Researchers have known for some time that people may harbor the AIDS virus without showing symptoms or even producing telltale antibodies. But the duration of such latent infections has been uncertain. Now a study has shown that some people may carry the AIDS virus for three years or longer without its being detected by widely used antibody screening tests. If the results are confirmed, they could mean that latent AIDS infection is more common than was once believed.
The study, reported last week in the New England Journal of Medicine, followed 133 men without AIDS antibodies who continued to engage in...