Evaluation of transmitted HIV drug resistance among recently-infected antenatal clinic attendees in four Central African countries.

Virology Laboratory CRESAR/IMPM/Institut de Recherche pour le Développement, Yaoundé, Cameroon.
Antiviral therapy (Impact Factor: 3.14). 01/2009; 14(3):401-11.
Source: PubMed

ABSTRACT The rapid expansion of antiretroviral treatment in resource-limited settings is raising concerns regarding the emergence and transmission of HIV drug resistance (HIVDR). We evaluated the extent of transmission of drug-resistant HIV strains in four Central African countries: the Republic of Congo, Central African Republic, Chad and Cameroon.
The World Health Organization (WHO) HIVDR threshold survey was implemented in major treatment areas in each country. Pregnant women who were aged <25 years, who were at first pregnancy and who were HIV type-1-positive were enrolled at each site in 2006-2007 for genotyping. HIVDR prevalence was categorized using the WHO threshold survey binomial sequential sampling method.
The prevalence of HIVDR in Brazzaville and Bangui sites could not be classified because the eligible sample number was not reached. HIVDR prevalence was low (<5%) in N'Djamena for all drug classes. In Yaoundé, we found one individual with the D67D/N mutation and two with K103N. HIVDR prevalence was categorized as low (<5%) for protease inhibitors (PIs) and nucleoside reverse transcriptase inhibitors (NRTIs), and moderate (> or =5-< or =15%) for non-NRTIs (NNRTIs). HIVDR prevalence in Douala was low for PIs and NNRTIs, and moderate for NRTIs as we identified one individual with M184V plus K101E plus G190A mutations and a second with D67D/N.
The moderate HIVDR prevalence found in Yaoundé and Douala indicate that efforts should be made in Cameroon to prevent HIVDR; however, additional surveys are needed to confirm this trend. This study highlighted challenges presented by the WHO methodology, such as additional costs, workload, difficulties in acquiring even small sample numbers and the necessity for better quality assurance of HIV testing and record keeping at antenatal clinics.

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