Da-Young Kim, Yong-Myung Kang, Yeon-Hee Kim, Hae-Eun Kang, Dae-Sung Yoo, Ki-Hyun Cho
ASFV shows strong temperature-dependent environmental resistance, with increased risk of indirect transmission under cold conditions, which supports the establishment of effective quarantine strategies for ASF control.
BACKGROUND: African swine fever (ASF) is a highly fatal swine disease caused by the ASF virus (ASFV), resulting in substantial socio-economic impacts in affected regions worldwide. The remarkable environmental stability and tenacity of ASFV play a critical role in indirect transmission through contaminated carcasses and fomites. Thus, this study aimed to investigate the survival of ASFV in multiple sample types relevant to potential indirect transmission routes.
MATERIALS AND METHODS: The stability and tenacity of ASFV in whole blood, oral and rectal swabs, and tissues, including the spleen, liver, kidney, and muscle, were evaluated under four temperature conditions (-20°C, 4°C, 21°C, and 37°C) over defined storage periods using quantitative real-time polymerase chain reaction and virus titration with statistical analysis.
RESULTS: ASFV stability and tenacity were significantly influenced by sample type, storage temperature, and incubation time, exhibiting a clear inverse relationship with temperature. Whole blood showed the highest tenacity, maintained for up to 168 days at -20°C and 4°C. Viral genomes and infectivity in tissue and swab samples were better preserved at lower temperatures, whereas infectivity rapidly declined at higher temperatures.
CONCLUSIONS: ASFV shows strong temperature-dependent environmental resistance, with increased risk of indirect transmission under cold conditions, which supports the establishment of effective quarantine strategies for ASF control.