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. doi: 10.1097/00126334-200408150-00013.


The molecular diversity and demographic characteristics among 976 anti-HIV-1-positive heterosexuals attending 15 sexually transmitted infection (STI) clinics participating in an unlinked anonymous HIV prevalence serosurvey in England and Wales during 1997-2000 were investigated. Subtypes were assigned by heteroduplex mobility assay or sequencing of the p17/p24 region of gag and the V3/V4 region of env and by sequencing of the protease gene. Overall, there was no significant change in the subtype distribution, with subtype C accounting for the majority (32%) of subtyped infections. Subtypes B (29%), A (12%), circulating recombinant forms (CRFs, 9%), unique recombinant forms (URFs, 8%), and subtypes D-H (8%) were also detected. Thirty-nine percent of infections in men were with subtype B, whereas subtype C was most common (38%) in women. Logistic regression analyses showed the relative risk (RR) of infection with a non-B subtype, compared with subtype B, to be greater in African-born individuals (RR = 28.9, P < 0.01), among newly diagnosed infections (RR = 3.4, P < 0.01), and in women (RR = 2.4, P < 0.01). These findings indicate a high level of genetic diversity among HIV-infected heterosexual STI clinic attendees in England and Wales. Recently, subtype C has become most prevalent, particularly in younger age groups, suggesting recent acquisition of this viral strain. The high proportion of non-B, CRF, and URF infections among UK-born individuals is consistent with mixing between migrants and UK-born individuals in England and Wales. As migration patterns change, continued monitoring of HIV genetic diversity will aid understanding of transmission patterns.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Africa / ethnology
  • Algorithms
  • Asia / ethnology
  • England / epidemiology
  • Europe / ethnology
  • Female
  • Genes, env
  • Genes, gag
  • Genes, pol
  • Genetic Variation
  • HIV Infections / classification*
  • HIV Infections / epidemiology
  • HIV Infections / virology*
  • HIV-1 / classification*
  • HIV-1 / genetics
  • HIV-1 / isolation & purification
  • Heterosexuality
  • Humans
  • Male
  • Population Surveillance
  • Recombination, Genetic
  • Risk Factors
  • Wales / epidemiology