LONG-TERM PERSISTENT INFECTION OF SWINE MONOCYTES MACROPHAGES WITH AFRICAN SWINE FEVER VIRUS/

Long-term persistent infection was established in 100% of pigs (n = 19 ) experimentally infected with African swine fever virus (ASFV). Viral DNA was detected in peripheral blood mononuclear leukocytes (PBML) at greater than 500 days postinfection by a PCR assay. Infectious virus was not, however, isolated from the same PBML samples. In cell fractio nation studies of PBML, monocytes/macrophages were found to harbor vir al DNA during the persistent phase of infection. This result indicates that monocytes/macrophages are persistently infected with ASFV and th at ASFV-swine monocyte/macrophage interactions can result in either ly tic or persistent infection.