title: Risk for highly pathogenic avian influenza H5N1 virus infection in chickens in small-scale commercial farms, in a high-risk area, Bangladesh, 2008.
abstract: Small-scale commercial chicken farms (FAO-defined system 3) with poor biosecurity predominate in developing countries including Bangladesh. By enroling fifteen highly pathogenic avian influenza (HPAI) cases occurring in such farms - (February - April 2008) and 45 control farms (March-May 2008) with similar set up, we conducted a case-control study to evaluate the risk factors associated with HPAI H5N1 virus infections in chickens reared in small-scale commercial farms in a spatially high-risk area in Bangladesh. Data collected by a questionnaire from the selected farms were analysed by univariable analysis and multivariable conditional logistic regression. The risk factors independently associated were 'dead crow seen at or near farm' [odds ratio (OR) 47.4, 95% confidence interval (CI) 4.7-480.3, P = 0.001], 'exchanging eggtrays with market vendors' (OR 20.4, 95% CI 1.9-225.5, P = 0.014) and 'mortality seen in backyard chicken reared nearby' (OR 19.4, 95% CI 2.8-131.9, P = 0.002). These observations suggest that improved biosecurity might reduce the occurrence of HPAI outbreaks in small-scale commercial farms in Bangladesh.
authors.affiliation: Department of Microbiology, Chittagong Veterinary and Animal Sciences University, Khulshi, Bangladesh. biswaspk2000@yahoo.com
authors.forename: P K
authors.initials: PK
authors.lastname: Biswas
authors.forename: M H
authors.initials: MH
authors.lastname: Rahman
authors.forename: A
authors.initials: A
authors.lastname: Das
authors.forename: S S U
authors.initials: SS
authors.lastname: Ahmed
authors.forename: M
authors.initials: M
authors.lastname: Giasuddin
authors.forename: J P
authors.initials: JP
authors.lastname: Christensen
mesh_terms: D000383:Agriculture; D000818:Animals; D001459:Bangladesh / Q000453:epidemiology; D002645:Chickens; D053124:Influenza A Virus, H5N1 Subtype; D005585:Influenza in Birds / Q000453:epidemiology / Q000821:virology*; D016017:Odds Ratio; D012307:Risk Factors