Comparison of serological assays for detecting antibodies in ducks exposed to H5 subtype avian influenza virus

BMC Veterinary Research

Research Article

Sue Lowther¹  John Bingham¹  Hendra Wibawa²  Dessie Eri Waluyati³  Tri Bhakti Usman³  Akhmad Junaidi⁴  Joanne Meers⁵  Joerg Henning⁵ 

[1] CSIRO-Australian Animal Health Laboratory, Geelong, VIC, Australia;CSIRO-Australian Animal Health Laboratory, Geelong, VIC, Australia;School of Veterinary Science, The University of Queensland, Gatton Campus, Gatton, QLD, Australia;Disease Investigation Centre Wates, Yogyakarta, Indonesia;Disease Investigation Centre Wates, Yogyakarta, Indonesia;Disease Investigation Centre Wates, Yogyakarta, Indonesia;Directorate General of Livestock and Animal Health Services, Ministry of Agriculture, Jakarta, Indonesia;School of Veterinary Science, The University of Queensland, Gatton Campus, Gatton, QLD, Australia;

关键词: Avian influenza;    H5N1;    Hemagglutination inhibition test;    Virus neutralization test;    Horse red blood cells;    Duck;    Kappa;   

DOI  :  10.1186/1746-6148-8-117

 received in 2012-04-05, accepted in 2012-06-29,  发布年份 2012

来源: Springer

【 摘 要 】

BackgroundChicken red blood cells (RBCs) are commonly used in hemagglutination inhibition (HI) tests to measure hemagglutinating antibodies against influenza viruses. The use of horse RBCs in the HI test can reportedly increase its sensitivity when testing human sera for avian influenza antibodies. This study aims to compare the proportion of positives detected and the agreement between two HI tests using either chicken or horse red blood cells for antibody detection in sera of ducks experimentally infected or naturally exposed to Indonesian H5 subtype avian influenza virus. In addition, comparison with a virus neutralisation (VN) test was conducted with the experimental sera.ResultsIn the experimental study, the proportion of HI antibody-positive ducks increased slightly, from 0.57 when using chicken RBCs to 0.60 when using horse RBCs. The HI tests indicated almost perfect agreement (kappa = 0.86) when results were dichotomised (titre ≥ 4 log2), and substantial agreement (weighted kappa = 0.80) for log titres. Overall agreements between the two HI tests were greater than between either of the HI tests and the VN test. The use of horse RBCs also identified a higher proportion of antibody positives in field duck sera (0.08, compared to chicken RBCs 0.02), with also almost perfect agreements for dichotomized results (Prevalence and bias adjusted Kappa (PABAK) = 0.88) and for log titres (weighted PABAK = 0.93), respectively. Factors that might explain observed differences in the proportion of antibody-positive ducks and in the agreements between HI tests are discussed.ConclusionIn conclusion, we identified a good agreement between HI tests. However, when horse RBCs were used, a higher proportion of sera was positive (titre ≥ 4 log2) than using chicken RBCs, especially during the early response against H5N1 virus. The HRBC-HI might be more responsive in identifying early H5N1 HPAI serological response and could be a recommended assay for avian influenza sero-surveillance in both wild and domestic birds.

【 授权许可】

Unknown   
© Wibawa et al.; licensee BioMed Central Ltd. 2012. This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.