Risk factors for human infection with avian influenza A H5N1, Vietnam, 2004.
To evaluate risk factors for human infection with influenza A subtype H5N1, we performed a matched case-control study in Vietnam. We enrolled 28 case-patients who had laboratory-confirmed H5N1 infection during 2004 and 106 age-, sex-, and location-matched control-respondents. Data were analyzed by matched-pair analysis and multivariate conditional logistic regression. Factors that were independently associated with H5N1 infection were preparing sick or dead poultry for consumption < or =7 days before illness onset (matched odds ratio [OR] 8.99, 95% confidence interval [CI] 0.98-81.99, p = 0.05), having sick or dead poultry in the household < or =7 days before illness onset (matched OR 4.94, 95% CI 1.21-20.20, p = 0.03), and lack of an indoor water source (matched OR 6.46, 95% CI 1.20-34.81, p = 0.03). Factors not significantly associated with infection were raising healthy poultry, preparing healthy poultry for consumption, and exposure to persons with an acute respiratory illness.
Dinh
Pham Ngoc
PN
National Institute of Hygiene and Epidemiology, Hanoi, Vietnam. peter.horby@gmail.com
Long
Hoang Thuy
HT
Tien
Nguyen Thi Kim
NT
Hien
Nguyen Tran
NT
Mai
Le Thi Quynh
le TQ
Phong
Le Hong
le H
Tuan
Le Van
le V
Van Tan
Hoang
H
Nguyen
Nguyen Binh
NB
Van Tu
Phan
P
Phuong
Nguyen Thi Minh
NT
D000293:Adolescent; D000328:Adult; D000818:Animals; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D053124:Influenza A Virus, H5N1 Subtype / Q000254:growth & development*; D007251:Influenza, Human / Q000453:epidemiology / Q000635:transmission / Q000821:virology*; D016015:Logistic Models; D008297:Male; D011200:Poultry; D011201:Poultry Diseases / Q000821:virology; D012307:Risk Factors; D011795:Surveys and Questionnaires; D014744:Vietnam / Q000453:epidemiology; D015047:Zoonoses / Q000635:transmission / Q000821:virology