Pending problem of "silent" human immunodeficiency virus infection.

The problem of "silent" HIV infection is reviewed. Overall, the number of proven "silent" infection in several at-risk populations, including HIV exposed health-care workers, homosexuals, IV drug addicts and children born to HIV-infected mothers, has been very low. Contrary to these observations, we describe a very high prevalence of HIV specific immunity and positive HIV specific PCR signals in an Ethiopian immigrant population recently arrived in Israel. The interpretation of these findings is not entirely clear but we suggest that host immunity and probably different handling of the infection may account for the longer persistence of viral components in the body. Further studies are required to determine the amount and nature of these viral elements and, most importantly, whether they are still infectious.