- Oral presentation
- Open Access
O112 Trends in transmitted HIV drug resistance among non-B subtypes in the UK
© Chilton et al; licensee BioMed Central Ltd. 2008
- Published: 10 November 2008
- Drug Class
- Resistance Test
- Testing Bias
- Single Dose Nevirapine
Europe is seeing more non-B subtype HIV, reflecting patterns of migration. In France in 2003, 19% of new infections were non-B subtype  and UK data showed a rise in infection acquired heterosexually in Africa: 19% in 1992, to 33% in 2006 . With the roll-out of antiretrovirals (ART) in the developing world and use of single dose nevirapine for prevention of mother-to-child transmission, reports of emerging transmitted drug resistance (TDR) among non-B subtypes have followed.
We describe trends in resistance testing and TDR in the UK with a focus on non-B subtypes, using resistance tests reported to the UK HIV drug resistance database up to end-2006. First tests from ART-naïve individuals were included. Tests performed pre-2001 were excluded to minimise testing selection bias. TDR was defined as the presence of ≥1 mutation on Shafer's list 2007. Demographic data were acquired from UK CHIC. Logistic regression was used to examine associations between subtype, demographics and prevalence of TDR.
These data suggest that TDR is significantly lower amongst non-B subtypes, with the presence of TDR decreasing more rapidly over calendar year in this group. However, we cannot exclude testing bias, especially in earlier years. Reassuringly, TDR is mainly confined to one drug class. Despite the widespread use of NNRTI in the developing world, NNRTI resistance remains significantly lower in non-B subtypes. There is a proportional increase in the resistance tests done in naïve individuals with non-B subtypes, reflecting guidelines.