Occurrence of oral shedding of retroperitoneal fibromatosis-associated herpesvirus and lymphocryptovirus in free-ranging macaques, Thailand

Oropharyngeal swabs of 262 free-ranging macaques (Macaca fasicularis and M. mulatta) were tested for Herpesviridae. The occurrence was 24.4% (64/262), and no macaques showed clinical signs of the disease. The virus was restricted to the northern and north-eastern regions of Thailand. DNA polymerase genes of the 64 positive samples were then characterized and analyzed. Eight samples (3.1%) were found to be closely related to retroperitoneal fibromatosis-associated herpesvirus (RFHV) and were classified in the genus Rhadinovirus, subfamily Gammaherpesvirinae. The phylogram of the virus revealed it to be species-specific within the macaque population. A total of 56 samples (21.4%) exhibited a nucleotide relationship with lymphocryptovirus (LCV) in the genus Lymphocryptovirus, subfamily Gammaherpesvirinae. The gender of the macaques did not significantly correlate with gammaherpesvirus infection. Our results indicate that LCV is endemic in the macaque population in Thailand, but RFHV is not endemic.