Survival of Highly Pathogenic Avian Influenza H5N1 Virus in Tissues Derived from Experimentally Infected Chickens

Abstract

ABSTRACT Eurasian lineage highly pathogenic avian influenza (HPAI) H5N1 virus has been a severe threat to the poultry industry since its emergence in 1996. The carcass or tissues derived from infected birds may present the risk of the virus spreading to humans, animals, and the surrounding environment. In this study, we investigated the survival of the virus in feather, muscle, and liver tissues collected from six chickens ( Gallus gallus ) experimentally infected with HPAI H5N1 virus. The tissues were stored at +4°C or +20°C, and viral isolation was performed at different times for 360 days. The maximum periods for viral survival were observed in samples stored at +4°C in all tissue types and were 240 days in feather tissues, 160 days in muscle, and 20 days in liver. The viral infectivity at +20°C was maintained for a maximum of 30 days in the feather tissues, 20 days in muscle, and 3 days in liver. The viral inactivation rates partly overlapped in the feather and muscle tissues at the two temperatures. The virus was inactivated rapidly in the liver. Our experimental results indicate that the tissue type and temperature can greatly influence the survival of HPAI H5N1 virus in the tissues of infected chickens. IMPORTANCE Highly pathogenic avian influenza virus of the H5N1 subtype can cause massive losses of poultry, and people need to handle a large number of chicken carcasses contaminated with the virus at outbreak sites. This study evaluated how long the virus can keep its infectivity in the three types of tissues derived from chickens infected with the virus. Our experimental results indicate that the virus can survive in tissues for a specific period of time depending on the tissue type and temperature. Our results are valuable for better understanding of viral ecology in the environment and for reducing the risk of the virus spreading via bird tissues contaminated with the virus.