Investigating African swine fever virus susceptibility across seven genera of pigs and peccaries using peripheral blood mononuclear cells

Abstract

African swine fever (ASF), a viral haemorrhagic fever of suids, has recently transformed from an exotic disease to a panzootic threat to domestic and wild suids worldwide. By 2023, ASF had reached large parts of Europe and Asia, parts of the Americas, and with the Democratic Republic of Timor-Leste the doorstep of Australia. The disease is caused by a large and very complex DNA virus of the genus Asfivirus in the family Asfarviridae that replicates primarily in monocytes and macrophages. So far, susceptibility to ASF virus (ASFV) has only been shown for members of the Suidae family. With regard to members of the Tayassuidae family, only collared peccaries Dicotyles tajacu have been investigated and showed no obvious susceptibility. In the present study, the susceptibility of peccaries was further investigated using blood-derived monocytic cells from a collared peccary, a Chacoan peccary Catagonus wagneri and a white-lipped peccary Tayassu pecari from European zoos. Viral replication was monitored using indirect immunofluorescence staining and hemadsorption tests. Unlike cells from Suidae including domestic pigs Sus scrofa domesticus, wild boar S. scrofa, bearded pig S. barbatus, Visayan warty pig S. cebifrons, Sulawesi babirusa Babyrousa celebensis, red river hog Potamochoerus porcus and warthog Phacochoerus africanus, Tayassuidae macrophages did not support ASFV replication and thus susceptibility is highly unlikely. There is no evidence that peccaries could play any role in ASF epidemiology.