KHA NANG CANH TRANH GIAO PHOI CUA CHUNG MUOI AEDES AEGYPTI OX513A VOI CHUNG Jlf NHIEN THU THAP O OAO CAT HAl, HAI PHONG
Tran Vu Phong, Nguyen Thuy Hoa, Nguyen Thi Yen, TrSn Hai Son, Nguyen Tran Hien, Tr5n Nhu Duong, Nguyfin Hoang Le, Vu Sinh Nam*, Richard Adrey4*.
Men Ve sinh dich te Trung inrng, Hd Xdi;
* Cue Y te dir phdng I let is tun;
** OXITEC - Trudng Dili hoe Oxford, Anh
TOM TAT
Chung mudi Ae. aegypti mang gen gay chet mudn 0X513A duoc nhan nudi trong phdng thi nghiem va duoc xac dinh kha nang canh tranh giao phdi vdi chiing tu nhien tai Vien Ve sinh dich ti Trung ucrng de thu
nghiem phuong phap phdng chdng mudi vec to truyen benh sot xuat huyet bang canh tranh dong loai.
Ket qua, da nhan nudi thanh cdng din thi he thu 10(F10) chung Ae. aegypti 0X513A tai phdng thi nghiem cua Vien Ve sinh dich ti Trung uong, vdi dac diim vi su phat triin tir trung din mudi trudng thanh tuong tu vdi chung Ae. aegypti tu nhien thu thap tir dao Cat Hai. Sir dung 100 ca thi mudi due chung Ae. aegypti OX513A va 100 ca thi mudi due chung Ae. aegypti tu nhien cho giao phdi vdi 100 mudi cai chung Ae.
aegypti tu nhien, da xac dinh ty le giao phoi vdi mudi cai cua mudi due chung 0X513A va mudi due chung tu nhien, tuong ung la 57 % va 43 %. Dieu tra cdn triing tai 200 nha d 4 diim A, B, C va F tren dao Cat Hai da xac dinh cum A cd ty le mat dp bp gay Ae. aegypti cao nhat (28,7 con/nha) va cd cac yiu td dia ly, sinh thai phii hep hon cac diim khac di thu nghiem phdng tha chiing mudi chuyin gen gay chit mudn 0X513A di phdng chdng muoi Ae. aegypti trong nghien ciru tiip theo
Tir khoa: Aedes aegypti, vec-to, dengue, sit xuit huyet, Cat Hai.
I. DAT VAN 1)1
Virus dengue giiy benh sdt xuat huyet (SXH) duoc ghi nhan 0 nhieu chau luc tren the gidi. trong 20 nam qua. sd ca mac sdt xuat huy et (SXH) tang gap 3 lan so vdi 30 nam vc trudc. dii lam can benh truyen nhiem nay trd thanh \ an de \ te toan cau, vec-to chinh truyen benh la Aec/e.s aegypti. Cho den nay, chua cd vac-xin de phdng benh SXH nen phdng chdng vec-to truyen benh la bien phap duoc To chirc Y te the gidi va cac nha hoach dinh chien lucre y te su dung lam chien luoc chinh nham duong
dau vdi can benh toan cau niiy [1], [2].
Su dung hoa chid diet cdn triing la bien phap phong chdng mudi vec-to truyen thdng.
nhung cd the giiy anh huong den mdi trudng, nen nhirng bien phap phdng chdng vec-to bang tac nhan sinh hoc dang duoc nhieu nha khoa hoc quan tam thu' nghiem. Viec sir dung chiing (ddng) tuyet sinh la chien luoc phdng chdng cdn triing tien tien da duoc biet den vdi nhung thanh cdng duoc ghi nhan trong viec phdng tru ruoi qua Dja Trung Hai Ceratilis eapilala tren dien rdng. dieu nay da gpi md Tac gia: Tran Vu Phong
Dja chi: Vien Vc sinh djch tc Trung uong, sd 1 Yersin, Ha Ndi Dien thoai: 0913074450
Email: tranvuphong tiyahoo.com
204 Tap chi Y hpc du phdng, Tap XX. so 6(114)
mot hudng mdi cho phdng chdng vec-to SXH.
Mot so thii nghiem da duoc cac nha khoa hoc tien hanh tai An Do trong nhieu thap nien qua cho thay phuong phap nay tuy rat khd thuc hien vdi mudi nhung neu lam duoc thi rat cd nhieu trien vong bdi nhieu tinh uu viet nhu khdng gay ton hai vdi mdi trudng nhu su dung hda chat va cd tinh ben viing khi da duoc phu tren dien rdng [3|. Cd hai chien luoc can thiep den quan the mudi: (1) Thay the dan quan the tu nhien bang quan the it cd nguy ca gay hai (cluing khdng the lam lay truyen virus gay benh) bang each tac dong den khu he sinh vat va he gen trong tu nhien. (3) Lam giam quan the tu nhien bang chung mang gen gay chet khdng gay anh huong den khu he sinh vat dia phuong v i khdng thiet lap chiing sinh vat mdi.
Chinh vi vay. chien luoc thu hai cd the se duoc lira chon de phdng chdng SXH tai Viet Nam trong tuong lai. neu qua nghien ciiu thuc nghiem cluing minh duoc nhiing uu diem
cua phuong phap mdi nay. De tai nghien ciiu duoc thuc hien nham muc tieu: (I) Danh gia kha nang canh tranh giao phdi va cac dac diem sinh hoc cua ddng mudi chuy en gen so sanh v d i ddng Ae. aegypti tir nhien thu thap tu dao Cat Hai: (2) Khao sat thanh phan loai. mat do quan the mudi va cac dieu kien sinh thai de chon dja diem cho thu nghiem phuong phap phdng chdng SXH mdi tai dao Cat Hai, Hai Phdng.
II. PIIU/ONG PHAP NGHIEN CUU 2.1. Vat lieu
Dia diem thuc hien: Cac thuc nghiem nhan nudi, so sanh kha nang canh tranh giao phdi duoc tien hanh tai Phdng thi nghiem cdn triing, dam bao an toan sinh hoc cap do 2 tai Vien Ve sinh djch te Trung uong. Nghien ciiu danh gia phan bd. mat do quan the mudi Aedes va chiing loai d bo gay ngudn thuc hien tai bdn diem A. B. C vii 1 tren dao Cat Hai thanh phd Hai Phdng vao thang 4/20 10.
Hinh 1. Vj tri cac diem dieu tra quan the Aedes tai dao Cat Hai
Tap chi V hoc du phdng. Tap XX. so 6 (I 14) 205
Ddi tirong nghien ciru: Cluing Ae. ae- gypti OX5 13A co nguon gdc tir Dong Nam A cua cong ty OXITEC duoc nhap khau tir Ma- lay sia \ ao Viet Nam vdi sy dong y ciia Bo Y te de sir dung cho nghien ciru. Chung Ae.aegypti tu nhien duoc phat trien tir bp giiy thu thap tai dao Cat Hai. Hai Phong.
2.2 Phuong phap:
Nhan nuoi giir cluing. Muoi Aedes aegypti dong OX513A dupe nhan nupi giir chimg theo phuong phap chuan ciia OX PEC trong dieu kien phong thi nghiem (nhiet dp 27"C ± 1; dp am 80%; sang : tdi 12:12 gid).
Mudi cai sau khi giao phdi se dupe hut mau chupt va cho de trung de chuyen tiep the he sau. Trung dupe chp nd va bp gay dupe nudi vdi tac nhan dac biet (Tetracycline) kim ham gen gity chet mudn de bp giiy cd the phat trien va trudng thanh binh thudng. Cac dac diem sinh hpc va qua trinh phat trien dupe ghi nhan thep tirng the he. Mudi thu thap tir Cat Hai cung dupe nudi trong dieu kien tuong tu tai Vien Ve sinh dich te Trung uong.
77n/' nghiem khd ndng canh tranh giao phdi: Thu nghiem nay dupe thiet ke theo phuong phap chuan cua OXITEC da dupe thu nghiem tai Malaysia. Mdi ca the quang dupe nudi trong mpt tuyp nhd dc no thanh mudi va xac dinh gidi tinh. Quang due ciia ca 2 ddng deu dupe do chieu rpng lung nguc de dam bap ddng deu vc kich thudc co the. Mudi tir 3 den 5 ngiiy tudi dupe sir dung cho cac thir nghiem canh tranh giao phdi. Mdi long vudng (30 x 30 x 30 cm) cd san 5 con cai ddng Cat Hai duoc tha them vao 5 con due ddng Cat Hai va 5 con due ddng OX5 1 3A de giao phdi trong 24 gid. Sau 48 gid. mudi cai dupe hut mau chupt nhat trang trong vdng 24 gid. Moi con cai da giao phdi va hut mau dupe nudi trong 1 dng
nghiem cd dat giay tham dc de triing. Tdng sd muSi cai dupe thir nghiem la 100 CPII chia lain 20 ldng va lam 2 dot 12 7 \ii 29/7. Sd lupng triing ciia tirng cpn cai dupe ghi nhan vii dupe cho nd toan bp thanh bp giiy de xac dinh cd ngudn gdc bd la ddng OX513A hay Cat Hai.
Vi ddng mudi OX513A da dupe mang gen phat huynh quang nen rat de nhan biet chiing bang nhiing ddm phat sang dpc theo dng tieu hda ciia bp gay khi quan sat bang kinh hien vi huynh quang.
Dieu tra thanh phan loai vd mat dp quan the Aedes tai dao Cat Hdi: Bdn diem giam sat dupe xac djnh tai dao Cat I lai bang ban dd Google Map va thiet bi dinh vi toan cau (GPS); Dieu tra d bp gay ngudn dupe tien hanh tai 50 nha x 4 diem dieu tra. Tai mdi nha.
cac dung cu chiia nude trong va ngoai nha deu dupe giam sat bp gay va quang thep phuong phap giam sat va thu thap mau cua Vien Ve sinh dich te trung uong. Tat ca cac mau bp giiy thu thap dupe dinh loai tai phdng thi nghiem Con triing y hpc Vien ve sinh dich te Trung uong, quang thu thap dupe cho nd thanh mudi trudng thanh de xac dinh loai; Mat dp quan the vectp dupe xac dinh bang chi sd quang/
ngudi va chi sd Bretcau.
Dieu tra bang bay triing theo phuong phap chuan cua Td chirc y te the gidi dupe tien hanh ddng thdi vdi dieu tra d bp gay ngudn tai 30 nha x 4 diem dieu tra. Tai mdi nha, 1 bay trung dupe dat trpng nha va 1 bay dupe dat ngoai nha trong vdng 7 ngay trudc khi dupe dua vc phdng thi nghiem Cdn triing y hpc Vien ve sinh dich te Trung uong de xac djnh sd lupng triing thu thap dupe. Trung se dupe cho no thanh bp gay va djnh Ipai de xiic dinh Ipai va mat dd quan the theo chi sd tning/bay.
Tap chi Y hpc du phdng. Tap XX, so 6 (1 141
III. KFT (,)l \ VA HAN I I AN
3.1. Nhan nuoi muoi trong phong thi nghiem
Bang 1. Thdi gian phat trien ciia chung Ae. aegyptj 0X513A va chung Ae. aegypti tir nhien ir dao Cat Hai nuoi trong phong thi nghiem
Chung Ae. aegypti Ty le triing nd Triing - quang Triing - muoi 0X513A
Tu nhien P
85.1%
89.2%
0,56
6 8 7.1 0,21
8.2 7.9 0,43 Chung Ae. aegypti OX513A duoc tiep nghiem. nhung khi so sanh ve thoi gian phat nhan tii1 thang 11/2009 va da nuoi chuyen tiep trien cho thay chung Ae. aegypti OX5 13A va thanh cong den the he thu 10 (F10) tai phong chung Ae. aegypti thu thap tu dao Cat Hai thi nghiem ciia Vien trudc khi su dung cho thu ciing trong dieu kien nuoi tuong dong (nhiet nghiem kha nang canh tranh giao phoi. Mac do 27"C I 2; do am 80 % ± 10 %; sang/tdi dii thoi gian phat trien tii triing den muoi phu la 12/12 gid) la khong khac biet cd y nghTa thudc rat nhieu \ao nhiet do, mat do mudi va thong kc.
luong thirc an cung cap, dieu kien phdng thi 3.2. T hii nghiem kha nang canh tranh giao phdi
Bang 2. Canh tranh giao phdi giira chiing Ae. aegypti OX513A va chiing Ae. aegypti thu thap o Cat Hai trong phdng thi nghiem
Mudi cai duoc giao phdi Triing thu duoc
Chiing Ae. aegypti So luong Ty le Tong sd Ty le Trung binh
0X513A 56 57% 3.258 56,9% 58,2 ± 18,1
Cat Hai 42 43% 2.526 43,1% 58,7 ± 15.5
Tong so 98 100 5.784
0.28 Trong long sd 100 mudi cai duoc thii'
nghiem, 98 con duoc ghi nhan la cd giao phdi.
co hai mudi cai bj chet khi chuyen sang tuyp de khdng xac djnh duoc la cd giao phdi hav khong va duoc loai khdi sd lieu phan tich.
Ket qua xiic dinh ngudn gdc bo gay bang kinh hien vi huynh quang cho th as 56 mudi cai Ae
aegypti (57 %) duoc giao phdi biii mudi due chiing OX513A va 42 mdi cai duoc giao phdi voi mudi due Cat Hai (43 %). Tuy su khac biet nay khong cd y nghTa thdng kc (P = 0.2H) nhirng cho thay kha nang canh tranh giao phoi ciia mudi due chung OX5I3A khdng kem chung mudi tu nhien cua Cat Hai.
Tap chi Y hoc du phdng. Tap XX. so 6(114) 207
Cong ty trach nhiem huu han Oxitec la moi cong ty ciia nuoc Anh chuyen phat trien cac cong nghe sinh hoc de khong che quiin the cac con triing gay hai cho nong nghiep va y tc bang cong nghe gen lam giam kha nang sinh san ciia con triing da co nhieu thanh cong trong 50 nam qua. He thong cong nghe gen niiy cua Oxitec. duoc gpi tat la R1DL. co the nhan giong muoi due bat thu Aedes aegypti de khi chiing giao phoi voi muoi cai tai dia phuong se sinh ra the he con chet 6 giai doan bp giiy cudi hoac nhdng. Viec phong tha so lupng Ion muoi due tuy ct sinh (khong hut mau nen khong co vai tro truyen benh) vao viing dich. vdi hien tupng canh tranh giao phoi voi muoi due tir nhien. se lam cho quan the muoi moi sinh ra khong co kha nang truyen benh do
bi giam thieu hoac tuyet diet. Cong nghe tuyet sinh ca the dire bang phong xa (SIT) cung dupe irng dung \;i co nhirng thanh cong vdi mpt sd Ipai con triing giiy hai [4J: Tuy nhien.
cdng nghe niiy khdng the ap dung v di mudi vi se lam cho con due giam kha nang giao phdi canh tranh trong tir nhien. nhung cdng nghe mdi ciia Oxitec da giai quyet dupe khd khan niiy. Con due duoc lam cho tuyet sinh bang cdng nghe gen nen hoan toan cd du kha nang giao phdi canh tranh trong tir nhien. Phuong phap phdng chdng nay dupe cpi la hieu qua.
chi phi hop ly va khdng doc hai: Hon nira. nd cd the phdi hop v d i ciic bien phap phdng chdng khac nhu sir dung tac nhan sinh hpc Mesoey- elops (me /d) de diet bp gay vdi su tham gia cua cong ddng.
Co phat sang huynh quang: Khdng co phat sang huynh quang:
Bp gay co bd la dong OX513A Bp gay cd bd la dong Cat Hai Hinh 1. Phat hien nguon goc bp gay Ae. aegypti bang kinh hien vi huynh quang SO lupng trirng de til mudi cai Ae. ae- Id trung cua muoi cai dupe thu tinh vdi mudi gypti thu tinh voi chung mudi due OX513 va due ciia ca 2 chung deu nd thanh bp giiy vdi chung mudi due Cat Hai khac biet khdng dang ty le nd tir 72 % den 96 % sd ti ling tha. Ty le kc(P r 0.28). Tuy su phat trien phOi va so lupng niiy la rat cao so vdi cac nghien ciiu khac ve trirng de phu thudc nhieu vao lupng mau muoi kha nang sinh san cua mudi Ae. aegypti trong cai hiu dupe, sd lupng trirng de trung binh ciia dieTi kien phdng thi nghiem. Khac vdi trong con cai dupe giao phdi boi cpn due cua chiing dieu kien tu nhien, loai muoi nay cd co che nd OX5I3 va Cat Hai rat tuong ddng nhau (58,2 triing khi ngap nude rat dac biet, sau khi da
* I8.l va 58.7 ± 15.5 trung/muoi). Tat ca cac hoan thien phdi, trirng cua cd kha nang chiu Tap chi Y hpc dy phong. Tap XX. so 6 (1 14i
kho han trong khoang 6 thang. khi ngap nude.
chi khoang 30 % so trirng nd, cdn lai chung se nd dan vao cac lan ngap nude tiep theo. Day la mot co che bao toan ndi gidng cua loai muoi nay va lam cho cdng tac phdng chdng vec-to' gap rat nhieu khd khan.
Su dung cdng nghe chuyen gen de tao chung Ae. aegypti OX513A mang gen gay chet mudn (co ngudn gdc Ddng Nam A). Vludi due da chuyen gen se duoc tha de giao phdi vdi mudi cai tren thuc dia. Con lai se khdng sdng sdt duoc cho den luc trudng thanh va vi the se dan dan lam giam quan the mudi tai dja phuong trong vdng 3 den 9 thang. Gen gay chet mudn se lam the he con lai khdng phat trien thanh mudi vdi ty le chet ciia bp giiy vii quang la 99%. Mudi sdng sdt (1%) khdng cd nhiing bien ddi vc co' the so vdi chung tu nhien vii van mang gen giiy chet mudn nen van lac dpng den ty le chet ciia the he sau. Gen giiy chet mudn LA5 13 duoc dieu khien bdi Tetracycline, vi the trong phdng thi nghiem. cluing mudi niiy cd the dupe nhan len nudi binh thudng de cd the cung cap dii sd lupng ca the due cim thiet cho thirc dja. Mudi due dachuyen gen se dupe tha de giao phdi xdi mudi cai tren thuc dia. con lai se khdng sdng sdt dupe clip den luc trudng thanh x ii \ i the se lam giam quan the mudi tai dja phuong
|5|. Ket qua nudi mudi thuc nghiem cua cluing tdi trong nghien ciru nay ciing tuong tir vdi ket qua nghien ciiu tai Malaysia xe cac dac tinh sinh hoc ciia cluing mudi mang gen giiy chet mudn \ i cluing tir nhien ciia Malaysia.
xdi sir khac biet khdng cd y nghia thdng ke xe
sd lupng trung de vii thdi lupng phat trien cua 2 ddng mudi niiy. Nhung nghien ciru ve kha nang canh tranh giao phdi trong khdng gian khoang 50 m3 tai Malay sia cung cho thiiy 52
% mudi cai ban dia giao phdi vdi mudi due chung OX513A va 48 % giao phdi vdi mudi due ban dja |6|.
Tai Hpi thao vc an toan sinh hpc chp cpn nguoi \ ii mdi trudng ddi vdi vice sir dung mudi mang gen gay chet mudn do TO chirc y te the gidi phdi hop vdi An Dp thirc hien thang 3 nam 2010 da phan tich 33 yeu td nguy co"
cd the khi phdng tha vao mdi trudng tir nhien
\ di su tham gia cua cac chuyen gia va cac nha khoa hpc qudc le ve ITnh vuc cdng nghe gen x a phdng chdng vec-to. Nhirng ket qua nghien ciiu cho den nay deu khang djnh rang khdng cd dac tinh giiy hai nao dupe dua vao bp gen ciia cluing OX513A. Mire dd di truyen gen ngang ciia chiing mudi nay ciing rat nhd bdi gen gay chet mudn khi thieu tetracycline trong mdi trudng phat trien la mpt rao can rai Idn lam cho chimg mudi nay khd cd the ton tai trong dieu kien tir nhien. Thir nghiem ve lai tao cudng ep giua chung mudi niiy vdi mudi .•le. alhopielus hoan toan khdng the tao ra con lai, cho thay rao can ve giao phdi va thu tinh giua cac loai ciing ngan khdng cho sir di truyen ngang xuat hien. Cho den nay. chua phat hien cd bat ky dau hieu nao ve cac dac tinh sinh hpc va hien tuong truyen ngang gifra cac ca the mudi Toxorhynchiles splendens dupe nudi bang bp giiy ciia chiing Ae aegypti OX513A trong cac thir nghiem cua Vien nghien cuu y hpc qudc gia Malay sia[6J.
Tap chi Y hpc du phong. Tap XX. so 6(114) 209
3.3. Dieu tra co ban \ c quan the Acdcs tai dao Cat Hai
Bang 3. Dilu tra quan the mudi Aedes tai dao Cat Hai, 6/2010 Cum dieu tra Chisd Cat Hai
A B C F
S6 nha dieu tra 200 50 50 50 50
S6 nguoi 843 232 212 200 199
Ae. aegypti
Breateau 17.0 50.0 10.0 8.0 0.0
Mat do bo gay 9 1 29.7 4.7 2 0 -
Quang/nguoi 0.5 1 4 0.1 0.2 -
Bay trirng
S6 triing trong nha 67 45 22 0 0
So trirng ngoai nha 492 413 0 79 0
Ae. albopictus
Breateau 22.0 4.0 22.0 18.0 44.0
Mat dp bp gay 0 6 0.1 0.6 0 8 0.9
Quang/nguoi 16.9 2.0 21.0 8.0 36.7
Bay trirng
S6 trirng trong nha 500 0 326 101 73
So trirng ngoai nha 895 162 347 64 322
Copepods
% Mezo (+) 5% 3% 8% 2% 5%
Ket qua dieu tra con trung tai 200 nha cho thay ca 2 loai muoi Ae. aegyli vii Ae. al- bopictus deu co mat tai dao Cat I lai voi mat do bo gay va quang/nguoi rat khac nhau giua cac diem dieu tra. loai Ae. albopictus chieTn uu the va pho bien hon Ae. aegvli. Chiing co mat 0 tat ca cac cum dieu tra voi mat do quang/
- 10 Tap chi Y hoc du pho
nguoi (16.9) cao gap 33,8 lan so voi Ae. ae- gypti (0.5). Dac biet la cum A, co vi tri tach biet voi cac khu vuc khac va nam sat bien, co mat do bo gay Ae. aegypti Ion nhat (29.7 con/
nha) tap trung chu yeu trong bi xay (88.4 %), la noi co nhieu thuan loi cho viec thii' nghiem phuong phap phong chong Ae. aegypti bang ig, Tap XX. so 6.(114)
chung OX5 13A. Phan tich 240 bay trirng thu thap tai Cat Hai cho thay ca 2 loai muoi nay deu co tap tinh de trirng ca trong va ngoai nha va Ae. alhopielus chiem uu the hon Ae. ae- gypti vdi so luong trirng de vao cac bay trirng la 1.395 va 499. Hien tupng nay cung phii hpp voi xu huong chung hien nay la.4c. albopictus dan dan thay the viing lanh tho ciia Ae. aegypti o mien Bac Viet Nam.
Copepods ton tai tu nhien voi ty le til" 3 den 8 % cac dung cu chira nude cung dupe ghi nhan tai tat ca 4 diem dieu tra tai Cat Hai cho thay tac nhan sinh hpc nay phan bo rpng rai tai cac viing sinh thai va triing lap voi 6 sinh san cua muoi Aedes fir khap mpi dia phuong trong ca nuoc; Cho thay tiem nang su dung tac nhan sinh hpc nay trpng cac chuong trinh phong chong tong hop vec to truyen benh SXH tai Viet Nam (ket qua bang 3).
VI. KET LUAN
Da nhan nuoi thanh cong the he thii 10 chung Ae aegypti OX513A trong phong thi nghiem dc cung cap cho cac nghien ciiu thir nghiem; Chung muoi chuy en gen co dac diem sinh hpc tirong dong voi chiing Ae. aegypti tu nhien ciia dao Cat I lai ve sir phat trien tir triing den muoi; Xiic djnh sir tuong dong ve kha nang canh tranh giao phoi giua muoi cai chiing Ae.
aegypti tu nhien vdi mudi due chung Ae. ae- gypti OX5 13 A va mudi due cluing Ae. aegypti tu nhien. tuong ung la 57 % va 43 %.
Ket qua dieu tra cdn triing tai 200 nha d 4 diem A. 13. C va F tren dao Cat Hai da xac djnh cum A cd ty le mat dp bp giiv Ae.
aegypti cao nhat (28,7 con/nha) so voi cac diem khac; Day la cum diem each biet so vdi cac cum diem khac. la noi ly tuong cho thu nghiem phirong phap mdi phdng chdng chii dong SXH bang ddng mudi mang gen gav che't mudn OX5 1 3A.
Liri cam an: Nghien ciiu duoc thuc hien vdi su hd mot phan kinh phi, trirng mudi chuyen gen, ky thuat tir cdng ly OXITEC thudc Truong Dai hoc Oxford; Su too dieu kien cua Bd Y te; Su hop tdc cua Trung tam y ti' du phdng Hai Phdng, Trung tam y te huyen Cat Hai vd ede can bp dia phuong de thuc hien nghien ciiu.
TAI LIEU THAM KHAO
1. Gubler D. J. (2002). Epidemic dengue/den- gue hemorrhagic fever as a public health.
social and economic problem in the 21st century. Trends Microbiol 10: 100 103.
2. Kay B. H. and Nam V. S. (2005). New strat- egy against Aedes aegypti in Vietnam. The Lancet, Vol. 365, No. 9459: 613 - 617.
3. Subbarao S. K. (2010). Review of ster- ile techniques in Indiaduring the 1960s
& 1970. Second Asian training course on biosafety for human health and the envi- ronment in relation to potential release of genetically modified vectors. Madurai. In- dia.
4. Alphey L. (2002) Re-engineering the ster- ile insect technique. Insect Biochem Moi Biol. 32: 1243 - 1247.
5. Phuc H. K., Andreasen M. IE, Burton R.
S.. Vass C, Epton M. J., Pape G.. Eu G..
Condon K. C, Scaifc S., Donnelly C. A..
Coleman P. G., White-Cooper H. and Al- phey L. (2007). Late-acting dominant le- thal genetic systems and mosquito control.
BMC Biology: 5-11.
6. Lee H. L. (2010). Comparative life history studies on wild type and transgenic Aedes aegypti (L.). Second Asian training course on biosafety for human health and the envi- ronment in relation to potential release of ge- netically modified vectors. Madurai. India.
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MATING COMPETITION BETWEEN STRAINS AEDES AEGYPTI OX513A WITH COLLECTED AEDES AEGYPTI IN CAT HAI ISLANDS
Tran Vu Phong, Nguyen Thuy Hoa, Nguyen Thi Yen, Nguyen Hai Son, Nguyen Tran Hien.
Tran Nhu Duong, Nguyen Hoang Le, Vu Sinh Nam*, and Richard Adrey**.
National Institute of Hygien anil Epidemiology, Vietnam;
"General Department of Preventive Medicine, Ministry of Health, Vietnam;
** OXITEC - Oxford University, England Ae. aegvpti strain contains late-acting
dominant lethal gene OX513A, which has been raised in laboratory in order to supply mosquitoes for the experiment to assess mat- ing competition.
The results showed that: Ae. aegypti OX513A strain is raised at Laboratory in Na- tional Institute ofllygien and Epidemiology to
If. aegypti OX5I3A FIO with the character- ization of egg growth into mosquitoes similar to collected Ae. aegypti in Cat Hai Island. Us- ing 100 Ae. aegypti OX5I3A males and 100 collected Ae. aegypti male for mating with Ae. aegypti female, the mating rate between collected Ae. aegypti female with Ae. aegypti OX5 I 3 A male and collected Ae. aegypti male
were determined to be 57 % and 43 %, respec- tively.
Entomological survey at 4 places A.
B. C and E in the Cat Hai Island with total 200 investigated houses showed the highest distribution of Ae. aegypti larval (28.7 larval/
house) at place A in comparation with other places. Especially in geographical term, place A is isolated w ith other places and new bio- logical method for dengue vector control by Ae. aegypti strain which contains late-acting dominant lethal gene OX513A in Cat Hai Hai Phong will be commenced in the next study.
Key word: Aeiles aegypti. vector, den- gue, hemorrhagic fever. Cat Hai.
212 Tap chi Y hoc du phong. Tap XX. so' 6 (1 141
