Developments in Brief : Unrelated Virus May Activate AIDS Illness

New studies suggest that a dormant AIDS virus can be activated by unrelated viruses, and this may explain why some people infected with the AIDS virus do not develop any symptoms until years later, a scientist says.

The test-tube research also suggests that diet, drugs or other environmental factors may be able to activate a dormant virus of the acquired immune deficiency syndrome, said researcher Dr. Malcolm Martin of the National Institute of Allergy and Infectious Diseases.

In a report in the Proceedings of the National Academy of Sciences, he said he and colleagues studied how various viruses affected the genetic “on-off” switches that control activities of the AIDS virus.

In test tubes, they planted those switches in various kinds of human cells, and then exposed the cells to different kinds of viruses unrelated to AIDS. The other viruses included those that cause herpes, chicken pox and respiratory infections.

The results suggest that infection with those other viruses could activate a dormant AIDS virus, Martin said. And because those other viruses are so diverse, he added, it is likely that they don’t act directly on the AIDS virus, but rather achieve their effect indirectly, perhaps by affecting normal cellular proteins.