The effect of temperature and UV light on infectivity of avian influenza virus (H<inf>5</inf>N<inf>1</inf>, Thai field strain) in chicken fecal manure

Abstract

Normal chicken fecal manure (pH 8.23 and 13.7% moisture) was investigated for infectivity of the avian influenza virus (AIV; H5N1). The manure was divided into three groups; each group was inoculated with AIV at 2.38 × 105.25ELD50. After viral inoculation, the first group was incubated at 25°C. The second group was kept at 40°C, and the last group was exposed to ultraviolet light at 4-5 μw/cm2at room temperature. After incubation, a 20% suspension of manure was filtered and the filtrates were inoculated into 9-11 day-old embryonated chicken eggs per WHO protocol (2002). The results showed that at 25°C the virus lost its infectivity within 24 hours, and at 40°C within 15 minutes. UV light, however, could not destroy the infectivity of the virus even after exposure for 4 hours.