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Amplifying and Quantifying HIV-1 RNA in HIV Infected Individuals with Viral Loads Below the Limit of Detection by Standard Clinical Assays
Published on: September 26, 2011
Evidence for a "Founder Effect" among HIV-infected injection drug users (IDUs) in Pakistan
Mohammad A Rai1, Vivek R Nerurkar, Suhail Khoja
1Department of Biological and Biomedical Sciences, Aga Khan University, Karachi, Pakistan.
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.
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