DIEU TRA NGUON GOC VU D|CH TA TAI MIEN BAC VIET NAM, 2007 - 2009 Tran Nhu Duong. \g<"> Huy Tii, Nguyen Thi Binh Minh, Nguyen Triin IIien
I "ien I e sinh Dich te Tiling uong, Hit Soi TOM TAT
Benh ta do vi khuln Vibrio cholerae nhdm 01 hoac 0139 gay ra, benh lay theo dudng tieu hda, chu yeu do sir dung ngudn nude hoac thuc pham bi d nhilm vdi tac nhan gay benh. Ti> thang 10 nam 2007 din thang 6 nam 2009, mot vu dich ta Idn xay ra tai mien Bic Viet Nam vdi hon 8.000 ngudi mlc benh, 1 trudng hpp ti> vong Nghien ciru nay sir dung phuong phap md ta clt ngang kit hpp lay mlu benh phim xet nghiem tim can nguyen nhlm tim hilu ngudn gdc vu ciia vu dich. Kit qua cho thly: Trong 15 ngay dlu cac dot djch 59.8% trudng hop benh nhan cd an thit chd, 54,6% an mlm torn va 58,8% an rau thom/rau sing trong vdng 5 ngay trudc khi phat benh. Khdng tim thly su d nhilm vi khuln ta d cac ngudn nude an udng, sinh hoat trong giai doan 2 tuln dlu ciia dich. Khdng phat hien dupe su d nhilm vi khuln ta trong rau thom/rau sdng tai chp dlu mdi, vudn rau/vimg chuyen canh rau (0/1940 mlu). Khdng phat hien dupe su d nhiem vi khuln ta trong cac mlu mlm torn thu thap dupe trong vudich (0/111 mlu). Phat hien vi khuln ta nhdm 01, tip huyet thanh Ogawa trong mptso mlu thit chd sdng, chin tai quan an, cua hang, chp, Id gilt mo chd cd lien quan dich ti din ca benh trong vu dich (7/90 mlu).
Phat hien vi khuln ta nhdm 01, tip huylt thanh Ogawa trong tam bong ngoay hau mdn mot sd chd tai co so gilt mo chd, noi nudi nhdt phan phdi chd lam thuc phim (4/240 mau) Nhu vay. nhieu kha nang mot sd chd b| nhilm vi khuln ta dupe su dung lam thyc phim cd thi la nguon gdc ciia vu djch ta tai mien Bic Viet Nam, 2007 - 2009 Tu khoa Dich ta Viet Nam, vi khuln ta, ngudn nude, rau, thjt chd, mlm torn.
I. DAT VAN DE
Ta la mot benh truyen nhiem lay qua dudng tieu hoa do cac chung vi khuan ta IV- hrio cholerae nhdm ()l hoac CM 3d giiy ra. vdi cac trieu chiing chinh la tieu chay toe nude cap tinh dan tdi mat nude va rdi loan dien giai tram trong. Benh ta lay lan nhanh va cd kha nang gay thanh dich Idn vdi ty le tu vong cao.
dac biet lii tai cac nude ngheo. Lich sir da ghi nhan 7 vu dai dich la tren the gidi khien hang chuc nghin ngudi tir \ong | l]. Cho den ngay nay. dich la van luu hanh khap the gidi va lit mot trong nhung nguyen nhan giiy tu vong cao tai nhieu quoc gia. Nam 2007. tdng sd ca mac ta tren toan the gidi la I77.963. tir vong 4.03 I
ghi nhan lai 53 quoc gia. Trong dd. Chau A chidm 6.4% vdi I 1.325 ca mac, chel 24 |2|.
Trong nam 2008. mot vu dich ta Idn da xay ra tai Zimbabwe vdi 16.14 1 ca nghi ngd mac benh, 775 trudng hop tir vong (ly Ic chct/mac la 4.8%) [3]. Nhin chung dich tii tren the gidi da cd xu hudng tang lien tuc trong nhung nam tro lai day ca ve quy md va pham vi giiy djch.
Thong ke ciia Td chuc Y tc The gidi cho thay.
chi tinh rieng giai doan tir 2004-2008 sd ca benh ta tren the gidi da lang 24% so voi giai doan tii nam 2000-2004.
Tai Vict Nam. benh ta la nguyen nhan giiy tieu chay cap quan trong hon mot the ky qua vdi nhieu vu dich Idn xay ra trong Ijch sii' duoc ghi nhan. Mien Nam. mien Trung. benh Tac gia: Tran Nhu Duong
Dia chi: \ ien ve sinh dich tc trung uong. So 1 Yersin. Ha noi Dien thoai: 0988761312
Lmail: trannhuduong a gmail.com
3d Tap chi Y hoc dir phong. 'Tap XX. so' 6 (1 14)
ta thuong xay ra dudi dang dich luu hanh dja phuong. con d mien Bac van chua cd hang chung khang djnh benh ta luu hanh. Tu nam 2000 tro lai day. djch ta van xay ra rai rac d mot so tinh mien Bac nhung nhanh chdng duoc khdng chd 11], Sau 2 nam 2005 - 2006 khdng ghi nhan ca mac ta nao tren toan quoc.
bat ngd nam 2007, 2008. 2009 cac dot djch ta da lien tiep xay ra tai nhieu tinh. thanh phd mien Bite Vict Nam vdi nhieu nghin ca mac gay anh hudng Idn tdi sue khde cdng ddng.
Chung tdi tien hanh nghien ciiu nay nham dieu tra xac dinh ngudn gdc cua vu djch ta mien Bac Vict Nam nam 2007 2009.
II. PHI "ONG PHAP NGHIEN (It 2.1. Doi tuong nghien ciiu
Benh nhan mac ta lai mien Bac Vict Nam irong vong 15 ngay dau cua cac dot djch nam 2007 - 2009. Benh nhan dupe lua chon dua vao nghien cuu theo diing djnh nghTa ca benh ciia td chiic y tc the gidi (Wl lO) va Bd Y le.
Cac mau nude: nude sinh hoat. nude thai, nude ao hd tai khu vuc d djch.
Cac mau rau thorn, ran sdng cac loai Man thjt chd cac loai.
Mau phan chd (mau ngoay hau mdn).
Mot so man thuc pham khac nghi ngd cd lien quan: mam torn. biin. mot so thuy hai san (torn. muc. de. sd).
2.2. Dia diem nghien ciiu
22 tinh/thanh phd mien Bac. Vict Nam cd dich tii trong vu djch nam 2007- 2009.
Cac ciin hang lai Ha Ndi cd lien quan dich te tdi mot so benh nhan mac la.
Cac cho dau mdi. viing chuyen canh.
trang trai trdng rau tai mot sd tinh/thanh phd:
llii Noi. 1 lai Duong. Hai Phong...
Mdi so cua hang ban thjt chd. co so giet md cho tai I la Ndi.
Khu nudi nhdt chd phan phoi liuu thuc pham cho mot so tinh mien Bac tai huyen I lau I oc tinh Thanh 1 Ida.
2.3. Thdi gian nghien ciru
Trong suot thdi gian cd djch: 2007 2009.
2.4. Thiet ke nghien ciiu
Nghien ciru md ta hoi ciru va dieu tra cat ngang ca benh. vu djch.
Nghien ciru cat ngang lay man benh pham nghi ngd xet nghiem tim can nguy en.
2.5. Cong cu va ky thuat thu thap thdng tin/
xet nghiem
* Cdng cu thu thap thdng tin:
Phieu dieu tra ca benh dupe thiet ke san.
Bao cao dich hang ngay, hang tuan.
hang thang va bao cao long hop ca benh. vu djch tir cac tinh giri len. So kham benh. sd vao vien, benh an benh nhan lai cac co so dieu trj cd tiep nhan benh nhan ta,
* Ky thuat thu thap thdng tin
Phong van true tiep benh nhan dua tren phieu dieu tra dupe thiet ke san.
Thu thap thdng tin djch te ciia benh nhan dua tren cac bao cao tdng hpp ca benh, vu djch tir cac tinh giri len ciing nhu tir benh an tai cac co so dieu trj benh nhan ta.
l ay man benh pham va xet nghiem:
Cac man benh phiim cd lien quan bao gdm:
mau nude, man ran. man phan va cac man benh pham khac nghi ngd cd lien quan dupe thu thap thep diing quy trinh cua phong thi nghiem. Cac man benh pham sau khi thu thap dupe bao quan va van chuyen ngay ve phong thi nghiem cua Vien Ve sinh Djch le Trung uong. Cac xet nghiem tim t'ihno Cholerae dupe tien hanh theo thudng quy tai phong xet nghiem vi khuan dudng rupt, Vien Ve sinh Djch te Trung uong.
2.6. Xu ly va phan tich so lieu
So lieu dupe quan ly bang phan mem Microsoft Access va dupe xir ly. phan tich bang phan mem Stata 9.0.
Net qua dupe trinh bay dudi dang bang.
dd thj. bieu do. ban do.
Tap chi Y hpc dir phone. Tap XX. sd' 6(114) 37
HI. Kill Ql A
Mot sd loai thuc pham benh nhan da an trong vdng 5 nga\ trudc khi khoi phat . Bang 1. Ty le cac thu-c pham benh nhan da an trong vong 5 ngay trird-c khi khdi phat ciia cac
trirdng hop mac ta trong 2 tuan dau cac dot djch nam 2007 - 2009 Thuc phim benh ^
nhan da an trong (n-64) Dot 2
(n=12) Dot 3
(n=21) Tong so (n=97) vdng 5 ngay trudc g£
khi khdi phat llrg,ng Iwcrng %
S° %
twang
s° %
Iwc/ng
Thit chd 41 64,1 10 83,3 7 33.3 58 59,8
Mam torn 38 59.4 8 66.7 7 33.3 53 54.6
Rau sdng 35 54.7 9 75 13 61,9 57 58,8
Bun 12 18,8 0 0 2 9.5 14 14.4
Long km, tiet canh 0 0 0 0 1 4.8 1 1,0
Thuy, hai san 21 32,8 2 16,7 1 4.8 24 24.7
t'ac dieu tra ca benh. vu djch trong 15 ca benh duoc dieu tra, cd tdi 59.8% cidi tuong ngay dau ciia cac dot dich deu cho thay thjt cd an thjt chd. ty Ic nay vdi mam torn lii 54.6%
chd. mam torn va rau thorn/rail song lit cac va rau (hom rausdng lii 58.8% (bang I ).
thuc phiim benh nhan da an trong vdng ? n giiy Dieu tra xac dinh d nhiem vi khuan la trudc khi khdi phat chiem t\ Ic cao hon han so trong nude
voi nhirng thuc phiim khac. Trong tdng si > 97
Bang 2a. Ket qua xet nghiem mau mr&c cac loai tai 6 djch trong 15 ngay dau ciia cac dc4 djch
Loai mau Sd lircmg Ket qua
dircrng tinh * Tyle duvng tinh (%) Nude sinh hoat
(nude may, nude gidng, nude be) 68 0 0 00
Nude be mat
(nudcao, ho, kenh, muong, song) 86 1 1.16
Nude thai cac loai 37 1 2.70
Tdng 191 2 1.05
(*) ihrono linh vui Vibrio cholerae nhom ()1
Tap chi Y hoc dir phong. Tap XX. so 6 (l 141
Trong 15 ngay dau cua cac dot djch.
da thu thap duoc tong so 191 mau nude cac loai tai 6 djch. trong do co 68 mau nude sinh hoat (nude may: 28: nude gieng: I 8; nude be:
22), 86 mau nude be mat (nude ao. hd: 33:
nude kenh. muong: 28: nude sdng: 25) va 37 mau nude thai cac loai. Ket qua xet nghiem cho thay tat ca 68 mau nude sinh hoat thu thap duoc deu am tinh vdi vi khuan ta. Chi phat
hien 01 mau duong tinh vdi Vibrio cholerae trong sd 86 mau nude be mat va 01 man duong tinh trong tdng sd 37 mau nude thai cac loai (bang 2a). Hai mau duong tinh nay bao gdm:
01 mau nude ao va 01 mau nude cdng thai tai nha mot benh nhan. day la noi gia dinh benh nhan da dd va rlra bd phan ciia benh nhan chi trong vdng 24 gid trudc khi lay mau.
Bang 2b. Ket qua xet nghiem theo doi mau nirdc dinh ky tai mot sd trong diem djch, 4/2008 -3/2009
Thang / 2008 Thang / 2009 Ket qua
Loai mau Tong
4 5 6 7 8 9 10 11 12 1 2 3 ( + )
Nude sinh hoat
(nude may, nude 20 20 20 20 20 20 20 20 20 20 20 20 240 0 gieng, nude be)
Nirdc be mat (nude ao, ho,
40 40 40 40 40 40 40 40 40 40 40 40 480 kenh, muong,
song)
Nirdcthai 15 15 15 15 15 15 15 15 15 15 15 15 180 0 Tong sd 75 75 75 75 75 75 75 75 75 75 75 75 900 0 (*) throng linh vdi I ihrio cholerae
"Tir thang 4/2008 den thang 3/2009 cluing tdi dit thu thap va tien hanh xet nghiem tdng sd 900 man nude cac loai (djnh k\ hang thang tai
15 diem nghien ciru thudc dja ban 4 tinh 1 lii Ndi. Ha l ay ciu "Thai Binh \;i Hai Phong) bao gdm: 240 mini nude sinh hoat (nude may : 123:
nude gieng: 55; nude be: 62). 480 man nude
be mat (nude ao. hd: 252; nude kenh muong:
110; nude sdng: 118) va 180 mau nude thai cac loai. Ket qua xet nghiem cho thay tat ca 900 mau nude ciic loai qua theo ddi djnh ky deu am tinh vdi phay khuan ta (bang 2b).
Dieu tra xiic djnh d nhiem vi khuan ta tren rau thom/rau sdng
l ap chi V hoc du phong. Tap XX. so 6(114) 39
Bang 3. Kit qua xet nghiem mlu rau therm, rau song trong vu djch, 2007 - 2009 Loai mau S6 lupng Kit qua duong tinh * Ty le duong tinh (%) Lay mlu tai cac cua hang co lien quan dich te trong vu dich
La mo 8 0 0
Cac rau song khac 104 2 7.92 Tong 112 2 1,79
Lly mlu tai cac cho> dlu mdi, trang trai viing chuyen canh rau va theo ddi djnh ki 12 thang tai mpt so cho1 trong viing djch
La mo 139 0 Cac rau sdng khac 1801 0
Tong 1940 0
(*) duong linh vdi Vibrio cholerae nhdm ()I Trong \ ii dich da thu thap dupe tdng sd
I 12 mau rau therm, rau sdng cac loai tai 27 ciia hang quan an cd lien quan den cac benh nhan ta. bao gdm: 8 mau la mo. 31 mau rau ngd. 27 mau ran hting. 25 mau rau mui tan va 21 man rau cac loai khac (thi la, hanh. kinh gieii ). Ket qua xet nghiem cho thay 2/1 12 man (1.7i)"„) r a i| duong tinh voi \ i khuan ta bao gdm 1 mau ran ngd va 1 mau ran hung.
t a 2 mau rau thorn nay dupe lay tai 2 ciia hang thjt chd ma trong dd cung cd cac mlu thjt chd duong tinh vdi ta (01 mail rau ngd tai cua hang thjt chd clip" ede "Tan Mai. 11a Ndi ia 01 mau rau hiing tai cua hang thjt chd clip K92. Khuong "Trung. Ha Ndi). Tat ca cac mau ran khac deu am tinh \a khdng phat hien
0 0 0
dupe mau ran thorn ran sdng nao duong tinh o cac loai ciia hang an uong khac (ciia hang bun ngan, long Ion. biin dau. bun dc ...).
Ngoai ra. chiing tdi ciing tien hanh thu thap cac man rau tai cac clip dau mdi. viing chuyen canh rau trang trai rau va theo doi lay mau ran djnh ky tai mpt sd clip thupc dia ban 4 tinh (Ha Npi. Ha l ay cu. I lai Duong \;i Hai Phong) trong vdng 12 thang. l ong cdng 1940 mau rau thom/rau sdng cac loai da dupe thu thap lam xet nghiem tim vi khuan tii. Ket qua: tat ca 1940 mau rau thom/rau sdng cac loai deu am tinh \ di phay khuan ta (bang 3).
Cac dieu tra xac djnh d nhiem vi khuan ta trong mam torn.
40 Tap chi Y hpc dir phong. Tap X.Y. so 6 (1 I4i
Bang 4. Ket qua xet nghiem mot s6 mlu mlm torn trong vu djch nam 2007 - 2009 Dja dilm lay mau S6 lirgng Dircrng tinh (+) Ti le duong tinh
Cua hang, quan an 35 0 0
Cher dau mdi, ca sa san xuat 66 0 0
Tong so 111 0 0
l ong so 11 I mau mam torn tai cac cua hang (quan an), cho dau moi va cac co1 so san xuat duoc thu thap va lam xet nghiem. Ket qua cho thay tat ca cac mau mam torn thu thap duoc
Bang 5. Ket qua xet nghiem cac
deu am tinh voi phay khuan ta (bang 4).
Cac dieu tra xac djnh 6 nhiem vi khuan ta tren cho va thjt cho
mlu benh phim tir cho va thjt cho
So mau Dirong tinh
Loai mau So mau , , Ty le dircrng tinh (%) voi phay khuan ta*
Thit cho chin 46 2 4,35 Thit cho sing 44 5 11,36
Phan cho (ngoay hau mdn) 240 4 1,67 Tong so 330 11 3,33
I*) c/mmg linh vai Vibrio cholerae nhom Ol Trong vu djch da dieu tra va thu thap duoc 90 mau thjt cho bao gom 46 mau thjt cho song, 44 mau thjt cho chin tai mot so cira hang.
quan an. co so giet mo. co' sir nuoi nhdt cho.
Ket qua xet nghiem cho thay 7/90 (7.8%) mau thjt cho duong tinh voi Vibrio cholerae nhom Ol. Dac biet. da phat hien duoc 4.240 (1.67%) mau phan chi) lay qua tam bong ngoay hau mdn tai mot sd co sd giet md. co sd nudi nhdt, phim phoi chd lam thuc pham cung duong tinh vdi Vibrio cholerae nhdm (II (bang 5).
IV. HAN 1.1 AN
Theo kinh dien. nude duoc coi la chiec xe van chuyen quan trong nhat ciia sir lay
truyen benh ta. Trong sd 7 vu dai djch ta duoc ghi nhan trong Ijch sir the gidi, thi cd tdi 6 vu djch la do ngudn nude bj d nhiem phay khuan ta [4]. 'Tii nam 1854, nhung nghien cuu cua John Snow da khang djnh vai trd quan trong cua nude ddi vdi sir lan Iruycn djch ta [5]. Til dd den nay. da cd rat nhieu nghien ciru khang djnh them dieu nay |6.7|. Cac vu djch ta tai mien Bac nam 2007 - 2009 mang tinh chat tan phat. khdng tim thay dau hieu ve mdi lien quan cua vu djch den cac ngudn nude. Tuy nhien.
trong qua trinh dieu tra. xac minh ngudn gdc vu dich. chiing tdi van khdng loai tru gia thiet ngudn nude bj d nhiem la ngudn gdc cua vu djch. Nhirng no lire ciia chiing tdi nham xac minh sir d nhiem vi khuan ta trong cac loai 'Tap chi Y hoc dir phong. Tap XX. so 6(114) 41
nguon nude duoc tap trung vao 15 ngay dau cua cac dot dich. Day la giai doan vd cung quan trong trong dieu tra djch tc hoc ciia dich ta de xac dinh ngudn gdc cd the ciia vu dich.
Den giai doan khi dich da biing phat manh.
\ i khuan ta theo phan ngudi benh dao thai ra ngoai se gay 6 nhiem nude, dat va mdi trudng xung quanh nen viec dieu tra d giai doan sau se khdng con phan anh chinh xac ngudn lay ban dau nua. Trong giai doan 15 ngay dau ciia cac dot dich, vdi 191 mau nude cac loai duoc thu thap bao gdm 68 man nude sinh hoat. 86 mau nude be mat. 37 man nude thai tai nha benh nhan va khu \ ire d dich den cho ket qua am tinh vdi vi khuan ta. Chi duy duy nhat phat hien 1 mini nude ao va 1 mau nude cdng thai cua 1 gia dinh benh nhan cd ket qua duong tinh. nude be sinh hoat ciia gia dinh nay am tinh. Tuy nhien. qua khai thac thdng tin tir gia dinh cho thay ngudi nha benh nhan da ctd bd phan ciia benh nhan ra cdng va ra ao chi I ngay trudc khi lay mau. vi vay ciing riil de hieu tai sao 2 man nude lay tai day lai duong tinh vdi phay khuan ta Ben canh dd. qua theo ddi djnh ky cac mini nude tai cac khu vuc d dich trong
\ong 12 thang voi 900 mini cac loai da duoc xet nghiem cho thay tat ca cac man nay deu am tinh voi phay khuan ta. Nhu vay nhieu kha nang nude khdng phai la ngudn lay nhiem ban dau cua \ u dich nay.
Cac dot djch ta tai mien Bac nam 2007 - 2009 cd nhirng dac diem goi y ciia moi vu dich cd lien quan den thuc pham bi d nhiem. Ret qua nghien ciru ca benh. chiim ca benh trong giai doan dau cua cac vu dich da cho thay ty le riit cao cac benh nhan an cac loai thuc phiim nghi ngd nhu: thjt chd. iruim torn, rau thorn \a rau sdng. Ket qua nghien ciru benh cluing ciing cho thay thjt chd. la mo. ticl canh la nhiing yen td lam tang nguy co mac ta trong
\u djch. Dua vao cac ket qua dieu tra djch tl ban dim cd duoc cluing tdi da dat Ta gia thuy et
\ e ngudn gdc cua vu djch cd the la: ngudn ran
thorn, rau sdng. mam torn hoac ngudn thjt chd bj d nhiem.
Trudc het. \ e rau thorn, ran sdng. day la loai thuc pham an kem rat phd bien tai Vict Nam. dirge sir dung hang ngay trong cac bfra an. Tuy nhien vdi tap quan canh lac cua ngudi dim hien nay. cac loai rau ndi cluing va ran song, rau thorn ndi rieng rat de bj nhiem vi khuan dudng rupt neu cac viing chuyen canh ran cd sir dung ngudn nude bi d nhiem. Dac biet nguy hiem la nip quan sir dung phan tuoi trong tudi bdn ran cang lam tang nguy co ran bj nhiem khuan. trong ctd cd vi khuan ta. Ngon ra cac loai ran thorn, rau song ciing de dang bi nhiem khuan neu ngudn nude lira ran. nude sinh hoat hang ngay bj d nhiem. C"ac loai rau thorn, rau sdng la nhiing loai ran an song nen neu bj nhiem khuan thi rat de trd thanh ngudn Iruycn benh. De xac minh gia thuycT ngudn rau thom/rau sdng bj d nhiem, chiing tdi tien hanh dieu tra va lay man ran thorn, ran sdng tai cac cua hang, chg dau mdi. viing chuyen canh rau cd lien quan den cac benh nhan tir Ket qua xet nghiem hon 2.000 man ran thorn,' ran sdng/la mo tai cac cua hang quan an, mot sd cho trong theo ddi djnh ki deu khdng phat hien dirge phay khuan ta o bat ky man benh phiim nao. Chi duy nhat phat hien duoc 2 man rau sdng gdm I mau rau ngd, va mot mau ran hung duong tinh vdi phay khuan ta trong 2 dot djch khac nhau (dot 1 va dgl II) va mot dieu triing hop la ca 2 mau niiy deu duoc thu thap tai cac cira hang thjt chd ma trong do ddng thdi cung phat hien duoc mau thjt chd duong tinh vdi phay khuan ta va dieu nay khdng loai tru khii nang rau thom/rau sdng ban kem thjt cho bj d nhiem tu thjt chd sang. Nhu vay kha nang ran thom/rau sdng bj d nhiem vdi vi khuan la giiy vu dich la khdng cd co' sir.
Ket qua dieu tra djch te ca benh va nghien ciiu benh chung cho thay main torn cd the la mot yen to cd lien quan. Vdi liip quiin an uong ciia ngudi mien Bac. mam torn xuiu 42 Tap chi Y hoc dir phong. Tap XX. so 6 il 14 j
hien kha pho bien trong cac bua an gia dinh ciing nhu cac bua c6 dong nguon. Nhirng mam lorn thuong khong phai la mdn an chinh ma thuong duoc sir dung kem vai nhieu loai thuc pham dac biet khac nhu thit cho. bun. long loo
\.v... Trong nghien cuu nay. cluing toi cung da tien hanh thu thap tren 100 mau mam torn tir cac cua hang'qilan an co lien quan ciing nhu mot so co' so' san xuat. tuy nhien tat ca cac mau mam lorn duoc xet nghiem deu am tinh vdi vi khuan ta. Nhu chimg ta deu biet mam torn la mot loai thiic an co ham luong muoi rat cao co the len den 20% nen rat kho de cho vi khuan ta co the ton tai va phat trien trong moi trudng nay. Do do. gia thuyet ve vice mam torn bi d nhiem vi khuan ta lit ngudn lay nhiem trong vu dich cung da duoc loai tru.
Thit chd lii mot loai thuc pham rat phd bien va duoc ua chuong o Vict Nam. va dac biet la o mien Bac. Tir trudc den nay. y van the gidi chua he ghi nhan vu dich ta nao cd lion quan den loai thirc an dac biet nay. Tuy nhien.
trong nhiing vu dich ta biing phat tai mien Bac nam 2007 - 2009. nhieu yeu to dich te thu thiip duoc cho thay thit chd bi d nhiem cd the ddng mot vai trd quan irong. Ket qua nghien ciru ca bcnh'chiun ca benh trong giai doan dau cac dot dich nam 2007 - 2009 tai mien Bac da chi ra rang ty le benh nhan cd tien sir an thit chd trong vdng 5 ngay trudc khi mac benh rat cao (tren 50%). Trong qua trinh dieu tra ca benh/
chiim ca benh chimg tdi da phat hien duoc mot so man thit chd (ca sdng \ ;i chin) tai cac cua hang .•quan an co lien quan true tiep den ca benh duong linh vdi phay khuan ta. ket qua dieu Ira cat ngang 30 ciia hang thit chd lai Ha Ndi trong vu dich ciing phat hien 2 man thjt chd duong tinh vdi phay khuan ta d 2 cua hang khac nhau trong khi tin ca cac loai mini benh phiim khac thu thap duoc trong cudc dieu tra nay deu am tinh. Cac biing chiing ve thii chd bi d nhiem ciing duoc cung cd khi kin qua nghien ciru dieu tra cat ngang tai -I co so giet md chd
d Duong Ndi. I la Ddng cho thay rat nhieu loai benh pham thu thap duoc 0 clay duong tinh Vdi vi khuan ta trong dd nhieu nhat la thjt chd.
Tuy nhien. nguy en nhan do ngudn nude gay d nhiem thjt chd da duoc loai tru. do ket qua xet nghiem tat ca cac man nude ngudn tai nhung co sd nay deu am tinh vdi I.'cholerae. Nguyen nhan thjt chd bj 6 nhiem o mot so mini benh pham cd the do mot sd it chd sdng trong mot giai doan nao dd mang vi khuan la: cd the la mang co hpc do bj nhiem o long chd. mom \;i chan chd trong qua trinh tim kiem thirc an va an phan ngudi: cung co the chd mang sinh hoc trong rupt cua mpt so con chd. tir dd qua phan d nhiem ra mdi trudng xung quanh chd giet md trong qua trinh linn long chd idi nhiem sang nude, dung cu. mat sim va thjt chd sdng
\;i gia thiet ntiv ciing tro nen rd rang hon khi cluing tdi phat hien idi 4 mau phan chd lay qua tam bong ngoay luu; mdn duong tinh vdi phay khuan tii. Lien quan den kha nang chd mang \ i khuan ta. da cd mpt loat 5 nghien ciru thirc nghiem ciia Sack R.B va cdng sir dupe tien hanh tren chd trong nhirng nam tir 1966
1969. Ket qua nghien ciru thuc nghiem da chi ra rang chd la md hinh giiy nhiem ta phu hop va chd cd the bj nhiem vi khuan ta. mac benh lam sang dien hinh va cd dap irng mien djch gidng nhu d ngudi [9. 10.1 1.12|. Nghien ciru thuc nghiem tai Vien Ve sinh Dich tc Trung uong nam 2009 cung cho thay chd bj nhiem vi khuan ta. dao thai vi khuan ta qua phan. mac benh lam siing dien hinh khi dupe giiy nhiem bang I Cholerae nhdm Ol (ket qua nghien ciiu cua Vien VSDTTW ).
V. KET LUAN
Khdng phat hien dupe sir d nhiem vi khuan ta o cac ngudn nude an uong. sinh hoat tai khu \ uc d djch trong giai doan 2 tuan dau cua djch.
khdng phat hien dupe su 6 nhiem vi khuan ta trong la mo. ran thorn rau sdng tai Tap chi V hpc du phong. Tap XX. sd 6(114) 43
cac chg dau moi. lai vudn rau viing chuyen canh rau.
Khdng phat hien duoc su 6 nhiem vi khuan ta trong cac man mam torn trong vu dich.
Phat hien vi khuan ta nhdm Ol. tip huyet thanh Ogawa trong mot sd mau thit chd sdng. thit chd chin lai quan an. ciia hang, cho.
co' sd giet md chd cd lien quan dich te den ca benh.
Phat hien vi khuan ta nhdm Ol. tip huyet thanh Ogawa trong tam bong ngoay hau mdn mot sd chd lai co so giet md. noi nudi nhdt phan phoi chd lam thuc pham.
Nhu vay. nhieu kha nang mdi sd chd bi nhiem vi khuan ta duoc sit dung lam thuc phiim lii ngudn gdc biing phat vu djch ta tai mien Bac. Viet Nam nam 2007 va thdi gian dau ciia cac dot dich tiep theo.
TAI LII I I MAM KHAO
1. Bd V te. Quy trinh xir ly dich la. Ban hanh theo quyet djnh sd 4223'()D-BYT. cua Bd Huong Bd Y te. ngay 03 thang 11 nam 2007.. 2007.
2. W HO. Weekly epidemiological record 1st August :t)t)S. 2008. 83rd y ear, NO 3 1.
2008. 83. 269-284. htlp://w wu.who.inl/
wcr'I()08 uer833l.pdf.
3. WHO. Weekly epidemiological record.
2009. July 2009. 84th year No. 3 1, 2009. 84, 309 - 324. Tiltp:/' www.who.int/wci72009 4. Phiing Dac Cam. \ ihrio Cholera va benh
dich ta. 2003. Ha Ndi: Nha xuat ban y hoc.
5. Nguyen Tang Am. Diing Dire Trach va Nguyen Duy Thanh. Benh la El-tor Dich le hoe vd 1dm sdng. 1983. Ha Ndi: Nha xual ban Y hoc.
6. Swcrdlow. D.l... et al.. Waterborne trans- mission of epidemic cholera in Trujilla.
Peru: lessons for a continent at risk. Lan- cet. 1992. 340(8810): p. 28-33.
7. Bhattacharya. S.K.. et al., Vibrio, cholerae ()139 in Calcutta. Arch Dis Child, 1994.
71(2): p. 161-2.
8. Sack. R.B.. et al. Experimental cholera. A canine model. Lancet. 1966. 2(7456): p.
206-7.
9. Sack. R.B. and CO Carpenter. Experi- mental canine cholera. 1. Development of the model. J Infect Dis. 1969. 119(2): p.
138-49
10.Sack. R.B. and C.C. Carpenter. Experimen- tal canine cholera. IE Production by cell- Tree culture filtrates of Vibrio cholerae. J Infect Dis, 1969. 119(2): p. 150-7.
II.Sack. R.B. and C.C. Carpenter. Experi- mental canine cholera. 3. Serologic studies and rc-challcngc experiments. J Infect Dis.
1969. 1 19(2): p. 158-64.
12.Sack. R.B.. et al. Experimental canine cho- lera. IV. The chronic carrier state for Vi- brio cholerae. J Infect Dis. 1969. 1 19(2): p.
165-71.
44 Tap chi Y hoc dir phong. Tap XX. so 6 i 1 141
DENTIFICATION OF ORIGIN SOURCE OF CHOLERA OUTBREAK IN THE NORTH, VIETNAM, 2007 - 2009
Iran Nhu Duong, Ngo Huy Tu, Nguyen Thi Binh Minh. Nguyen Tran Hien Sutiimal Institute of hygiene ami Epidemiology, Hanoi
Cholera is caused by Vibrio cholera bacteria, group Ol or 0139. The disease is transmitted by consuming water or food con- tamminated with the pathogen. "There was a huge 4-wavc epidemic of cholera occurred in the North of Vietnam from October. 2007 to July. 2009. resulting in around 8000 cases and
I death. With the application of cross-section- al study method, the research aimed to iden- tify the possible source of the outbreak. The result showed that during the first 15 days of outbreaks, there were 59.8% patients report- ing that they had consumed dog meat. 54.6%
and 58.8% had eaten shrimp paste and raw vegetable during 5 days before the onset of disease, respectively. There was no evidence to show that drinking and running water were polluted with the pathogen in the first 2 weeks of outbreaks. None of 1940 raw vegetable
samples collected in wholesale- markets nor 101 shrimp paste samples collected in out- break areas were positive w ith cholera bacte- ria. However, 7/09 samples of cither raw dog meat or cooked dog meat collected from dog restaurants, markets, slaughter houses in epi- demical areas were positive w ith Vibrio chol- era bacteria, group Ol. Ogawa. There were 4/240 rectal sw abs of some dogs at slaughter houses also found positive w ith Vibrio cholera bacteria, group Ol. Ogawa. Thus, there was a great potential that cholera infected dogs which was used for food may be the origin source of cholera outbreak in the North of Vietnam. 2007 2009.
Key words: Cholera outbreak, chol- era bacteria, water, raw vegetable, dog meat.
shrimp sauce.
Tap chi Y hoe du phong. Tap XX. so 6(114) 45