca ngi dn cng nh xut
khu ra cng ng quc t. Qu trnh hnh thnh v pht trin ngh chn nui
gia cm chc chn s tc ng khng tt n mi trng sng cng nh nh
hng n sc khe ca con ngi.
Trn th gii c nhng nghin cu v iu kin mi trng lm vic,
tnh hnh sc kho ca ngi lao ng chn nui gia cm nh nghin cu ca
W. Lenhart (1998), Eduard W v cng s (2000) [65], nghin cu ca Brhel
(2003) [63] v ch ra mt s tc ng ca mi trng chn nui gia cm
n i sng v sc khe ca con ngi.
trong nc, cc nghin cu v mi trng, iu kin lm vic v sc kho
ca ngi lao ng trong lnh vc chn nui gia cm cn cha c nhiu v cha
ton din, c bit nghin cu v iu kin an ton v sinh lao ng chn nui
gia cm cc h chn nui gia nh hu nh cha cp ti. Trong khi , vic
chn nui gia cm nh l ti cc h gia nh nc ta chim t l kh cao
(chim ti 60% tng s lng gia cm trn ton quc) so vi chn nui cng
nghip tp trung (nui cng nghip 15%, bn cng nghip 25%) [40]. Cc h
chn nui gia cm hu nh cha p dng cc bin php an ton sinh hc trong
chn nui, cc kin thc v cng tc v sinh phng bnh, m bo an ton v
sinh lao ng cn hn ch, kt hp vi nhn thc ca ngi chn nui v sc
kho ngh nghip cha c y , nn kh nng tim n pht sinh nhiu bnh
tt mang tnh ngh nghip do tip xc v truyn nhim thng qua vt nui l
khng th trnh c.
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c bit ti nng thn Vit nam ngh chn nui gia cm mang tnh
truyn thng, gia cm l nhng vt nui rt gn gi vi con ngi, ng thi
l nhng vt ch mang trng c th trc tip hay gin tip ly lan sang ngi.
Nhng nm gn y t l nhim cc bnh c ngun gc t gia cm sang
ngi v cng ng ang l gnh nng thc s nh chng cm H5N1 (xut
hin nm 2003) v mi y (2013) l chng cm A/H7N9 v ang xut
hin v lu hnh gy ra gnh nng bnh tt ti Trung quc v i loan; Cho
n nay mc d bnh dch v ang c khng ch, nhng vn cn nguy
c ti pht ti nhiu a phng [7].
. gp phn gim bt nguy c tc hi ngh nghip, bo v v nng
cao sc khe i vi ngi lao ng chn nui gia cm, vic nghin cu v
mi trng, iu kin lm vic ti cc chung/ tri, tin hnh khm, kim tra
sc kho v pht hin bnh tt cho ngi lao ng ti cc h gia nh chn
nui gia cm l cn thit, v vy chng ti tin hnh ti: Nghin cu thc
trng mi trng, sc khe ca ngi chn nui gia cm v gii php
can thip ti huyn Ph xuyn, H ni vi cc mc tiu sau:
1. M t thc trng mi trng lm vic, sc kho, kin thc, thc
hnh phng bnh ca ngi chn nui gia cm ti huyn Ph
Xuyn nm 2010.
2. nh gi hiu qu ca gii php can thip nng cao kin thc,
thc hnh phng bnh ly lan t gia cm ca ngi chn nui
gia cm.
T xut mt s bin php nhm ci thin iu kin lao ng, gio
dc nng cao hiu bit v thc hnh v phng chng bnh tt, bo v sc
kho cho ngi lao ng chn nui, gim nguy c ly lan bnh tt t gia cm
sang ngi lao ng v cng ng dn c.
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Chng 1
TNG QUAN
1.1. Thc trng mi trng chn nui gia cm v sc khe ca ngi lao
ng chn nui gia cm
1.1.1. Thc trng iu kin - mi trng chn nui gia cm
Nng nghip c vai tr quan trng trong nn kinh t Vit Nam, chim
t l ln trn 70% tng s lc lng lao ng trn ton quc [5] l mt trong
nhng ngnh kinh t ch o c ngh chn nui v ngh trng trt l chnh,
ngi lao ng phi tip xc trc tip v gin tip vi nhiu yu t c hi c
trong mi trng lao ng, cng nh sn phm ca ngnh to ra. Ngh chn
nui l ngh c th thuc ngnh nng nghip trong c chn nui gia sc,
chn nui gia cm v nui trng thu sn m ring chn nui gia cm l mt
ngh truyn thng ca ngi nng dn, t lu ngh ny gip cho vic m
bo an ninh thc phm trong i sng hng ngy v ngy nay n c vai tr rt
quan trng trong vic gp phn vo cng cuc thc hin chnh sch ca ng
v Nh nc ta trong qu trnh xy dng v pht trin nng thn mi l:
Hin i ha nng nghip, nng dn v nng thn.
Trong thi gian qua ngnh chn nui ca nc ta pht trin rt nhanh,
tc tng trng t 8,9% v nh vy mi ph hp vi tc t tng trng
dn s v p ng c nhu cu thc phm ca ngi dn. C n 80% s h
nng dn chn nui gia cm, nhng ch c 15% s gia cm nui theo phng
php cng nghip, 20% s gia cm chn nui theo phng php bn cng
nghip; trong khi c n 65% s gia cm nui theo phng php truyn
thng (nui theo kiu gia nh nh l v coi vt nui rt gn gi vi con
ngi). Theo Nguyn Khoa L th vic chn nui nh l h gia nh t 20
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30 con/ h hin nay l ch yu [11], vic nui th rng khng kim sot c
v phn ln cc a phng ngi dn ng nhn cho rng ch xut hin dch
cm gia cm nhng ni nui nht tp trung theo kiu trang tri v s dng
thc n chn nui cng nghip, cn vi cc loi gia cm chn nui kiu
truyn thng (th rng) th khng b bnh dch v t nh hng ti sc khe
ca con ngi [16]. Tuy nhin nhng nm gn y cng vi s pht trin
chung ca x hi, cc ngnh khoa hc trong c ngnh khoa hc y hc pht
trin mnh nn rt quan tm n mi trng chn nui gia cm cng nh
cc bnh tt do gia cm gy ra v vic chn nui gia cm truyn thng l
phng thc chn nui t pht mang tnh t cp, t tc, nh k nh, chung
k nh do m kh kim sot c dch bnh trong n gia cm v gy nh
hng n sc kho ca con ngi [45]. Tc tng trng v s lng gia
cm tng rt nhanh t 218 triu con (nm 2001) tng ln 254 triu con (nm
2003) cho n nm 2009 tng n gia cm l 266 triu con [11], cung cp cho
x hi khong 350 ngn tn tht v khong 3.939 triu qu trng [45]; cc
cht thi t cc chung tri trong c cht thi rn t gia cm nh lng,
phn, rc n chung, cc sn phm tha t thc n, thm ch ngay c xc
cht ca cc loi gia cm l rt ln (khong 16,5 tn/nm) v hu nh thi ra
mi trng mt cch t nhin cha h c x l [14].
Cng vi s pht trin tch cc ca ngnh chn nui ni chung, tng
trng mnh v s lng, chng loi v qui m ca chn nui n gia cm
ni ring, th cc nguy c khng mong mun nh nhim mi trng do cc
cht thi t ngun vt nui cng tng theo chiu thun v nh vy kh trnh
khi c mt s bnh hoc nhng tc hi v sc khe do mi trng chn
nui gia cm gy ra, ngoi ra c mt s bnh dch cng tng theo hoc xut
hin mi thm ch c nhng bin i khn lng, nht l dch cm gia cm.
c bit k t nm 2003 khi ti Vit nam chng ta c dch cm gia cm (cm
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A/H5N1) xut hin, lu hnh v ly truyn sang ngi cho n nay th cc a
phng c dch bnh v phi tiu hu nhiu nht l: H Ty c (nay l H
ni); TP. H Ch Minh; ng Nai; Long An v An Giang [9].
Chn nui gia cm l mt ngh rt quan trng c bit l ti mt t
nc c nn kinh t Nng nghip l chnh, nhng nhng in kin tt nht
nh v thit k kin trc chung/ tri, x l cht thi l sn phm t cng vic
chn nui v c bit l c mt s bnh ly t gia cm sang cho con ngi
gn nh cha hoc mi c quan tm rt t. Chnh v vy m sc khe ca
ngi chn nui gia cm ni ring v sc khe ca ngi dn trong cng
ng ni chung l ang b e da nghim trng.
1.1.2. Thc trng v sc kho ca ngi lao ng chn nui gia cm
Trong mi trng lao ng sn xut ca ngnh nng nghip ni chung
c nhiu yu t c hi nh hng n sc khe con ngi. Ngi nng dn
phi lao ng trong iu kin mi trng rt khc nghit k c cc ngnh
ngh trng trt, nui trng thu hi sn, trng rng v ngh chn nui gia sc,
gia cm. Th nhng vn chm sc sc khe cho nng dn, nht l lao ng
n mt s ni vn cha c quan tm ng mc.
Nguy c e do sc kho cho ngi nng dn l rt ln vi lc lng
lao ng chim hn 70% v t l phn nhiu l n gii. Ngh chn nui gia
cm m phn ln l chn nui theo h gia nh nh l, hng ngy phi tip
xc vi cc sn phm ca ng vt nui nh cc cht kh c hi trc tip t
ng vt hay l sn phm do s phn hy ca cc cht thi; hoc cc cht bi
c t cc ht bi sng ha ca da, lng, phn, rc thi t cht n chung,
cc d lng t thc n, t mt s thuc khng sinh hoc thuc kch thch
tng trng; iu ng lu na l mi trng chn nui gia cm c rt nhiu
vi khun, vi rt v ht vi nm c th gy bnh cho con ngi [17].
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6
Nhiu gii php t ra pht huy hiu qu nh ngn chn dch bnh ly
lan, k c trong thi im mt s a phng khc ang c dch bnh trn
gia sc, gia cm. bin php c th nh quy hoch xy dng khu chn nui tp
trung ngoi thnh, h tr di di, nghim cm chn nui trong ni thnh, quy
hoch xy dng cc c s git m tp trung, bc u pht huy tc dng,
bo m v sinh an ton thc phm, ngn nga ly lan dch bnh.
Nhn chung l nhng ngi chn nui gia cm cha c quan tm n
vic chm sc y t v bo v sc khe mt cch c cht lng, cha c nhng
nghin cu chuyn su v sc khe ca nhng ngi chn nui gia cm ni
chung, nu c cng mi ch dng li ti cc nghin cu v sc khe ca
nhng ngi chn nui ti cc trang tri ln mang tnh cht cng nghip, cn
i vi ngi nng dn chn nui gia cm nh l th cn thit thi hu nh
cha c nhng nghin cu cp n. Chnh v vy m cha c cc c nhn
hay cc t chc nh gi cho ng v tnh hnh sc khe ca ngi chn nui
gia cm v do cng cha c cc chnh sch hay cc bin php phng bnh
cng nh cng tc bo v v nng cao sc khe cho ngi chn nui gia cm
mt cch ch ng, tch cc [6].
1.1.3. Thc trng cng tc bo v mi trng trong ngnh Nng nghip
Trong nhiu hi ngh tho lun v tng kt v cng tc chn nui, cng
tc bo v mi trng ca B Nng nghip v Pht trin Nng thn cng nh
ca t chc Nng Lng Th gii c kt lun v vn mi trng v
cng tc bo v mi trng hin nay l ang bc xc [11] do l:
Pht trin th y khng theo qui hoch; Cc trang tri chn nui tp
trung theo hng cng nghip cn rt t, phn ln cc trang tri ny khng c
h thng x l cht thi; thc trng nhim trong cc khu chn nui, git m,
s ch sn phm ng vt, sn xut thc n chn nui; kinh doanh sn xut
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7
thuc th y/ kho nghim thuc th y; dch bnh gia cm; c s chn on,
xt nghim bnh gia cm; nhim u ngun do cc trang tri qui m ln;
nhim t nhng h chn lp gia cm sau dch bnh [6].
Lng rc thi mi thu gom c ti cc thnh ph m cng ch t
c 45-55% [28]; ti khu vc nng thn gn nh cha thu gom c, m
gy nh hng ln ti v sinh mi trng, cc cht tiu biu trong l nc
thi t cc chung tri chn nui (2 trong s 1500 tc nhn) gy nhim
khng kh, t v ngun nc sinh hot m iu ng quan tm l ngun
nc mt v ngun nc ngm nng, y l ngun nc sinh hot chnh ca
ngi dn sinh sng ti cc vng nng thn [37].
1.2. C s l thuyt lin quan n mi trng v nhng nh hng ca
chng ti sc khe ca ngi chn nui gia cm
1.2.1. H chn nui gia cm
Theo quan nim ca Cc Th y: H gia nh (HG) chn nui gia cm
nh l (bao gm c g, ngan, vt, ng ng) c qui m t 50 n di 200 con
[25] [27]. Gia tri: qui m n gia cm t 200 n di 2.000 con. Trang tri:
qui m n gia cm trn 2.000 con.
Theo d n ca chng trnh Vit nam - Canada hin nay nh ngha tu
thuc vo iu kin kinh t - x hi - mi trng - ti chnh m chia thnh: h
chn nui gia cm nh l l nhng h nui vi qui m nh vi s lng di
200 con. H chn nui vi qui m va l t 200 n 1000 con. Trang tri: qui
m trn 1000 con v phi c ng k chn nui vi trm th y cp huyn.
1.2.2. Mi trng
Mi trng bao gm cc yu t t nhin v vt cht nhn to bao quanh
con ngi nh hng n i sng, sn xut, s tn ti, pht trin ca con
ngi v sinh vt [34][44].
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Nh vy n bao hm 3 nhm thnh t to thnh mt h thng cu trc
mi trng [4]: cc thnh t sinh thi t nhin bao gm: t trng trt, lnh
th, nc, khng kh, ng thc vt, cc h sinh thi, cc trng vt l (nhit,
in, t, phng x); cc thnh t x hi nhn vn gm: dn s v ng lc dn
c, tiu dng, x thi, ngho i, gii, dn tc, tp qun vn ho, li sng,
thi quen v sinh; cc thnh t v lut, chnh sch, hng c, l lng; t
chc cng ng x hi; cc iu kin tc ng: cc chng trnh v d n
pht trin kinh t, hot ng qun s, chin tranh; cc hot ng kinh t
(nng, lm, ng nghip, cng nghip, du lch, xy dng, th ho); cng
ngh, k thut, qun l.
1.2.2.1. Mi trng trong chn nui
Thc trng nhim mi trng hin nay ca Vit Nam l ng bo ng
trong c nhim trn cc lnh vc: t, nc v khng kh do cc iu
kin tc ng thuc nhiu ngnh ngh khc nhau.
L mt quc gia c nn nng nghip lu i. Ngun thu nhp chnh ca
ngi lao ng cc vng nng thn ch yu vn da vo trng trt v chn
nui. Trong , chn nui cc loi gia sc, gia cm nh: ln, g, vt c
hnh thnh t kh sm. Trc y, quy m cn manh mn v nh l, ngun
thc n chn nui ch yu l tn dng ngun ph phm nng nghip, cc tiu
ch v con ging, cht lng tht hay nhim mi trng hu nh cha c
x hi quan tm n. Ngh chn nui gia cm ch c vng nng thn mang
tnh truyn thng c tnh cht gia nh, t pht; ch yu t cung t cp v t
tnh ton hiu qu hay li ch v kinh t. Cc cht thi do chn nui trng ch
ch yu vo qu trnh lm sch t nhin ca mi trng ch khng c cc
bin php h tr ca con ngi [36].
Ngy nay, vi s pht trin mnh m ca khoa hc k thut, i sng
con ngi ngy cng c nng cao, nhiu m hnh chn nui gia cm nh
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quy m gia tri, trang tri hnh thnh. S lng con ging, sn lng tht
v trng ngy cng tng. nhim mi trng ti cc c s chn nui ngy
nhiu v a dng. Cng tc kim sot v sinh th y v mi trng trong
ngnh chn nui gia cm vn cn rt hn ch [41].
Ngh git m v ch bin nng lm sn thc phm c nhu cu v nc
sch l rt ln v gy nhim hu c nghim trng. Hu ht nc thi u c
hm lng BOD (nhu cu oxy sinh ha) vt tiu chun cho php 12,8-140
ln, COD (nhu cu oxy ha hc) vt t 9,7-87 ln. Nu nh khng c qui
hoch li mt cch ng b v khng c cc bin php x l khoa hc, c
bit l ngun nc th n tr thnh nhng nguyn nhn gy ra nhiu bnh cho
cng ng: bnh ph khoa chim 13-38%; tiu ho chim 8-30%; vim da
4,5-23%; h hp 6-18%; au mt 9-15% [29].
Thc trng cng tc bo v mi trng nng nghip v nng thn
Nhng vn ang bc xc [3]: ring mi trng trong chn nui do pht
trin th y khng theo qui hoch. Phn ln trang tri chn nui khng c h
thng x l cht thi. Thc trng nhim trong cc khu chn nui, git m,
s ch sn phm ng vt, sn xut thc n chn nui. Kinh doanh sn xut
thuc th y/ kho nghim thuc th y; dch bnh gia cm, c s chn on,
xt nghim bnh gia cm. nhim u ngun do cc trang tri qui m ln.
nhim t nhng h chn lp gia cm sau dch bnh [24].
Lng rc thi mi thu gom c ti cc thnh ph m cng ch t
c 45-55% [28]; ti khu vc nng thn gn nh cha thu gom c, m
gy nh hng ln ti v sinh mi trng, cc cht tiu biu trong l nc
thi t cc chung tri chn nui (2 trong s 1500 tc nhn) gy nhim
ngun nc sinh hot [37].
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10
1.2.2.2. Mi trng trong chn nui gia cm
Lnh vc chn nui trong nng nghip v pht trin nng thn l rt
rng, to rt nhiu sn phm, cung cp cho x hi mt khi lng khng l v
thc phm. Nhng sn phm chnh trong ngnh chn nui bao gm chn nui
gia sc nh ln, tru, b; v c bit l chn nui gia cm nh ng ng, vt,
ngan, g l lnh vc m rt quen thuc vi mi ngi dn v mi vng min
ca nc ta. Bn cnh nhng mt tch cc v khng th thiu trong sn xut
nng nghip th qu trnh chn nui cng to ra khng t nhng sn phm gy
nhim mi trng ( nhim khng kh, t v ngun nc sinh hot) v to
ra nhng bin i kh hu cng nh nhiu tc hi trc tip hay gin tip n
sc kho ca con ngi.
Cc hot ng gy nhim do chn nui tip tc din ra nhiu ni trn c
nc. Tnh trng chn nui th rng, chn th trn t dc, u ngun nc cn
kh ph bin gp phn lm tng din tch t xi mn, suy gim cht lng
t, nc, gim thiu kh nng sn xut nng nghip trn vng rng ln.
Hnh 1.1: Hnh nh chung tri chn nui gia cm ti h gia nh
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Nguyn nhn c FAO nhn nh l do nhu cu v thc phm ca con
ngi ang ngy mt tng cao v a dng trong khi vic quy hoch chn nui
li ty tin, vic x l cht thi chn nui khng ng b v yu km. Ti
Vit Nam, hin trng nhim do chn nui gy ra ang ngy mt mc bo
ng. X Trc Thi (Nam nh) c 91,13% h nui. Kt qu m c quan
chc nng thu c l mc khi c NH3, H2S cao hn mc cho php 4,7 ln,
mc nhim khun khng kh trong chung nui trung bnh l 18.675 vi sinh
vt (cao hn tiu chun ca Nga 12 ln), nc thi nhim E.Coli v 25% s
mu nhim trng giun vi mt 4.025 trng/500ml nc thi. Hm lng
COD l 3.916 mg/l trong khi TCVN 5945-2005 quy nh mc COD trong
nc thi cng nghip ni chung l di 80mg/lt.
Cc hp cht c cha arsenic c tc dng kch thch tng trng cho g
tht v g li rt hiu qu. Tuy nhin, cc hp cht ny c th b phn gii
sinh ra cht arsen rt c hi cho mi trng v l yu t gy nn bnh ung
th. Quy trnh sn xut tht sch phi bt u t trang tri nhng vic xc nh
tnh cht t, nc v cc yu t x hi - t nhin khc nh trnh dn tr, tp
qun sinh hot, dc, a hnh... thm ch n cc tiu ch xy dng trang tri,
quy hoch tng loi trang tri cn cha c c quan chc nng cc cp ban
hnh ng b v hiu qu p ng thc t cn thp. Quy hoch chn nui cn
lng tng, vic x l hu qu ca cc trang tri trc y nm trong khu dn
c nh th no, hng dn chn nui nh l an ton, xc nh vng nguyn liu
sn xut thc n chn nui, bi chn th cn ht sc nan gii.
1.2.3. Yu t tc hi ngh nghip trong chn nui gia cm v nh hng
ca chng ti sc khe ngi lao ng
Bi: trong mi trng chn nui gia cm n pht sinh t cc cht sng
nh lng, mng; phn gia cm v nhng d lng t cc loi thc n chn
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nui thm ch c nhng ho cht kh trng, kh mi hi, thuc iu tr cho
n gia cm b bnh, nhng bo t nm, bi t cc cht n chung, chng
c th gy d ng, kch thch trc tip da v nim mc mt, c bit l nim
mc ng h hp hoc l ngun mang cc nguyn nhn gy bnh nh nm,
cc loi vi trng hoc vi rt. c bit c th gp hi chng bi hu c c
hi (Organic Dust Toxic Syndrome = ODTS) [92], l hi chng ging nh
cm c kh nng gy bnh nghim trng bc u c m t nhng
ngi chn nui, cng nhn nm, cc nh nhn ging chim v nhng ngi
khc ngh nghip c tip xc vi iu kin bi bm [62].
Triu chng: Cc triu chng xut hin t 4 n 12 gi sau khi tip xc
vi bi hu c v thng ko di 1 5 ngy. Cc triu chng ph bin tng
qut bao gm st trn 38oC, n lnh, au c v mt mi. Cc triu chng ti
c quan h hp thng gp nht l kh th v ho khan, th kh kh t gp
hn. Nhc u, vim mi, vim kt mc, vim gic mc v kch ng da cng
c th gp [94].
Nguyn nhn: ng h hp tip xc vi bi hu c c nng cao
c to ra bi mt s h n hp cc cht thi c hi: chng c th l cc
mnh v ca cc loi ht thc vt, mt s thc n t ng vt, vt cn ca cn
trng, vi khun, bo t nm, nm mc hoc d lng ha cht, tng ht kch
c t 0,1 n 50 micron [94]. Mt biu hin ph bin l sau khi tip xc vi
cc ht mc, c kh hoc dm g , ngi nng dn v cng nhn chn nui gia
cm nhng ngh ph bin nht thng xut hin cc triu chng trn. Nhng
ngi lm vic vi gia cm, ng cc v nm cng thng xuyn bo co cc
triu chng v hi chng nhim c ny [94].
Kh NH3 : L sn phm to ra t nc tiu v m d tha trong phn
ca sc vt, gia cm. Khi nng NH3 t 25 phn triu s xut hin cay mt,
http://translate.googleusercontent.com/translate_c?depth=1&hl=vi&prev=/search%3Fq%3Dorganic%2Bdust%2Btoxic%2Bsyndrome%2B%28odts%29%26hl%3Dvi%26biw%3D1272%26bih%3D624%26prmd%3Dimvns&rurl=translate.google.com.vn&sl=en&u=http://en.wikipedia.org/wiki/Flu-like&usg=ALkJrhg4YrxEg2bnZVNFSm-GQz9RXFxW1ghttp://translate.googleusercontent.com/translate_c?depth=1&hl=vi&prev=/search%3Fq%3Dorganic%2Bdust%2Btoxic%2Bsyndrome%2B%28odts%29%26hl%3Dvi%26biw%3D1272%26bih%3D624%26prmd%3Dimvns&rurl=translate.google.com.vn&sl=en&u=http://en.wikipedia.org/wiki/Flu-like&usg=ALkJrhg4YrxEg2bnZVNFSm-GQz9RXFxW1g
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ho, gim kh nng chng bnh tt; Nng NH3 t 50 phn triu s xut
hin mi hi kh chu, gim kh nng tp trung v xut hin cc triu chng
v thn kinh nh mt mi, chng mt v nhc u [43].
Kh CO2 : Trong chn nui kh CO2 l sn phm ca s phn hy t phn
v hi th ca gia sc, gia cm. Khi nng CO2 trong mi trng khng kh
ln ti 60.000ppm ko di trn 30 pht sc khe con ngi bt u b nh
hng; khi nng t trn 200.000ppm sc vt (ln) khng chu ni trn 1
gi; vi bu kh quyn n nh hng quan trng n hiu ng nh knh, lm
tng hiu ng v lm tri t nng ln [43].
Kh H2S: Sn phm phn hy t phn ca ng vt; Khi nng H2S
trong khng kh l 1 ppm con ngi c th nhn bit c; khi nng
H2S ln ti 150 ppm c th gy t vong cho ngi v sc vt [69][99].
Hydrogen sulfide c coi l mt cht c ph rng, c ngha l n c th
u c mt s h thng khc nhau trong c th, mc d h thng thn
kinh b nh hng nht [59][74].
Tip xc vi nng thp hn c th gy kch thch mt, au hng v
ho, bun nn, kh th, v cht dch trong phi. Cc hiu ng ny c cho l
do Hydrogen sulfide (mt cht c qun i Anh s dng trong chin
tranh th gii th nht nm 1916) [80] kt hp vi kim hin din trong cc
m b mt m to thnh sunfua natri, mt cht n da [66]. Nhng triu
chng ny thng mt i trong mt vi tun.
Vi sinh vt: Cc vi khun gy bnh hiu kh v ym kh; cc loi k sinh
trng nht l cc k sinh trng ng rut, xon khun [12]. c bit l vi
rt: vi rt loi B gy cm ngi nhng t l t hn. Loi ny thnh thong c
th gy cm loi hi cu [76][90]. Loi B thay hnh i dng chm hn vi
rt cm loi A [82][100] v do ch c 1 dng huyt thanh [94][95]. Con
http://translate.googleusercontent.com/translate_c?depth=1&hl=vi&prev=/search%3Fq%3DH2S%2Bpoisoning%2Bsyndrome%26hl%3Dvi%26biw%3D1272%26bih%3D624%26prmd%3Dimvns&rurl=translate.google.com.vn&sl=en&u=http://en.wikipedia.org/wiki/Nervous_system&usg=ALkJrhjrUkRh_kmKOh1nq2IP5r7QOY2smQhttp://translate.googleusercontent.com/translate_c?depth=1&hl=vi&prev=/search%3Fq%3DH2S%2Bpoisoning%2Bsyndrome%26hl%3Dvi%26biw%3D1272%26bih%3D624%26prmd%3Dimvns&rurl=translate.google.com.vn&sl=en&u=http://en.wikipedia.org/wiki/Nervous_system&usg=ALkJrhjrUkRh_kmKOh1nq2IP5r7QOY2smQhttp://translate.googleusercontent.com/translate_c?depth=1&hl=vi&prev=/search%3Fq%3DH2S%2Bpoisoning%2Bsyndrome%26hl%3Dvi%26biw%3D1272%26bih%3D624%26prmd%3Dimvns&rurl=translate.google.com.vn&sl=en&u=http://en.wikipedia.org/wiki/Human_eye&usg=ALkJrhhrTRvtj0dWRWMoJPUUBOnztqSaZAhttp://translate.googleusercontent.com/translate_c?depth=1&hl=vi&prev=/search%3Fq%3DH2S%2Bpoisoning%2Bsyndrome%26hl%3Dvi%26biw%3D1272%26bih%3D624%26prmd%3Dimvns&rurl=translate.google.com.vn&sl=en&u=http://en.wikipedia.org/wiki/Cough&usg=ALkJrhj5SUUHVouFjsXbH8R1y5W0hq0-vghttp://translate.googleusercontent.com/translate_c?depth=1&hl=vi&prev=/search%3Fq%3DH2S%2Bpoisoning%2Bsyndrome%26hl%3Dvi%26biw%3D1272%26bih%3D624%26prmd%3Dimvns&rurl=translate.google.com.vn&sl=en&u=http://en.wikipedia.org/wiki/Lung&usg=ALkJrhiR3-nRulMPC2e53_77-UFTIeJ3oghttp://translate.googleusercontent.com/translate_c?depth=1&hl=vi&prev=/search%3Fq%3DH2S%2Bpoisoning%2Bsyndrome%26hl%3Dvi%26biw%3D1272%26bih%3D624%26prmd%3Dimvns&rurl=translate.google.com.vn&sl=en&u=http://en.wikipedia.org/wiki/Alkali&usg=ALkJrhjuaGReT6mnEr3mkrU8KdvuhokMpwhttp://translate.googleusercontent.com/translate_c?depth=1&hl=vi&prev=/search%3Fq%3DH2S%2Bpoisoning%2Bsyndrome%26hl%3Dvi%26biw%3D1272%26bih%3D624%26prmd%3Dimvns&rurl=translate.google.com.vn&sl=en&u=http://en.wikipedia.org/wiki/Sodium_sulfide&usg=ALkJrhiQUgUhw39jshhCnH5iJp0MscqU-ghttp://translate.googleusercontent.com/translate_c?depth=1&hl=vi&prev=/search%3Fq%3DH2S%2Bpoisoning%2Bsyndrome%26hl%3Dvi%26biw%3D1272%26bih%3D624%26prmd%3Dimvns&rurl=translate.google.com.vn&sl=en&u=http://en.wikipedia.org/wiki/Corrosive_substance&usg=ALkJrhhARRxx1h_TiI69A-UOf2oF_JqgvQhttp://vi.wikipedia.org/wiki/H%E1%BA%A3i_c%E1%BA%A9uhttp://vi.wikipedia.org/wiki/C%C3%BAm#cite_note-hay-12#cite_note-hay-12http://vi.wikipedia.org/wiki/C%C3%BAm#cite_note-hay-12#cite_note-hay-12
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ngi thng gp vi rt cm loi B t b v thng c min nhim nhng
khng c c lu v loi ny thng cng hay i dng [73]. Nhng v bin
i chm v c lc thp nn vi rt cm loi B khng gy nhng trn dch ln
nh vi rt cm loi A [61] [70] [89].
Triu chng nhim vi rt cm gia cm ngi
Hnh 1.2: Hnh nh tn thng ng h hp do nhim H1N1 v H5N1
i vi con ngi, cm gia cm gy ra cc triu chng tng t nh ca
cc loi cm khc [71][91][101]. l st, ho, au hng, au nhc c bp,
vim mng kt v nhng trng hp nghim trng c th gy vim phi v
suy h hp nng, c th dn n t vong. Mc nghim trng ca bnh ph
thuc phn ln vo th trng sc kho, kh nng min dch, tin s tip xc
vi virus ca ngi b nhim [10][31][96].
Mt s nm cng l tc nhn gy bnh cho con ngi nh nm mng,
nm da, ri nm gy cc bnh l v h hp v tiu ho. n nay c hn
10.000 loi nm c bit n, a s trong chng u c li cho con ngi
nh trong vic sn xut bnh m, pho mt, khng sinh, men [24]. Nhng c
khong 50 loi nm mc c mt trong thc n v nguyn liu lm thc n
(ng cc) gy hi cho vt nui v con ngi v chng sn sinh ra c t,
ngi ta thng gi tn chng l c t nm mc (mycotoxin).
http://vi.wikipedia.org/wiki/T%E1%BA%ADp_tin:H1N1_versus_H5N1_pathology.pnghttp://vi.wikipedia.org/wiki/T%E1%BA%ADp_tin:H1N1_versus_H5N1_pathology.pnghttp://vi.wikipedia.org/w/index.php?title=Vi%C3%AAm_m%C3%A0ng_k%E1%BA%BFt&action=edit&redlink=1
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Bng 1.1: Cc c t nm mc c pht hin
Nm/ mc c t nm Thng c trong
Aspergillus flavus & A.
parasiticus
Aflatoxin Ng cc v cc ht c du
Aspergillus v Penicilium Ochratoxin A La mch, yn mch, la m, ng
Furasium Zearalenone Ng, u nnh
Furasium DON
(vomitoxin)
Ng, la m
Furasium T-2 Ng cc
Furasium Fumonisin B1 Ng, la m
Vic tng cng kin thc, hiu bit v nm mc, c t nm v nhng tc
hi ca chng c nhng bin php hu hiu trong vic phng chng bnh tt,
bo v v nng cao sc khe cho vt nui v con ngi l cn thit [46].
1.2.4. Cc bnh gy ra do tip xc trc tip vi mi trng chn nui gia cm
+ Bnh do b kch thch da, nim mc hay d ng: bnh v mt; bnh v
mi hng; bnh v h hp, vim da, vim mng (nm mng).
+ Bnh do m t: bnh st m (scrub typhus) l bnh do loi m
Trombicula b nhim mm bnh Rickettsia tsutsugamushi, cn gi l Rickettsia
orientalis ly truyn xm nhp qua vt m t mu v gy bnh cho ngi.
M c tp tnh chn lc vt ch k sinh, n a thch k sinh loi ng
vt gm nhm, ng vt n cn trng. M cng c th k sinh g, chim, di
v cc loi b st. u trng m Leptotrombidium deliense c vai tr truyn
bnh Vit Nam, thch k sinh trn loi chut nh Rattus flavipectus v mt
s loi chut khc sng gn ngi.
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M g Mt vt lot do m t
Hnh 1.3: Hnh nh m v vt lot trn da do m t
u trng m cng c tp tnh chn lc v tr k sinh. chut, m
thng k sinh trong l tai, quanh mt, quanh v. ngi, m thng k
sinh nch, rn, bn... Ni chung, u trng m c xu hng a thch k sinh
nhng ch da mm, m ca vt ch. N cng a vt th mu en, ni c
nh sng v kh carbonic CO2 [55].
- St m c mt hu ht 24 tnh pha Bc (cha k cc tnh pha Nam).
- Chim 38,51% s bnh nhn st nhp vin, khng r cn nguyn.
- Khong 31,8% bnh nhn st m khng r vt lot c trng.
Ba im trn gi st m cn c tng cng gim st v phng
chng [48].
+ Bnh tm thn kinh do mi hi thi lu ngy nh au u, kh chu,
gim tr nh. Bnh khc do lao ng (ngh nghip): c th pht sinh trong qu
trnh chn nui, git m, lm nh hng n sc kho ca con ngi.
1.2.5. Bnh do vi sinh vt
Vi sinh vt: vi khun dao ng 500/m3 trong iu kin thi tit nng,
10.000/m3 trong iu kin thi tit lnh; phn ln l t cu trong phn (theo
Stanley-1966) lng E.Coli l rt t. Theo qui nh ca EU tiu chun vi sinh
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17
ni lm vic v sn xut thc phm (Romanova.1991). Tng s vi sinh vt
cho php t 1.250 3.125/m3 khng kh, tng s nm mc < 130/m
3.
Ngoi ra cn rt nhiu cc loi vi rt gy bnh ng quan tm v ni
ln hng u l cc loi vi rt cm: siu vi trng thuc h Orthomyxoviridae
c Richard Schope khm ph trong loi heo nm 1931 [98]. Nm 1933,
nhm nghin cu y t Anh Quc do Patrick Laidlaw hng dn tm ra vi rt
cm trong con ngi [93]. Nhng n 1935 qua cng trnh khoa hc ca
Wendell Stanley mi nhn thc c th trng "v bo" ca vi rt cm.
Vi nm sau, Frank Macfarlane Burnet khm ph ra rng vi rt mt sc
gy bnh nu c cy trong trng g [78]. Nm 1944 nhm nghin cu ca
Thomas Francis, Jr. ti i hc Michigan c qun i Hoa K bo tr tm
vc-xin chng cm u tin [68]. Qun i Hoa K b rt nhiu cng sc vo
vic tm vc-xin cm (sau th chin II, trong vi thng nm 1918, hng ngn
lnh Hoa K b cm v t vong) [91].
Sau trn dch cm ti Hng Kng nm 1968, nhng trn dch khc,
nh ti New Jersey (1976), Nga (1977), Hng Kng (1997) u gy t thit
hi cho con ngi. C l do con ngi ngy cng c kh nng min nhim
tt hn [84]. Phn loi vi rt cm: vi rt cm c ba loi: A, B v C. Loi A
v C gy cm nhiu ng vt, loi B ch nhim ring loi ngi [94]. Vi
rt loi A gy cm trm trng ngi, c chia dng theo khng th ca
huyt thanh (serotype) nh sau [94]. Bao gm cc nhm: H1N1 "cm ty
Ban Nha"; H2N2 "cm chu"; H3N2 "cm Hng Kng"; H5N1 cm "gia
cm" trong hai nm 2006 - 2007; H7N7 cm c kh nng l, gy cm gia
cm v ngi [75] H1N2 gy cm ngi v heo; H9N2, H7N2, H7N3,
H10N7 [21]. Dch cm do vi rt nhm A c nhiu bin th gy ra cho con
ngi rt a dng, cp tnh v nguy him kh lng, thng gy t vong.
http://vi.wikipedia.org/w/index.php?title=Richard_Schope&action=edit&redlink=1http://vi.wikipedia.org/wiki/Heohttp://vi.wikipedia.org/wiki/1931http://vi.wikipedia.org/wiki/1933http://vi.wikipedia.org/wiki/Anh_Qu%E1%BB%91chttp://vi.wikipedia.org/w/index.php?title=Patrick_Laidlaw&action=edit&redlink=1http://vi.wikipedia.org/wiki/1935http://vi.wikipedia.org/w/index.php?title=Wendell_Stanley&action=edit&redlink=1http://vi.wikipedia.org/w/index.php?title=Frank_Macfarlane_Burnet&action=edit&redlink=1http://vi.wikipedia.org/wiki/1944http://vi.wikipedia.org/w/index.php?title=Thomas_Francis,_Jr.&action=edit&redlink=1http://vi.wikipedia.org/w/index.php?title=%C4%90%E1%BA%A1i_h%E1%BB%8Dc_Michigan&action=edit&redlink=1http://vi.wikipedia.org/wiki/Th%E1%BA%BF_chi%E1%BA%BFn_IIhttp://vi.wikipedia.org/wiki/Hong_Konghttp://vi.wikipedia.org/wiki/1968http://vi.wikipedia.org/wiki/New_Jerseyhttp://vi.wikipedia.org/wiki/1976http://vi.wikipedia.org/wiki/Ngahttp://vi.wikipedia.org/wiki/1977http://vi.wikipedia.org/wiki/Hong_Konghttp://vi.wikipedia.org/wiki/1997http://vi.wikipedia.org/w/index.php?title=H1N1&action=edit&redlink=1http://vi.wikipedia.org/w/index.php?title=H2N2&action=edit&redlink=1http://vi.wikipedia.org/w/index.php?title=H3N2&action=edit&redlink=1http://vi.wikipedia.org/wiki/H5N1http://vi.wikipedia.org/wiki/2006http://vi.wikipedia.org/wiki/2007http://vi.wikipedia.org/w/index.php?title=H7N7&action=edit&redlink=1http://vi.wikipedia.org/w/index.php?title=H1N2&action=edit&redlink=1http://vi.wikipedia.org/wiki/Heohttp://vi.wikipedia.org/w/index.php?title=H9N2&action=edit&redlink=1http://vi.wikipedia.org/w/index.php?title=H7N2&action=edit&redlink=1http://vi.wikipedia.org/w/index.php?title=H7N3&action=edit&redlink=1http://vi.wikipedia.org/w/index.php?title=H10N7&action=edit&redlink=1
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18
c bit l i vi bnh nhn tr em mc cm loi ny biu hin rm r st,
ho, kh th sau tiu chy cp, hn m v t vong [86][87][88].
1.2.6. Bnh ngh nghip v nhng bnh lin quan ti ngh nghip
Nguyn nhn ca bnh ngh nghip l do tc hi thng xuyn v
lu di ca iu kin lao ng khng tt. Ngay t khi c lao ng, bnh
ngh nghip xut hin v gy nh hng ti ngi lao ng.
Hippocrates pht hin ra bnh nhim c ch ngay t khong th k 5
n 4 trc cng nguyn. Pliny the Elder cng ni ti nhng nh hng
ca bi n sc khe con ngi [72][88].
T chc Lao ng Quc t hin nay phn loi bnh ngh nghip
thnh 29 nhm vi hng trm bnh khc nhau. Cc cng nhn c nguy c
mc bnh ngh nghip phi c hng ch bo him nn cc quc gia
cng c nhng quy nh v bnh ngh nghip ring [97]. Vit nam hin nay
mi ch c 28 bnh ngh nghip c hng ch bo him x hi [33].
Ngi chn nui gia cm thng xuyn tip xc hng ngy vi mi
trng nh khng kh, t, nc thi trong c nhiu tc nhn gy bnh nh
nhng ho cht c s dng trong chn nui (trong thc n, v sinh, tiu c
chung tri, cc thuc phng v cha bnh cho gia cm...); cc sn phm cht
thi trc tip hay gin tip t gia cm nh: bi phn, lng, v cc sn phm
sau khi phn hu...; cc bnh ly t gia cm hay do tip xc nh: b t, vim
da, vim nim mc (vim mi hng, vim gic mc), d ng hoc kch thch,
cc bnh l v tm thn kinh do b chu tc ng ca kch thch hoc do mi
hi thi kh chu.
http://vi.wikipedia.org/wiki/Hippocrates
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19
1.3. Nhng nghin cu v nh hng ca iu kin mi trng chn nui
gia cm ti sc khe ngi lao ng
1.3.1. Nhng nghin cu v nh hng ca KMT chn nui gia cm ti
sc khe ngi lao ng trn th gii
Trn th gii, vic nghin cu mi trng, iu kin lm vic v sc
kho ca ngi lao ng chn nui c cc tc gi nc ngoi quan tm t
lu v kh ton din. Lao ng chn nui hng ngy tip xc vi cc yu t
ho hc v bi hu c gy ra cc bnh d ng c quan h hp, lm gim chc
nng thng kh phi, kch thch da, nim mc v mt ngi lao ng. Ngoi
ra, ngi lao ng ngh chn nui cn c th mc mt s bnh ngh nghip
do yu t vi sinh truyn t gia cm nui sang ngi nh bnh st m, nm
phi, dch cm gia cm tc cm A/H5N1 v nhng bin th ca chng.
Ngi chn nui phi tip xc vi cc cht c ho hc l: hi kh
Amoniac (NH3) thi ra trong qu trnh phn hu vi sinh t phn, nc tiu; kh
cacbon dioxyt (CO2) t kh th ra ca vt nui v t qu trnh ln men thu
phn; mt s kh khc nh: CO, H2S, SO2, CH4 v cc kh c thnh phn nit
oxit (N2O) do qu trnh phn hu phn v t chy nguyn liu. Trong s ho
cht c dng kh khun mi trng trong chn nui l Formaldehyde.
Cho n nay, ngi ta cho rng y l cht c nguy c gy ung th cho con
ngi. Da trn cu trc ho hc v mt s nghin cu ch ra cc hi
kh Amoniac v Hydrosulfua, Amoniac v Formaldehyde l nhng cht
ho hc c tc dng cng hng, tng nh hng xu n sc kho ngi
lao ng [37]. V vy, ti liu hng dn ca CIS xut cn phi thay th
cht kh trng khc c thnh phn t c hn ch v kh nng tng nh
hng tc hi (cng hng nh hng Synergistic effects) i vi h h
hp c bit khi tip xc ng thi vi hi kh c hi, bi v yu t ht
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20
thuc k c khi s dng h thng si nng cng l yu t tc hi n sc
kho ngi lao ng. Ngoi ra, lao ng nng nghip trong c lao ng
chn nui cn c mt s c im khng thun li v mt kinh t - x hi.
l iu kin v sinh c ch lm vic v ch thng khng tt, ch
thng gn ch chn nui nn tc hi c n cc thnh vin trong gia
nh, trong c tr em, ngi gi, lao ng khng n nh mang tnh thi
v, trnh giao tip thp.
Theo kt qu nghin cu ca Senkman G.X. (1979), mi trng lao
ng cc chung chn nui gia cm (nui g) b nhim kh nng vi nng
NH3 l 48 - 76mg/m3 (TCVSCP 20mg/m
3), kh H2S 39mg/m
3 (TCVSCP
10mg/m3), kh CO2 t 0,3 n 0,45% (TCVSCP 0,1%), bi ch yu c kch
thc < 5m (micromet) c nng 50 - 280 mg/m3 (TCVSCP 2mg/m
3) khi
v sinh chung tri, v iu kin vi kh hu khng thun li vi nhit -3
n -5oC, m 90-95% th nng vi khun mc khng kh rt bn [93].
Nghin cu ca Steven W.Lenhart (1998) nhn thy, nhng yu t
nguy c nh hng ti sc kho ngi lao ng chn nui gia cm ngy cng
tng. Lao ng nng nghip pht trin, trong c chn nui gia cm cng
ngy cng pht trin. Tng n gia cm, i hi ngi chn nui lm vic
nhiu hn trc (7 ngy trong mt tun). Khi c dch bnh gia cm, lao ng
chn nui l ngi u tin phi tip xc trc tip vi cc gia cm mc bnh.
Khng kh trong nh ca cc h chn nui g c cc hi kh c hi nh
Amoniac (NH3) t rm rc lt chung, kh Hydrosulfua (H2S ) t phn v
nc tiu, cc ht bi hu c v v c l lng trong khng kh c ngun gc
t rm rc lt chung, t lng, t bi thc n. Ngoi ra ngi lao ng cn
thng xuyn b chm t bi gin, rui mu i, b; tip xc vi mi trng c
virus, vi sinh vt c hi, ni c t ca vi khun, nm; tip xc vi cc mi
kh chu nh mi phn v mi cay ca Amoniac ln ln vi nhau [96].
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21
Theo trung tm thng tin v an ton - sc kho ngh nghip quc t
(International Occupational Safety and Health Information Centre CIS) ca
t chc lao ng quc t (ILO), ngi lao ng chn nui gia sc, gia cm do
chu nh hng tc hi ca mi trng bi cao (gm c bi hu c v bi v
c), tip xc vi mt s hi kh c hi v c mc nhim vi sinh cao
pht trin cc bnh vim nhim cp tnh v mn tnh c quan h hp, cc
bnh h min dch nh vim mi hng d ng, hen, vim phi qu mn, b
kch thch nim mc; mc cc bnh cp v mn tnh v da v mt [77].
Kt qu nghin cu v sc kho, bnh tt ngi chn nui gia sc, gia
cm Nga (Senkman G.X., 1979) cho thy, cc bnh h hp (vim ph qun,
hen ph qun, vim phi), bnh ngoi da (vim da v nm da, sn nga); h
thn kinh ngoi bin chim t l cao nht (40 50%); cc tai nn, chn
thng, bnh vim c khp v mt s bnh k sinh trng ly truyn t gia sc
sang ngi, ng thi cc bnh thuc h tiu ho, h tim mch cng gp cao
ngi lao ng nng nghip, trong c lao ng chn nui [96].
Theo Steven W.Lenhart (1998), ngi lao ng chn nui gia cm
(nui g) khng c phng tin bo v c nguy c cao pht trin cc bnh d
ng ng h hp nh vim mi d ng, hen ph qun, vim phi qu mn
hoc vim ph nang d ng, hi chng nhim c bi hu c (ODTS); ng
thi pht trin cc bnh vim h hp cp tnh v mn tnh vi cc triu chng
nh ho, th rt, tit dch nhiu t nim mc, kh th v au ngc. Kt qu o
chc nng h hp cho thy ngi lao ng khng ch mc cc bnh tc
nghn mn tnh nh vim ph qun mn tnh v hen m cn b hi chng
hn ch do vim phi qu mn mn tnh; ngoi ra h cn mc cc triu
chng: kch thch mt, bun nn, au u v st. Ngi chn nui gia cm
mc 6/40 bnh truyn nhim ly t sc vt sang ngi trong c bnh st
v vim phi do vi rt. cc nc c ngnh chn nui gia cm tp trung
pht trin, cng vic ca ngi lao ng thu hoch g (bt g) c nguy c
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22
cao ri lon xng khp vng ct sng v tay, b tn thng xy xc, vim
da tay v i do t th ci bt vi nghn con g trong mt ca v xch 8
15 con g, m i con c trng lng t 1,8 2,3kg [85]. M, theo nghin
cu ca Donham nm 2000, c ti 70 % cng nhn chn nui mc vim ph
qun cp tnh v 25% vim ph qun mn tnh. Tip xc vi bi hu c
nng thp (nng t 2-9 mg/m3, s lng vi khun 1000 n
100.000/m3 v nng ni c t 50 900 EU/m
3 trong cc chung nui
g, cng nhn thng mc cc bnh vim ph qun cp v mn tnh, cc
triu chng ging hen v cc triu chng kch thch nim mc [96].
Nghin cu ca Eduard W. v cng s (2000) cho thy, nhng ngi
lao ng trang tri tip xc vi bi l lng (aerosol) cha vi sinh vt, bo
nang nm, bi v c v bi hu c xut hin cc triu chng v h hp,
kch thch nim mc mt v mi. Kt qu thy c mi lin quan gia kch
thch mt do bo nang nm, kch thch mi do tc ng ng thi ca bo
nang nm, endotoxin v kh amoniac (NH3); v mc kh NH3 l 2,3 3,9ppm
(thp hn TCVSCP 25ppm) gy kch thch nim mc mi, kch thch hng
vi triu chng ho l do ng thi ht phi ht bi nh v bo nang nm [65].
Sc, theo Brhel 2003, t nm 1996 - 2000 c tng s bnh h hp
ngh nghip mi mc l 2127 trng hp, trong hen ngh nghip l
12,1%, vim mi d ng ngh nghip 5,7% v c hen v vim mi d ng l
3,1%. Bnh hen v vim mi d ng ni trn ch ng sau bnh bi phi silic
(62,0%). Bnh hay gp n nhiu hn nam. Lao ng nng nghip trong
c lao ng ca nhng ngi chn nui l ngh c nguy c cao i vi hen
ph qun v vim mi d ng [63].
Nhng nm gn y, thm mt nguy c na i vi nhng ngi lao
ng lng ngh chn nui gia cm l bnh cm gia cm chng A/H5N1.
Theo thng bo ca T chc sc kho ng vt th gii (OIE) n cui nm
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23
2003 trn th gii c hn 48 quc gia c dch cm gia cm v git hng
trm nghn gia cm. n ngy 6/3/2006, trn ton th gii c 173 ngi b
nhim vi rt cm gia cm H5N1, trong 95 (xp x 55%) ngi cht.
Cho n nay, dch dch cm vn pht trin v cha dp tt c nhiu nc
khc nhau trn th gii.
Theo ti liu ca t chc lin kt cng nhn chn nui, thc phm v
khch sn trn phm vi ton th gii - IUF (Uniting Food, Farm and Hotel
Workers World Wide), chng vi rt cm H5N1 l chng c hi cao ang
ri rc trn ton th gii, kh nng s bin i gen thnh chng mi c kh
nng ly truyn t ngi sang ngi. iu ny lm tng n i s hi xut hin
i dch ton cu nh i dch vo nm 1918 cp i sinh mng ca 50
triu ngi trn th gii. Ngi lao ng lm cng vic chn nui, git m v
ch bin thc phm t gia cm l nhng ngi tip xc trc tip vi cc sn
phm nh: bi phn, lng, cc dch v mu ca gia cm mc bnh, v vy h
c nguy c cao nhim vi rt cm t ng vt v t c th pht tn vo
cng ng xung quanh. Vai tr ca ngi chn nui gia cm c nhc n
nh l con chn dng nc l - i dch cm gia cm ton cu v chnh
h l ngun tip xc u tin.
1.3.2. Nhng nghin cu v nh hng ca iu kin mi trng chn
nui gia cm ti sc khe ngi lao ng ti Vit Nam
Nghin cu nh hng ca mi trng v iu kin lm vic ca ngi
lao ng chn nui gia sc v gia cm Vit Nam hu nh cn rt t. Cc tc
gi: Hong Vn Bnh v CS nm 1978; Bi Th, L Gia Khi v CS nm
1983 trin khai mt s nghin cu v lao ng chn nui gia cm vo
nhng nm 1970 - 1982. Nghin cu cp n thit k chung tri v mi
trng lao ng ti chung tri chn nui g. Cc tc gi nhn thy, ngi lao
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24
ng chn nui lm vic trong mi trng c hi vi bi hi kh vt
TCVSCP (nng bi gp t 4 - 27 ln TCVSCP tri nui g) [50]. Cc
nghin cu v nh hng ca lao ng chn nui gia cm ti sc kho ngi
lao ng ni chung hu nh cha cp n.
Trn Nh Nguyn v CS nghin cu v mi trng lao ng v tnh
trng sc khe ca cng nhn vn th H ni nm 2001 (c th v gia cm).
Tc gi nhn thy c t l kh cao mt s bnh mang tnh cht ngh nghip
nh st cm 19,3%, tiu chy 11,8%, thiu mu 10,2%, nhim k sinh trng
ng rut c bit l giun mc v giun tc 9,5%. Tc hi ngh nghip do
H2S, NH3 l au u 60,4%, kh chu v mi 57,4%, ho 42,6% [42].
Trng Thi H v cng s Trng i hc Nng nghip H Ni xc
nh mt s yu t nguy c nh hng n s pht sinh mt s bnh truyn
nhim ti huyn Lng Sn, tnh Ho Bnh ch ra rng: 10,94% h chn
nui nht gia cm, 89,57% h th rng; v sinh chung tri: 29,3% qut dn
hng ngy, 70,7% ch dn khi qu bn hoc khng dn, 87% khng x l cht
thi trc khi em s dng, 91,9% khng kh trng, 8,1% thnh thong dng
vi bt; khi c dch: sn sng bn chy 79,2%, vt b 16,0%, 4,8% em chn
hoc t. 86,2% khng bo dch; 64,3% khng tiu hu chung tri khi c
dch, 21,9% t mua thuc t iu tr [45].
Trn Thanh H v CS, nm 2005 [29], nghin cu iu kin lao ng,
tc hi ngh nghip ngi lao ng chn nui gia sc, gia cm trong mt s
c s chn nui tp trung. Tc gi nhn thy, cng nhn chn nui gia sc, gia
cm phi lm vic trong mi trng vi kh hu xu, hu nh ngoi tri vo
ma h cc hi kh c hi NH3 v H2S ngng kch thch, mc nhim
vi sinh mc cao, mi trng lao ng c mi rt kh chu. Ngoi ra, cng
nhn thng xuyn phi tip xc vi cc cht st trng trong c
Focmaldehyte. Lao ng ca cng nhn chn nui ch yu l lao ng th
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25
cng nng nhc, t th lao ng xu (xc phn ln xe, ko xe phn, co phn
chung b, ko xe c, gnh). T l mc bnh mi d ng 16,9% (chn nui
g 23%), bnh mt 24%, bnh da 38,1% (cao nht chn nui gia sc 43,6%,
chn nui g 38%), vim khp 35,65%. Ti c s nghin cu khng c mu
gia cm no c vi rt H5N1, ng thi cng khng c cng nhn no b mc
bnh [18][29]. Cc tc gi khuyn ngh cn c nghin cu Tiu chun cho
php i vi bi trong chn nui, thay th s dng Focmaldehyd bng cht t
c hi hn, nng cao hiu bit nhn thc cho ngi lao ng v cc yu t
nguy c ngh nghip v t bo v sc kho bn thn cn c thm nhng
nghin cu theo di sc kho lin tc cho ngi lao ng chn nui gia sc,
gia cm c ch chnh sch ph hp cho ngi lao ng, bo v sc
kho cho ngi lao ng chn nui.
Nghin cu ca Vin v sinh Dch t Trung ng kt lun l dch cm
A/H5N1 trn ngi Vit nam c nhng c im sau:
Dch cm gia cm c lin quan n 2 h thng sng ln l sng Hng
v sng M Kng, l ni c mt nui vt cao hn ni khc. Trong t dch
2 v 3, phn ln cc trng hp nhim bnh xy ra cc h gia nh chn
nui nh l:
- a s cc trng hp nhim cm ngi c lin quan n cm gia cm.
- Dch ch yu tp trung vo cc thng ma ng Xun (khi thi tit
lnh, m). Tuy nhin vn c cc ca bnh xy ra vo cc thi gian khc trong
nm (ph thuc vo tnh hnh dch trn n gia cm ti a phng).
- Bnh xy ra tt c cc la tui t 4 thng n trn 80 tui, tuy nhin
dch tp trung cc la tui di 40, cao nht nhm 10 19 tui.
- Cha thy c s khc nhau gia nam v n v t l mc bnh v t vong.
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26
- Vic xut hin mt s chm bnh gia nh gi l c th yu t di
truyn cng ng vai tr trong s nhy cm vi vi rt cm gia cm. Tuy
nhin, cho ti nay cha tm thy bng chng r rng v s lan truyn gia
ngi v ngi [19].
Theo thng k ca B Y t - Vin V sinh Dch t Trung ng, dch
cm gia cm xut hin u tin khu vc pha Bc (H Ty c) v s cc
ca mc cm gia cm pha Bc nhn chung nhiu hn pha Nam. Trong
s cc tnh thuc khu vc pha Bc (5 tnh): H Ty c, Thi Bnh, Nam
nh, Bc Giang, Hi Dng l cc tnh xut hin dch cm gia cm
khng di 1 ln tnh t nm 2003. Cc tnh ny cng c nhng ngi mc
cm gia cm, trong c nhng trng hp t vong. T thng 12 nm
2003 n nay ti Vit nam xut hin 5 t dch cm gia cm ln. Vit
nam l nc c s lng bnh nhn b nhim cm gia cm ng nht v
cng c nhiu ca t vong do bnh ny nht [13].
Theo nghin cu v kin thc, thi , thc hnh phng chng cm
gia cm ca h chn nui gia cm qui m nh do Vin Pht trin gio dc
(AED) i din cho qu h tr M (USAIDS) thc hin ti tnh Bc Ninh v
Tin Giang vo thng 12 nm 2005: Khi c hi v cc bin php phng
chng cm cho gia cm th 94% cho rng tim vc xin l bin php hiu qu
nht, 76% cho rng nn nui nht gia cm trong chung tri hoc khu vc
c hng ro. Cc bin php phng chng cm gia cm cho ngi nh khng
n tit canh 45% cc i tng nghin cu, khng n tht/cc sn phm gia
cm cha nu chn l 29%. Khi c gia cm nghi ng nhim cm c 60% cho
rng cn phi bo cho c quan th y , 60% chn bin php t tiu hy. Cc
thng tin v cm gia cm ch yu thng qua knh truyn thng bng phng
tin ti vi (76%). V thc hnh phng bnh c 96% h gia nh tim
vacxin cho gia cm [13].
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27
Cng nghin cu v kin thc, thi , thc hnh phng chng cm gia
cm ca h chn nui gia cm qui m nh do CARE Vit nam thc hin ti 4
tnh: Sn La, Bnh nh, Long An, An Giang vo thng 12/2004, thy rng
49% h gia nh chn th gia cm t do. Hu ht nhn thc c cm gia
cm l bnh nguy him cho sc khe con ngi v l mt vn nghim
trng ca Vit nam. 25% i tng nghin cu ngh rng con ngi khng
th nhim cm t gia cm. Nhn chung, a s bit cc ngun ly nhim cm
cho gia cm nh gia cm b bnh (90,5%), dng c chn nui nhim mm
bnh (70,9%). Hu ht ngi dn dng phn ca gia cm bn rung, cho
c n nhng 50% ngi chn nui khng bit phn gia cm l ngun ly
nhim. 50% i tng nghin cu t tiu hy gia cm bnh, cht [13].
Theo Hong Th Minh Hin v CS (2011), nghin cu v mi trng,
sc khe ngi lao ng chn nui gia cm cho thy: 42,5% chung tri khng
ng hng, 63% chung nui gn ni < 10m, 95,9% khng c h kh
trng, cc h gia nh chn nui nh l (100-200 con) hu nh khng tim
chng cho n gia cm; o kh ha hc (H2S, NH3) ti khu vc chn nui u
nm trong TCVSCP, 100% s mu vi sinh mi trng khng kh chung tri
b nh gi l khng m bo v sinh (c v s lng v cht lng vi khun);
V sc khe ngi chn nui: 48,4% NL c triu chng b kch thch nim
mc mt, 41,4% c triu chng kch thch nim mc mi, 23,5% c triu chng
c quan h hp, 11,5% c triu chng bnh ngoi da; nh gi hiu qu can
thip nhn thy c 72,6% NL c nguyn vng c nng cao kin thc hiu
bit v bnh ngh nghip v lin quan ngh nghip [32].
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28
1.4. Cc gii php ci thin mi trng nng cao sc khe ca ngi chn
nui gia cm
1.4.1. Cc gii php ci thin mi trng chn nui gia cm trn th gii
Ti Vng quc Anh c mt s qui nh nh: qui nh chm sc gia
cm nm 1987 Php ch th y v kim sot bnh gia cm, bao gm cc ni
dung: kch thc cu to chung nui; thit k h thng cho n, ung, thng
kh, cch m; ch kim tra n gia cm hng ngy, v sinh kh trng
chung nui; Lut Nng nghip (1968): qui trnh chm sc gia cm v vic
t chc tp hun cc qui trnh ny cho tt c nhng ngi chn nui gia cm.
Lut v bnh ly truyn gia ng vt v ngi (nm 1989) qui nh:
cc bin php kim sot iu kin trong chn nui gia cm phng nga
nhng nguy c e da n sc kho cng ng do dch bnh t gia cm; bt
buc bo co vi h thng th y Nh nc v vic phn lp c cc vi
khun, vi rt t gia cm; v kim sot vic vn chuyn, v sinh, tiu c [44].
1.4.2. Cc gii php ci thin mi trng chn nui gia cm ti Vit nam
Bo v mi trng trong chn nui th y bao gm cc hot ng: qui
hoch cc vng chn nui, git m tp trung; tng cng sn xut sch hn;
x l cht thi cc c s kinh doanh, sn xut, kho nghim thuc th y; x l
cht thi chn nui, git m; v kim sot dch bnh trong chn nui [11][20].
B Nng nghip v Pht trin nng thn xy dng tiu chun iu
kin v sinh th y c s chn nui gia cm v yu cu cc c s chn nui gia
cm tp trung (trang tri) phi t cc tiu chun:
- Phi c cp c thm quyn ph duyt, theo qui hoch ca chnh
quyn a phng.
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29
- Cao ro, thong kh, khng b nhim do bi, khi thi, ha cht
c hi t mi trng xung quanh. a im phi thun tin giao thng
chuyn ch con ging, thc n v sn phm chn nui ra vo tri.
- Phi c ngun nc phc v chn nui. Cht lng nc phi t
tiu chun ngnh.
- Cch nhau khu dn c, cc cng trnh, ngun nc cng cng, ch, l
git m gia sc gia cm. Bn knh t tri chn nui n cc cng trnh trn ti
thiu 500m n trn 1 km ty quy m.
- C hng ro hoc tng kn bao quanh, cch ly vi bn ngoi, m
bo ngn chn c ngi v ng vt t bn ngoi xm nhp vo c s.
Cng ra vo c h st trng v phng tin st trng, tiu c.
- C din tch v iu kin x l cht thi, nc thi theo quy nh.
- C phng lm vic ca cn b th y, ni m, khm lm sng v ly
bnh phm. C ni dng c, thuc, s sch theo di ghi chp tnh hnh sn
xut, dch bnh v s dng thuc, vc xin ca n gia cm.
- C phng thay qun o, kh trng, tiu c trc khi vo khu chn nui.
Ngoi ra, B cn yu cu b tr trong c s chn nui gia cm mt cch
hp l cho cc b phn nh: khu hnh chnh; khu cha dng c thit b, ha cht
v kho cha thc n; khu sn xut; khu x l cht thi, khu p trng, v.v. [14].
V tiu chun khng kh chung nui bao gm: nhit 18 - 320C,
m 55 85%, tc gi 0,5 3m/s, bi trng lng: 1mg/m3,
NH3
10mg/m3, H2S 5mg/m
3 [9].
B Nng nghip v Pht trin Nng thn c quyt nh ph duyt
n tng cng nng lc bo v mi trng nng nghip, nng thn giai on
2010-2020 trong c giao nhim v cho ngnh chn nui th y thc hin:
- Quy hoch cc vng chn nui, khu git m tp trung gn vi bo v
mi trng.
- p dng quy trnh chn nui tt.
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30
- Tng cng cng tc x l cht thi, khu chn nui, git m tp trung,
tiu hy xc gia sc, gia cm.
- Nng cao nng lc qun l mi trng trong th y [5].
Cc qui nh v nhng gii php ch yu l phng trnh bnh cm gia
cm ch cha c nhng gii php c th no v phng trnh chung i vi cc
bnh ngh nghip v nhng bnh truyn nhim khc do chn nui gia cm.
1.5. c im kinh t, vn ha x hi, chn nui gia cm huyn Ph Xuyn
Huyn Ph Xuyn l n v hnh chnh ca Th , nm pha Nam
thnh ph H Ni, cch trung tm Th 40km; pha Bc gip huyn
Thng Tn; pha Nam gip huyn Duy Tin, tnh H Nam; pha ng gip
sng Hng v huyn Khoi Chu, tnh Hng Yn; pha Ty gip huyn
ng Ha, H Ni.
Vi din tch t t nhin 17.104,6ha, Ph Xuyn c dn s gn 20 vn
ngi, t l ngi lao ng trong khu vc sn xut nng nghip chim 60%
tng s lao ng; bnh qun m i nm tng thm khong 2000 lao ng. Hin
nay, Ph Xuyn c trn 995.000 con gia cm, cng tc kim tra gim st dch
bnh c trin khai: Phn cng cn b th y ph trch ti cc x tng
cng kim tra gim st dch bnh, thc hin qui trnh gim st, x l dch
v thc hin ch thng tin bo co dch bnh hng ngy, bo co t xut
khi c dch xy ra. Trong nm 2010 c ti 13.706 con m, 1.598 con cht.
Nhn thc ca mt b phn khng nh h kinh doanh, bun bn, git m v
cng tc tim phng, phng chng dch cn nhiu hn ch v vy nguy c
bng pht dch trn n gia sc, gia cm trn a bn huyn l rt cao.
Chn nui ca Huyn ch yu cn nh l, phn tn, vic lu thng vn
chuyn ng vt, sn phm ng vt din bin a dng, phc tp gy kh
khn cho cng tc qun l gim st dch bnh [54].
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31
Tm li, cc nghin cu v mi trng, sc khe ca ngi lao ng
chn nui gia cm Vit Nam cng cn rt t, mt vi nghin cu trc
y mi ch trin khai cc c s chn nui tp trung c s qun l ca
nh nc. Trong khi dch bnh cm gia cm H5N1 c pht hin ch
yu cc h gia nh chn nui truyn thng, iu kin v v sinh an ton
lao ng cn hn ch. Thc t chng minh nhng c s chn nui p
dng cht ch cc bin php an ton sinh hc th dch cm khng xy ra
[8]. Bo co kt qu nghin cu v bnh cm gia cm ca Vin Th y
Trung ng nhn nh: cm gia cm tr thnh dch a phng Vit
Nam v dch cm gia cm (CGC) a phng s gy ra cc ca bnh l t
ngi v c nguy c gy ra i dch ngi. Mt nghin cu ti 130 h
gia nh chn nui truyn thng ti tnh Thi Bnh ngay sau khi ht dch
thy 8,4% h chn nui g c huyt thanh dng tnh v 69,5% h c
huyt thanh dng tnh khi nui ln ln g vi vt.
Nh vy kh nng mi trng chn nui theo kiu h gia nh l b
nhim, vn l nhim ang mc no? Chng gy nh hng n sc
kho ca con ngi n u? s cn thit phi c mt nghin cu iu tra,
qua xut cc gii php can thip c tnh kh thi nhm ci thin c
mi trng, iu kin lm vic, nng cao thc bo v sc kho phng trnh
bnh tt ca ngi chn nui gia cm ni ring v cng ng ni chung. Do
vy cn c nghin cu nh gi cc yu t mi trng v iu kin lm vic
trong mi lin quan vi bnh tt (nguy c ngh nghip) ca nhng ngi lm
vic chn nui gia cm cc h gia nh, c bit cn quan tm n yu t
lin quan n bnh truyn nhim v cc xut gii php d phng, bo v
sc kho cho ngi lao ng. Vi iu kin thi gian v ngun lc c hn
chng ti s tin hnh mt nghin cu can thip c ch ch ti khu vc dn
c nng thn thuc Huyn Ph Xuyn, H Ni.
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32
Chng 2
I TNG V PHNG PHP NGHIN CU
2.1. i tng nghin cu
- Ngi trc tip chn nui gia cm v ton b cc thnh vin thuc h
chn nui gia cm.
- iu kin v mi trng ti cc chung/ tri v mi trng xung
quanh thuc h chn nui gia cm.
Tiu chun la chn i tng nghin cu
i vi ngi trc tip chn nui gia cm.
a) Tiu chun la chn
- Tui i t 18 n 65 tui (di 18 tui l tui tr em v hc sinh ph
thng; nng thn thng thng sau 65 tui mi ngh lao ng).
- Thi gian trc tip tham gia chn nui gia cm ti thiu l 1 nm.
- Trong mt tun cho gia cm n v dn dp v sinh chung tri chn
nui gia cm t nht l 4 ln/tun.
- ng hp tc tham gia nghin cu.
b) Tiu chun loi tr
- Ngi trn 65 tui v di 18 tui.
- Ngi mi tham gia chn nui gia cm thi gian cha mt nm.
- S ln cho gia cm n v dn chung t hn 4 ln/ tun.
- Khng hp tc tham gia nghin cu.
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33
i vi cc thnh vin khng trc tip tham gia chn nui gia cm:
Khm v kim tra sc khe cho tt c cc thnh vin trong cc h chn
nui gia cm c chn vo nghin cu.
i vi iu kin v mi trng ti cc chung/ tri thuc h chn nui
gia cm
a) Tiu chun la chn
- Chung/ tri ti cc gia nh chn nui gia cm (c g, vt, ngan v
ng ng) ti thiu l 3 nm.
- H c s lng n gia cm nui trong chung t 100 n 200
con/n (h chn nui gia cm nh l).
b) Tiu chun loi tr
- Cc h gia nh chn nui gia cm di 3 nm.
- H c s lng gia cm ti cc chung/tri di 100 con/n hoc
trn 200 con/n (y l m hnh gia tri hoc trang tri).
- Cc h ch p v bn gia cm ging (chuyn p trng v nui gia
cm con).
- Cc thng li, chuyn bun bn gia cm.
2.2. a im nghin cu
Nghin cu c tin hnh ti hai x i Xuyn v Hng Thi thuc
huyn Ph Xuyn, thnh ph H Ni (tnh H Ty c). Hai x khng st cnh
vi nhau; c iu kin a l, kinh t v dn c tng t nhau.
Bc 1: chn 02 x iu tra m t, ct ngang theo cc ni dung m
ti thc hin.
Bc 2: s chn mt x can thip (chn x c iu kin v sinh km hn).
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34
- T kt qu ca bc 1, chng ti nhn thy, Hng Thi l x c iu
kin v sinh km hn c th hin:
+ V mi trng
- X Hng Thi l c t l chung/ tri bn nhiu hn (t l chung bn
chim 97,8% so vi 82,2%).
+ V vi khun
- Vi khun hiu kh: Ti x Hng Thi nhiu gp 5,2 ln so vi i Xuyn.
- Vi khun tan mu: Hng Thi nhiu gp 2,2 ln so vi i Xuyn.
- Nm mc: Hng Thi nhiu gp 3 ln so vi i Xuyn.
+ V bnh tt
- Hng Thi c t l mc cc bnh hen ph qun, bnh ngoi da, nm
mng, bnh mt cao hn i Xuyn mc c ngha thng k (p< 0,05) l
nhng bnh c lin quan n mi trng chn nui gia cm.
+ Cc cn b th y, y t cng sn sng ng h nghin cu can thip.
Vi l do trn chng ti chn Hng Thi lm x can thip v i
xuyn lm x i chng.
2.3. Phng php nghin cu
2.3.1. Thit k nghin cu
Thit k nghin cu c s dng ph hp vi 2 giai on nghin cu
ca ti:
- Giai on 1: thit k nghin cu m t ct ngang.
- Giai on 2: thit k nghin cu can thip cng ng c i chng.
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35
2.3.2. Giai on 1: nghin cu m t ct ngang
2.3.2.1. S thit k nghin cu m t ct ngang
S 2.1: M hnh m t ct ngang
2.3.2.2. C mu nghin cu
n v tnh c mu l H gia nh: c mu nghin cu c tnh theo
cng thc c tnh mt t l trong qun th vi chnh xc tuyt i [47]:
2
2
2/1
1
d
ppZn
Trong :
p: l t l h gia nh chn nui khng t tiu chun v sinh vi
p = 97% (0,97) [2].
Kho st v nh gi s
b thng tin a phng
Chn mu c ch ch
(2 x/huyn)
iu tra x th nht
(Chn HG v i tng NC)
iu tra x th hai
(Chn HG v i tng NC)
Chn x can thip
M t v so snh
Chn x i chng
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36
Z1-/2: = 1,96, tng ng vi mc ngha thng k = 0,05
tin cy 95%.
d: chnh xc tuyt i ca p, chn d = 5%.
Kt qu tnh cho n xp x bng 45, m bo hiu qu thit k chng
ti nhn c mu tnh c vi hiu lc thit k (DE) bng 2. Nh vy s h
gia nh ca c hai x c la chn tham gia vo nghin cu l 90 h, m i
x chn 45 h cho nghin cu nh gi tnh trng v sinh chn nui. S h
ny c chn ngu nhin n, t danh sch m cn b th y cung cp v
theo bo co ca 2 x th tt c cc thnh vin thuc 90 h c phn b theo
quan h vi ch h trong bng sau:
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37
Bng 2.1: Phn b s thnh vin trong 90 h gia nh nghin cu hai x
la chn (i Xuyn, Hng Thi) theo quan h vi ch h
Thnh vin trong
h gia nh
i Xuyn Hng Thi Tng
n % n % n %
Ch h 45 21,4 45 20,8 90 21,1
V/chng 45 21,4 45 20,8 90 21,1
Con 90 42,9 94 43,5 184 43,2
B/m 19 9,0 23 10,6 42 9,9
Anh/ch/em 4 1,9 3 1,4 7 1,6
Chu 7 3,3 6 2,8 13 3,1
Cng 210 100 216 100 426 100
i vi i tng l ngi chn nui trong h gia nh c la chn
phng vn v kin thc, thc hnh: trong tng s 426 thnh vin trong 90
h gia nh c tham gia nghin cu, cc i tng c iu tra l ngi
trng thnh 18 n 65 tui, phi c thi gian chn nui t 1 nm tr ln, cho
n cng nh thu dn v sinh chung tri t nht 4 ln/tun, chn ra trong cc
h gia nh tng cng l 185 ngi. Phng vn cc i tng ny v kin
thc v sinh chn nui v bnh lin quan n chn nui gia cm.
i vi ni dung khm sc khe: khm sc khe cho ton b 426
ngi trong 90 h gia nh c chn vo nghin cu.
i vi kho st bng o c cc yu t vi kh hu v hi kh c pht
sinh ti ni nui nht gia cm cc h gia nh: do iu kin v kinh ph v
thi gian c hn nn nghin cu ch c tin hnh kho st ngu nhin 46
mu thuc 46 h trong 90 h chn nui gia cm chn.
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38
- S dng k thut ly mu, phn tch mu theo Thng qui k thut
Y hc lao ng, V sinh mi trng, Sc khe trng hc ca Vin Y hc
lao ng v V sinh mi trng, xut bn nm 2002.
- S mu xt nghim yu t ha hc: 46 mu nh lng nng NH3,
H2S, CO2.
- S mu o yu t vt l: 46 mu o vi kh hu (nhit , m,
vn tc gi).
- S mu xt nghim yu t vi sinh vt: 46 mu xt nghim vi khun
hiu kh, nm mc, vi khun gy tan mu.
2.3.2.3. K thut chn mu nghin cu
Chng ti s dng k thut chn mu nhiu giai on:
- Giai on 1 - chn huyn nghin cu: chn mu c ch ch, l
huyn Ph Xuyn thuc thnh ph H Ni, l do chn huyn Ph Xuyn
nghin cu v:
+ L mt huyn thuc ng bng Bc b, chn nui nhiu gia cm v
l mt trong nhng a phng cung cp nhiu sn phm t gia cm (tht,
trng, con ging) cho thnh ph H Ni v cc tnh ln cn.
+ T nm 2003 c xut hin dch cm gia cm H5N1.
+ Chnh quyn a phng cc cp nhit tnh ng h nghin cu.
- Giai on 2 - chn x nghin cu: chn ch ch ly 2 x, l x
i Xuyn v Hng Thi, nhng x ny pht trin mnh kinh t chn nui
gia cm, tuy nhin cn c nhiu h gia nh chn nui nh l t 100 n
200 con/n.
- Giai on 3 - chn h gia nh nghin cu theo cch chn ngu nhin
n t danh sch ca th y x cung cp chn ra 45 h gia nh cho m i
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39
x. Kt qu phn b s h gia nh ca tng x, tng thn chn vo nghin
cu c trnh by trong bng 2.2:
Bng 2.2: Phn b s h gia nh ca 2 x c chn vo
nghin cu theo thn
X i Xuyn X Hng Thi
Thn S HG Thn S HG
C Trai 3 Duyn Trang 15
a Cht 6 Duyn Yt 18
Kiu ng 5 Lt Dng 12
Thi Lai 18
Thng Xuyn 13
Cng 45 45
- Giai on 4 - chn i tng tham gia nghin cu: t nhng h gia
nh c chn, chng ti chn nhng ngi c tiu chun t ra phng
vn tm hiu kin thc v thc hnh ca h v v sinh v phng chng bnh
do gia cm gy ra (185 ngi).
- i vi kho st mi trng: do iu kin kinh ph c hn chng ti
chn ngu nhin 23 h gia nh t 45 h gia nh ca m i x c chn vo
nghin cu, theo cch bc thm trn danh sch c tin hnh nh lng
cc yu t mi trng lin quan n chn nui gia cm. Cc mu o c
thc hin bi cc cn b k thut o c mi trng ca Trung tm dch v
Khoa hc k thut sc khe v mi trng thuc Vin Y hc lao ng v V
sinh mi trng. Tt c u c thc hin theo quy nh Thng quy k
-
40
thut ca Vin Y hc Lao ng v V sinh mi trng nm 2002. K thut
ly mu xem phn ph lc 6.
Tiu chun nhim vi sinh vt trong khng kh: Cho n hin nay
chng ta cha c tiu chun qui nh cht lng khng kh da theo lng vi
sinh vt trong 1m3 khng kh. Chng ti ly tiu chun v nm mc trong
khng kh theo Romanovic:
Bng 2.3: Tiu chun nm mc trong khng kh theo Romanovic
Mc v sinh Tng s nm mc/m3
Rt tt 0
Tt 308
Kh 770
Xu > 770
Tiu chun v vi sinh vt trong khng kh theo tiu chun ca Safir:
Bng 2.4: Tiu chun cht lng khng kh trong nh ca Safir
Mc Tng s vi sinh vt/m3 Tng s cu khun tan mu/m
3
Sch < 1500 < 16
Bn > 2500 > 36
+ Khm sc khe tng qut cho cc thnh vin h gia nh: Khm
lm sng cho ton b 426 thnh vin trong 90 h gia nh hai x nghin cu
ti trm y t x do cc bc s ca bnh vin Nng nghip thuc B Nng
nghip v Pht trin nng thn thc hin. Sau phn tch tnh trng dinh
dng (da theo phn loi BMI ca t chc Y t th gii), tnh hnh bnh tt
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41
v tnh trng sc khe theo hai nhm i tng: 185 i tng trc tip tham
gia chn nui gia cm ( tiu chun) c chn tham gia nghin cu v cc
i tng cn li trong 90 h gia nh.
2.3.2.4. Cng c thu thp thng tin v kin thc, thi v thc hnh ca
i tng trc tip chn nui
- B cu hi phng vn kin thc, thi v thc hnh ca i tng
trc tip chn nui (ph lc 1): b cu hi ny trc khi tin hnh nghin cu
c phng vn th ti thc a (pre-test). Sau khi phng vn th b cu
hi c b sung nhng thng tin cn thiu v chnh sa li ngn t khi
hi ngi c phng vn d tr li v cung cp nhng thng tin cn thit
mt cch chnh xc. B cu hi ny cng c s dng 2 ln trc v sau
trong nghin cu can thip nh gi hiu qu can thip.
- Bng kim nh gi cm quan thc trng iu kin v sinh chn nui
ca h gia nh (ph lc 2, 3): c thit k da trn mc tiu cng nh cc
ch s nghin cu v cng c th nghim ti thc a v c b sung,
chnh sa trc khi tin hnh nghin cu chnh thc. Bng kim cng c
s dng trong nghin cu can thip.
- Bnh n nghin cu (ph lc 4): bnh n c thit k da trn tiu
ch khm sc khe cho cc i tng thnh vin trong h gia nh. Mu bnh
n c trch t bnh n mu ca bnh vin Nng nghip.
2.3.2.5. Cc ch s nghin cu cho mc tiu 1
+ c im v sinh chn nui ca cc h gia nh
- T l h gia nh nui gia cm nht trong chung.
- T l h gia nh c chung/ tri nui gia cm xy kin c.
- T l h gia nh c chung/ tri nui gia cm cch nh di 1m.
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42
- T l h gia nh c chung/ tri nui gia cm cch nh bp di 1m.
- T l h gia nh c chung/ tri nui gia cm cch ging nc n, b
nc di 5m.
- T l h gia nh gia nh c chung/ tri nui gia cm cao ro, sch s.
- T l h gia nh c rnh thot nc thi t chung/ tri nui gia cm.
- T l h gia nh c h cha nc thi t chung/ tri nui gia cm.
- T l h gia nh c h phn gia cm.
+ Kin thc v sinh chn nui gia cm ca ngi trc tip tip xc
- T l i tng chn nui gia cm c kin thc v thc hnh (ng,
sai) v phng chng bnh t gia cm ly sang ngi.
- T l i tng chn nui c thi x tr ng khi gia cm b cm
(tiu hy ton b n gia cm).
- T l i tng chn nui c s dng t nht 1 phng tin bo h lao
ng (eo khu trang) khi chn nui gia cm.
- T l i tng chn nui c thi v hnh vi thng xuyn tiu
c cho chung tri nui gia cm.
+ Thc trng nhim mi trng chn nui
- T l chung nui gia cm ca cc h gia nh c nng bi, hi
kh c (NH3, H2S, CO2), mt vi sinh vt vt tiu chun ti a cho php
hoc tiu chun khuyn co.
+ Tnh trng sc khe, bnh tt ca cc thnh vin thuc cc h gia nh
nghin cu
- Tnh trng dinh dng (ch s khi c th = BMI): Cch tnh v
phng php nh gi chng ti da vo phng php nh gi tnh trng
dinh dng ca NXB Y hc [38].
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43
Tnh ch s khi c th (BMI: Body Mass Index)
Trong : W l trng lng c th (Tnh bng ki l gam)
H l chiu cao ca c th (Tnh bng mt)
Ch s khi c th c nh gi theo bng sau:
Bng 2.5. nh gi ch s khi c th theo chun ca T chc Y t Th
gii (WHO) v ginh ring cho ngi chu i vi ngi trng thnh
(IDI & PRO):
Phn loi WHO BMI (w/h) IDI&WPRO BMI (w/h)
Gy III < 16 < 16
Gy II 16 16,9 16 16,9
Gy I 17 - 18,5 17 18,4
Bnh thng 18,5 - 24,9 18,5 - 22,9
Tha cn 25 - 29,9 23 - 24,9
Bo ph I 30 - 34,9 25 - 29,9
Bo ph II 35 - 39,9 30 34,9
Bo ph III >= 40 >= 35
- T l mc cc chng bnh [15], phn b theo i tng trc tip hay
gin tip tham gia chn nui gia cm ti cc h chn nui.
2.3.3. Giai on 2: nghin cu can thip truyn thng thay i hnh vi ca
ngi chn nui gia cm
2.3.3.1. S thit k nghin cu can thip [45]
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44
S 2.2: M hnh nh gi so snh trc sau v so snh
vi nhm chng [22]
2.3.3.2. C mu nghin cu
Trn c s c mu chn giai on 1 ca nghin cu, chng ti tin
hnh nghin cu can thip ti 45 HG x Hng Thi, cn 45 HG x i
Xuyn chn lm i chng nhm nng cao kin thc v thc hnh phng
bnh - bo v sc khe cho ngi chn nui, ci thin iu kin mi trng
lm vic, mi trng chung tri.
So snh
trc sau
(H2)
So snh
trc sau
(H1)
H1 S liu iu tra sau mt thi gian
(tng ng vi thi gian ca
nhm can thip)
So snh
2 nhm
(H3)
Nhm chng (khng can thip)
S liu iu tra c bn
liu iu tra c bn
Nhm can thip
S liu iu tra c bn
S liu iu tra sau
can thip
Can thip
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45
2.3.3.3. Ni dung can thip
Ti liu s dng: ti liu hng dn An ton sc khe trong chn nui
gia cm ca Vin nghin cu khoa hc k thut Bo h Lao ng thuc
Tng lin on lao ng Vit Nam.
Nhng ni dung truyn thng c th:
- Kin thc v thc hnh v tc hi ca cc bnh gia cm ly lan sang
ngi, nguyn nhn, c ch v phng thc mc bnh.
- Bnh ngh nghip v lin quan ngh nghip trong chn nui gia cm
- Bin php d phng.
- Nhng gii php ci thin iu kin mi trng chn nui gia cm
hp v sinh.
- Qui trnh thc hnh chn nui gia cm an ton ti h gia nh.
2.3.3.4. Phng php can thip
- Truyn thng gio dc sc kho
Tp hun kin thc, tho lun, trao i trc tip.
Pht t ri, ti liu cho 45 h gia nh; i pht thanh v
nguy c ly bnh t gia cm trong c cm H5N1 t gia
cm sang ngi, bin php d phng v cch x tr khi c gia
cm b mc bnh.
Cc hot ng:
1) Chun b ti liu, in t ri.
2) T chc lp tp hun: hai lp cho cc thnh vin trc tip
tham gia chn nui (tham gia phng vn, iu tra) thuc 45
h gia nh.
Thi gian tp hun: 2 ngy/1 lp.
a im: ti x
3) Pht t ri cho tng h gia nh.
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46
2.3.3.5. Ngi thc hin
- Cc cn b thuc nhm nghin cu.
- Cc cn b th y ca 2 x.
- Cn b pht thanh ca 2 x.
2.3.3.6. Phng php thu thp thng tin
Phng vn trc tip nhng i tng chn nui gia cm theo b cu hi
v bng kim nh gi tnh trng v sinh chung/ tri nui gia cm nh trong
giai on 1 ca nghin cu.
2.3.3.7. Cng c thu thp thng tin
S dng b cu hi phng vn h gia nh, v bng kim nh giai
on 1 (ph lc 1).
2.3.3.8. Cc ch s nh gi hiu qu can thip (so snh trc can thip vi
sau can thip; so snh gia nhm chng v nhm can thip).
- T l h gia nh ci to chung/ tri nui gia cm cao ro, sch s
(khng m t, sng sa, thng thong v khng c bi phn).
- T l h gia nh lm rnh thot nc thi t chung/ tri nui gia cm.
- T l h gia nh o h cha nc thi t chung/ tri nui gia cm.
- T l h gia nh xy h phn gia cm.
- T l i tng chn nui gia cm c kin thc v thc hnh v
phng chng bnh t gia cm ly sang ngi (trnh mi nguy him, c cc
bin php phng bnh, bo v sc khe).
- T l i tng chn nui c thi x tr ng khi gia cm b cm
(tiu hy ton b n gia cm, kh trng, ty u chung/ tri v ni ).
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47
- T l i tng chn nui c s dng phng tin trang b bo h lao
ng (eo khu trang, mang knh, i ng, gng tay) khi chn nui gia cm.
- T l i tng chn nui c thi v hnh vi thng xuyn tiu
c cho chung/ tri nui gia cm bng dn dp sch s hng ngy v rc vi
bt hng tun.
- Ch s v hiu qu can thip ca nhm i chng, nhm can thip v
sau can thip gia nhm can thip v nhm i chng
2.3.3.9. X l s liu nh gi hiu qu can thip
Cc s liu sau khi thu thp c nhp vo phn mm EpiData 3.1, sau
chuyn sang phn mm SPSS 18.0 tnh cc ch s theo mc tiu nghin
cu, p dng cc thut ton thng k tnh v so snh cc: tn s; t l phn
trm; ch s hiu qu can thip (so snh trc sau) v hiu qu can thip gia
nhm can thip v vi nhm chng theo m hnh nh gi hiu qu can thip.
+ Ch s hiu qu can thip trc- sau: HQCT(T-S) nhm chng
[23] H1 = {(t l iu tra sau t l iu tra trc)/t l iu tra sau} x 100%.
+ Ch s hiu qu can thip trc- sau: HQCT(T-S) nhm can thip H2
= {(t l iu tra sau can thip t l iu tra trc)/t l iu tra sau} x 100%.
+ Ch s hiu qu can thip so vi nhm chng: HQCT(CT-C)
H3 = {(t l iu tra sau ca nhm can thip t l iu tra sau ca nhm
chng)/t l iu tra sau ca nhm can thip} x 100%.
2.3.4. Khng ch sai s trong nghin cu
khng ch sai s trong nghin cu, chng ti thc hin:
- Thit k b cu hi iu tra cng nh bng kim tht cht ch, m
bo y thng tin, cu hi d hiu v d tr li trnh sai s khi thu thp
thng tin.
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48
- K thut ly mu cng nh phn tch mu theo ng Thng qui k
thut Y hc lao ng, V sinh mi trng, Sc khe trng hc ca Vin Y
hc lao ng v v sinh mi trng trnh sai s h thng.
2.3.5. Mt s khi nim s dng trong nghin cu
- H gia nh: l nhng ngi sng chung mt mi nh, cng chia s
mi quyn li kinh t.
- H gia nh chn nui gia cm: l nhng h gia nh nui t nht t
100 n 200 con/n.
- Tiu chun chn on cc bnh theo Bch khoa th bnh hc.
2.3.6. o c nghin cu
- Nghin cu phi c php ca chnh quyn a phng ng .
- H gia nh nghin cu ng v t nguyn tham gia nghin cu.
- Kt qu nghin cu phi bo co li cho chnh quyn a phng v
nhn dn trong a phng bit.
- C th p dng nhn rng kt qu nghin cu sang a phng khc
trong huyn.
- Trong qu trnh khm sc khe s khm tt c cc i tng thuc h
gia nh chn nui, khng phn nhau i x.
- Cc i tng c cc vn v sc kho s c thng bo, hng
dn, gii thiu n iu tr ti cc c s y t ph hp.
- Sn sng t vn cho cc i tng khi h c yu cu.
2.3.7. Hn ch ca ti
- V iu kin v kinh ph nn cha t chc khm cn lm sng cho cc
i tng nghin cu.
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49
- Thi gian nghin cu cha nh gi hiu qu thay i v sc
khe ca ngi lao ng chn nui sau khi can thip.
- Mt s cu hi khng thu c cu tr li t i tng nn kt qu
phng vn i vi mt s cu hi cc mu s khng hon ton nh nhau,
nhng vn m bo c mu s l thng k.
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50
Chng 3
KT QU NGHIN CU
3.1. Thng tin chung v cc thnh vin thuc cc h gia nh tham gia
nghin cu
101
109
113
103
94
96
98
100
102
104
106
108
110
112
114
i Xuyn Hng Thi
Nam
N
Biu 3.1: Phn b cc thnh vin h gia nh theo gii tnh
Trong tng s 426 i tng ca hai x nghin cu, t l nam gii chim
50,2%, n chim 49,8%. S i tng tham gia nghin cu x i Xuyn
chim 49,3% v x Hng Thi chim 50,7%. S khc nhau v gii tnh ca
cc thnh vin cc h chn nui gia cm tham gia nghin cu ti 2 x l
cha c ngha thng k (p > 0,05). Xt 45 h gia nh chn nui thuc 2 x
c tng s cc thnh vin l tng ng.
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51
Bng 3.1: Phn b cc thnh vin h gia nh theo nhm tui
Nhm tui
i Xuyn
(n=210)
Hng Thi
(n=216) p
Chung 2 x
(n = 426)
n % n % n %
Di 6 tui 11 5,2 12 5,6
(2 = 0,133;
p > 0,05
23 5,4
6 n di 18 tui 44 21,0 47 21,8 91 21,4
18 - 65 tui 143 68,1 146 67,6 289 67,8
Trn 65 tui 12 5,7 11 5,1 23 5,4
Trong tng s 426 i tng nghin cu ca hai x tham gia nghin
cu, nhm tui lao ng (18 n 65 tui) chim i a s (289/426 ngi =
67,8%), nhm tui i hc (6 n di 18 tui) chim 21,4%. S khc nhau
