Seroprevalence survey of avian influenza A(H5N1) among live poultry market workers in northern Viet Nam, 2011
10.5365/WPSAR.2014.5.2.006
- Author:
Dung Tham Chi
;
Dinh Pham Ngoc
;
Nam Vu Sinh
;
Tan Luong Minh
;
Hang Nguyen Le Khanh
;
Thanh Le Thi
;
Mai Le Quynh
- Publication Type:Journal Article
- From:
Western Pacific Surveillance and Response
2014;5(4):21-26
- CountryWHO-WPRO
- Language:English
-
Abstract:
Objective:Highly pathogenic avian influenza A(H5N1) is endemic in poultry in Viet Nam. The country has experienced the third highest number of human infections with influenza A(H5N1) in the world. A study in Hanoi in 2001, before the epizootic that was identified in 2003, found influenza A(H5N1) specific antibodies in 4% of poultry market workers (PMWs). We conducted a seroprevalence survey to determine the seroprevalence of antibodies to influenza A(H5N1) among PMWs in Hanoi, Thaibinh and Thanhhoa provinces.Methods:We selected PMWs from five markets, interviewed them and collected blood samples. These were then tested using a horse haemagglutination inhibition assay and a microneutralization assay with all three clades of influenza A(H5N1) viruses that have circulated in Viet Nam since 2004.Results:The overall seroprevalence was 6.1% (95% confidence interval: 4.6–8.3). The highest proportion (7.2%) was found in PMWs in Hanoi, and the majority of seropositive subjects (70.3%) were slaughterers or sellers of poultry.Discussion:The continued circulation and evolution of influenza A(H5N1) requires comprehensive surveillance of both human and animal sites throughout the country with follow-up studies on PMWs to estimate the risk of avian–human transmission of influenza A(H5N1) in Viet Nam.
