Researchers find oral transmission of HIV possible

When exposed to high levels of human immunodeficiency virus (HIV), the cells lining the mouth can develop a low-level infection, a finding that increases our understanding of the risks of oral transmission of the disease. Researchers from Charles R. Drew University and the University of California, Los Angeles, report their findings in the March 2003 issue of the Journal of Virology. "The majority of HIV type 1 infections occur via mucosal contact, and there are several reports indicating that the oral mucosa may be one route of exposure," say the researchers. "It is difficult to confirm that oral mucosa is a major transmission portal because of the correlation between oral-genital contact and other transmission risk behaviors."From the American Society for Microbiology:
ORAL TRANSMISSION OF HIV IS POSSIBLE

When exposed to high levels of human immunodeficiency virus (HIV), the cells lining the mouth can develop a low-level infection, a finding that increases our understanding of the risks of oral transmission of the disease. Researchers from Charles R. Drew University and the University of California, Los Angeles, report their findings in the March 2003 issue of the Journal of Virology.

"The majority of HIV type 1 infections occur via mucosal contact, and there are several reports indicating that the oral mucosa may be one route of exposure," say the researchers. "It is difficult to confirm that oral mucosa is a major transmission portal because of the correlation between oral-genital contact and other transmission risk behaviors."

In the study, the researchers tested the ability of HIV to infect oral mucosal cells known as normal human oral keratinocytes (NHOK). They found that when exposed to high concentrations of the virus, the cells established a low-level, productive infection that could subsequently transfer to other cells in the body.

"Human saliva contains several types of anti-HIV activity that may help protect an individual against a small virus inoculum. However, if individuals are exposed to inocula containing a heavy viral load, it is conceivable that the oral epithelium could be infected and thus serve as a beachhead for HIV-1 infection," say the researchers.

March 18, 2003