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PAPERS: UK Group on Transmitted HIV Drug Resistance Time trends in primary resistance to HIV drugs in the United Kingdom: multicentre observational study BMJ 2005; 331: 1368 [Abstract] [Full text]

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HIV-1 drug resistance in primary infections in the UK

Julie M Fox, Jonathan Weber, Sarah Fidler   (10 January 2006)

HIV-1 drug resistance in primary infections in the UK 10 January 2006
Julie M Fox, Clinical Lecturer Imperial College, Jonathan Weber, Sarah Fidler Send response to journal: Re: HIV-1 drug resistance in primary infections in the UK	EDITOR--The UK Group on Transmitted HIV Drug Resistance reports an estimated prevalence of transmitted HIV drug resistance in 14.2% between 1996 and 2003 which is increasing over time.1 Using the same definition of drug resistance (dr-HIV) as the UK Group, a study of primary HIV infection (PHI) at St Mary's Hospital, London between 2000 and 2005 showed that both the prevalence (N=9/140) and annual incidence of transmitted dr-HIV has remained low and stable at 6%. Resistance to nucleoside reverse transcriptase inhibitors was detected in 1/9, non-nucleoside reverse transcriptase inhibitors in 5/9, protease inhibitors in 1/9 and to more than one class of drug in 2/9. The disparity in estimated prevalence of transmitted dr-HIV is interesting and may reflect the differences between the two cohorts. In our cohort, all individuals acquired HIV within six months of baseline genotyping and were predominantly white with homosexually acquired B clade viruses (125/140, 89%). The UK group described a large cohort of 2357 individuals with chronic HIV infection presumed to be antiretroviral therapy (ART) naive. Of these, 172 (7%) were infected within the previous 18 months, 22% of whom had dr-HIV. The country of acquisition of HIV infection may contribute to the disparity since the use of ART globally differs considerably; as in the use of Nevirapine to prevent mother to child transmission2,3. 98% of our patients were infected in the UK. Although this was not assessed by the authors, the diversity of viral clades reported, implies greater HIV acquisition outside of the UK4. The advantage of prospectively recruiting individuals with PHI and confirmed ART naïve avoids the difficulties acknowledged by the group in relying on patient and physician reported treatment histories. It is our belief that prevalence estimates of transmitted dr-HIV in newly infected patients may not therefore be generalized to patients with established infection who are reportedly ART naive. References 1. UK Group on Transmitted HIV Drug Resistance. Time trends in primary resistance to HIV drugs in the United Kingdom: multicentre observational study. BMJ 2005;331:1368 2. McIntyre J Prevention of mother-to-child transmission of HIV: treatment options. Expert Rev Anti Infect Ther. 2005 Dec;3(6):971-80 3. Jourdain G, Ngo-Giang-Huong N, Le Coeur S, Bowonwatanuwong C, Kantipong P, Leechanachai P, Ariyadej S, Leenasirimakul P, Hammer S, Lallemant M; Perinatal HIV Prevention Trial Group. Intrapartum exposure to nevirapine and subsequent maternal responses to nevirapine-based antiretroviral therapy. N Engl J Med. 2004 Jul 15;351(3):229-40. Epub 2004 Jul 9 4. Tatt ID, Barlow KL, Clewley JP, Gill ON, Parry JV. Surveillance of HIV -1 subtypes among heterosexuals in England and Wales, 1997-2000. J Acquir Immune Defic Syndr. 2004 Aug 15;36(5):1092-9. Competing interests: None declared