Rapid antigen detection in the diagnosis of highly pathogenic avian influenza (H5N1) virus in Nigeria

Highly pathogenic avian influenza (AI) is an infectious disease of agroeconomic and public health importance. The outbreak that occurred in Nigeria (2006–2008) was devastating to the poultry industry and raised public health concerns. In the course of its control, rapid laboratory confirmation of suspected cases in poultry was essential for prompt mobilization of control logistics for depopulation and decontamination of affected premises. Commercial rapid test kit was evaluated in the diagnosis of highly pathogenic AI (HPAI) as a preliminary to virus isolation. Between 2006 and 2007, 382 cases were tested out of which 149 were positive by rapid antigen detection. Virus isolation yielded 171 positive cases. The relative diagnostic sensitivity of Anigen Rapid AIV Ag test was 84.3% (95% confidence interval [CI], 78.1–88.9%), whereas the relative diagnostic specificity was 97.7% (95% CI, 94.2–99.1%). Rapid antigen detection is a useful technique for prompt diagnosis of HPAI for early detection and containment.