Evidence for a "Founder Effect" among HIV-infected injection drug users (IDUs) in Pakistan

BMC Infect Dis. 2010 Jan 12:10:7. doi: 10.1186/1471-2334-10-7.


Background: We have previously reported a HIV-1 subtype A infection in a community of injection drug users (IDUs) in Karachi, Pakistan. We now show that this infection among the IDUs may have originated from a single source.

Methods: Phylogenetic analysis was performed of partial gag sequences, generated using PCR, from 26 HIV-positive IDU samples.

Results: Our results showed formation of a tight monophyletic group with an intra-sequence identity of < 98% indicating a "founder effect". Our data indicate that the HIV-1 epidemic in this community of IDUs may have been transmitted by an HIV positive overseas contract worker who admitted to having contact with commercial sex workers during stay abroad.

Conclusion: Specific measures need to implemented to control transmission of HIV infection in Pakistan through infected migrant workers.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Drug Users*
  • Founder Effect*
  • HIV Infections / epidemiology*
  • HIV-1 / classification
  • HIV-1 / genetics*
  • Humans
  • Male
  • Pakistan / epidemiology
  • Phylogeny
  • Population Surveillance
  • RNA, Viral / genetics
  • Sequence Alignment
  • Sequence Analysis, RNA
  • Sex Work
  • Transients and Migrants
  • Young Adult


  • RNA, Viral