In the early 1980s, a large number of cases of Kaposi’s sarcoma, a previously rare skin cancer, began to appear in epidemic proportions among gay men. This was one of the early warning signs that led to identification of the AIDS epidemic and HIV. Eventually a new virus, human herpes virus 8 (HHV-8), was identified as the cause of Kaposi’s sarcoma in immunocompromised individuals. HHV-8 was first characterized in 1994 and is the latest addition to the family of human herpes viruses that includes the agents of mononucleosis, chicken pox, and genital herpes, among other diseases. The virus is thought to cause problems mainly among individuals with a compromised immune system. A group of researchers at the Fred Hutchinson Cancer Research Center has reported evidence that suggests kissing may be an important route of transmission for HHV-8.

Lead author Dr. John Pauk, who conducted the study during his fellowship in infectious diseases at the UW, said that because of an association between HHV-8 infection and sexual activity, it was initially thought that the virus was likely transmitted through genital contact. However, HHV-8 has been hard to detect in genital secretions.

“We found the virus more frequently and in higher concentrations in the oral cavity, as compared to genital tract samples,” he said. The research also presented evidence that the virus can replicate in cells that line the oral cavity, this finding supports the hypothesis that the mouth is an important source of infectious virus. In contrast to HIV, which is not transmitted by kissing, data suggest that HHV-8 may be spread through mouth-to-mouth contact between partners. While infection with HHV-8 appears to be uncommon in the general population, men who have sex with men appear to be at much higher risk.