GB virus type C (GBV-C) circulation among injecting drug users (IDUs) and pregnant women residing in Buenos Aires (BA) city: a dissimilar genotype distribution among HIV [+] and HIV [-] individuals born in different Latin American countries.

TRINKS J; MAESTRI M; OLIVETO F; MINASSIAN ML; ANDREETTA AM; DEL PINO N; WEISSENBACHER MC; TORRES OW; OUBIÑA JR

Buenos Aires.

Simposio; III International Clinical Virology Simposium and Advances in Vaccines.; 2010

Pan American Society of Virology.

Background and Aims: Although no association with any known disease has been demonstrated, there is a provocative evidence of some protective effect of GBV-C among HIV infected subjects. Six GBV-C genotypes are recognized. The aims of this study were to retrospectively assess the GBV-C RNA prevalence and its genotypic diversity among IDUs and pregnant women residing in BA city and its suburbs. Methods: Serum samples and epidemiological data were collected from 100 IDUs (1998-2008) and 166 pregnant women (2008-2010) selected as follows: 66 HIV[+] and 100 HIV[-]. All samples were tested for HBV, HCV and HIV infection markers. RT-nested PCR for the 5´UT region of GBV-C RNA was carried out. Genotype assignment was done by phylogenetic analysis (PHYLIP 3.5c). Epidat 3.1 software was used for statistical analysis. Results: Among the IDUs, 79 samples were serologically [+] for HIV, 100 for HBV and 83 for HCV. GBV-C RNA was detected in 16% of the IDUs, 14 samples co-infected with HIV: GBV-C genotype 2 in 11 samples and genotype 3 in the remaining ones. Among the pregnant women, 5 samples showed seropositivity for HBV and 6 for HCV. Moreover, 39% and 15% of the HIV[-] and HIV[+] women were immigrants from Latin American countries, respectively (p<0.01). GBV-C RNA was amplified in 5% and 19.7% of the HIV[-] and HIV[+] samples, respectively (p<0.01). While GBV-C genotype 2 prevailed also among the HIV[+] pregnant group (92%), 60% of the HIV[-] pregnant samples were assigned to genotype 3 (p<0.01). Interestingly, all samples ascribed to genotype 3 belonged to immigrant women who had experienced their initial sexual intercourses in their birth countries, i.e. Bolivia or Peru (p<0.01). Conclusions: a) GBV-C RNA prevalence among HIV[+] IDUs was similar to HIV[+] pregnant women (p>0.05), as was the case when comparing HIV[-] IDUs and HIV[-] pregnant women (p>0.05); and b) genotype 2 was prevalent among both IDUs from BA city and those women born in the same place, in contrast to the genotype 3 observed among mothers coming from other Latin American countries with predominant indigenous populations.