Searching for antibodies to HHV-8 in children born to HIV-1 infected mothers from São Paulo, Brazil: relationship to maternal infection.

With the spread of AIDS, many HIV-1 infected women and children have been diagnosed with Kaposi's sarcoma (KS), mostly in Africa. Since the discovery of the causative agent of KS (human herpesvirus 8, HHV-8) several seroepidemiological studies have been conducted to identify groups at risk of KS. The present study was conducted in order to add some information from São Paulo, Brazil. We searched for HHV-8 antibodies in plasma samples obtained from a cohort of 108 children born to HIV-1 infected mothers, and from 15 mother-child pairs enrolled in a longitudinal study of HIV-1 vertical transmission. An in house immunofluorescence assay was used to detect anti-latent and anti-lytic HHV-8 antibodies based on the BCBL-1 cell line. No case of anti-latent antibodies and a 7.4 per cent frequency of anti-lytic antibodies were detected among children. Interestingly, the detection of HHV-8 antibodies varied according to the children's HIV-1 status; no antibodies were detected in HIV-1 non-infected children and 10.9 per cent and 8.3 per cent frequencies of antilytic antibodies in truly HIV-1 infected children and in children in whom the HIV-1 status could not be defined. Since concordant results were obtained by the analysis of plasma samples obtained from mother-child pairs and considering the children's age, the antibodies detected in the present study probably reflect maternal antibodies. Unfortunately, we were not able to determine if any case of KS occurred among mothers, but because of the risk of HHV-8 horizontal transmission, the results obtained prompt us to continue investigating groups at risk to acquire HHV-8 and to search for preventive measures to avoid virus transmission.