Human herpesvirus-8 infection and oral shedding in Amerindian and non-Amerindian populations in the Brazilian Amazon region.

Laboratory of Virology, São Paulo Institute of Tropical Medicine and Department of Infectious and Parasitic Diseases, School of Medicine, University of São Paulo, São Paulo, Brasil.
The Journal of Infectious Diseases (Impact Factor: 5.78). 09/2007; 196(6):844-52. DOI: 10.1086/520549
Source: PubMed

ABSTRACT Human herpesvirus type 8 (HHV-8) is hyperendemic in Amerindian populations, but its modes of transmission are unknown.
Antibodies against either HHV-8 lytic antigen or HHV-8 latency-associated nuclear antigen (LANA) were detected, by immunofluorescence assays, in 339 Amerindians and 181 non-Amerindians from the Brazilian Amazon. Serological markers of oro-fecal (hepatitis A), parenteral (hepatitis B and C), and sexual (herpes simplex virus type 2 and syphilis) transmission were measured by specific ELISAs. Salivary HHV-8 DNA was detected by use of a nested polymerase chain reaction assay and was sequenced.
Antibodies against either lytic antigen or LANA were detected in 79.1% of Amerindians and in 6.1% of non-Amerindians (adjusted seroprevalence ratio [SR], 12.63 [95% confidence interval {CI}, 7.1-22.4]; P<.0001). HHV-8 seroprevalence increased with age among Amerindians (P(Trend) < .001) and already had high prevalence in childhood but was not sex specific in either population. The 2 populations did not differ in seroprevalence of oro-fecal or parenteral markers, but seroprevalence of markers of sexual transmission was lower among Amerindians. HHV-8 DNA in saliva was detected in 47 (23.7%) of 198 HHV-8 seropositive Amerindians. Detection of HHV-8 DNA decreased with age (P(Trend) < .04) and was more common in men (SR, 2.14 [95% CI, 1.3-3.5]; P=.003). A total of 36 (76.6%) of the 47 saliva HHV-8 DNA samples were sequenced, and all clustered as subtype E.
The data support the hypothesis of early acquisition and horizontal transmission, via saliva, of HHV-8 subtype E in Amerindian populations.