Molecular epidemiology of dual HIV-1/HIV-2 seropositive adults from Senegal, West Africa

AIDS Res Hum Retroviruses. 2003 Jul;19(7):575-84. doi: 10.1089/088922203322230941.


Dual infection with HIV-1 and HIV-2 can occur in locales where these viruses co-circulate, most commonly in West Africa. Although dual seropositivity is common in this region, the true rate of dual infection remains unclear. In addition, whether unique HIV-1 subtypes are circulating in dually infected individuals is unknown. A cohort of 47 HIV-1 and HIV-2 dually seropositive individuals from Senegal, West Africa was screened for the presence of HIV-1 and HIV-2 gag and env PBMC viral DNA sequences using PCR. Of the 47 dual HIV-1/HIV-2 seropositive individuals tested, 19 (40.4%) had infection with both HIV-1 and HIV-2 confirmed by genetic sequence analysis, whereas only HIV-1 or HIV-2 was confirmed in 17 (36.2%) or 9 (19.1%), respectively. The majority of HIV-1 subtypes found were CRF-02 and A, although subtypes D, C, G, J and B were also found, reflecting the subtypes known to be circulating in Senegal. There was no significant difference in HIV-1 subtype distribution between individuals with confirmed dual infection and patients in this study with dual seropositivity but lacking HIV-2, or with HIV-1 infected patients within the general population in Senegal, although the study was underpowered to detect anything but large differences. The prevalence of HIV-1/HIV-2 dual infection appears to be significantly less than that of dually seropositive individuals and this likely reflects cross-reactive serology. The common HIV-1 subtypes prevalent in West Africa (CRF-02 and subtype A) have a similar distribution to those found in our cohort of dually infected and dually seropositive subjects.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adolescent
  • Adult
  • Cohort Studies
  • DNA, Viral / genetics
  • DNA, Viral / isolation & purification
  • Female
  • Genes, env
  • Genes, gag
  • HIV Seropositivity / epidemiology*
  • HIV Seropositivity / virology
  • HIV-1 / isolation & purification*
  • HIV-2 / isolation & purification*
  • Humans
  • Male
  • Middle Aged
  • Molecular Sequence Data
  • Phylogeny
  • Polymerase Chain Reaction
  • Senegal / epidemiology
  • Sequence Homology, Nucleic Acid
  • Seroepidemiologic Studies


  • DNA, Viral

Associated data

  • GENBANK/AY249755
  • GENBANK/AY249756
  • GENBANK/AY249757