The human herpesvirus 8 (HHV-8) is the etiologic agent of Kaposi's sarcoma, cancer that often affects HIV-positive and some specific populations. The routes of transmission of HHV-8 are still poorly understood, and sexual is considered the main route in men who have sex with men. Epidemiological studies indicate that saliva can play an important role in HHV-8 transmission. In addition, studies showed that the virus is found more frequently in saliva than in blood or genital and anal secretions. Saliva presents low detection percentages of HHV-8 when studied in isolated samples, but have a significant increase in successive samples obtained over time, thus showing a potential intermittent pattern in excretion. The lack of a standard technique for saliva collection difficult studies comparison. The correlation between oral excretion, viremia, and serological profile of HHV-8 is still poorly understood, with conflicting reports in the literature. The aim of this study is to analyze the dynamics of HHV-8 oral excretion in subjects in which the virus seroprevalence is known to be higher: men who have sex with HIV negative men and HIV positive men and women. At first, an anti-HHV-8 serologic profile will be drawn using ELISA and indirect immunofluorescence techniques. In HHV-8 seropositive patients, an oral excretion profile will be defined over 3 months, with daily collections of saliva and every other week peripheral blood for quantitative PCR HHV-8 detection. Detection will be held simultaneously in whole blood, plasma, leukocyte cream and induced peripheral B lymphocytes aiming to define the best way to detect HHV-8 in peripheral blood. Six months after the first stage, the study will be repeated in the same groups. The virus oral excretion pattern will be analyzed taking into account viremia, antibody vs. lytic antigens profile, HHV-8 latency profile, patient behavior and sexual habits and also some clinical parameters (levels of CD4, CD8, HIV viral load). Preceding the study, a comparative analysis will be performed using different methods of saliva collection to obtain viral DNA, aiming to establish which method is ideal for use in prospective studies with saliva samples. The results obtained will allow an advance in HHV-8 saliva excretion characterization in immunocompetent individuals, which in turn may help to elucidate HHV-8 transmission routes in this population. Additionally, we will set a saliva sample biorepository that will allow, in the future, the oral excretion dynamics study of other viruses of interest in human pathology.
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