16th International AIDS Conference Toronto, Canada - August 13 - 18, 2006

THE LINK BETWEEN MULTIPLE HIV-1 EXPOSURE AND GENETIC COMPLEXITY OF STRAINS IS REINFORCED BY IDENTIFICATION OF A SECOND CIRCULATING RECOMBINANT FORM AMONG INJECTING DRUG USERS IN NORTHERN THAILAND

Int Conf AIDS. 2006 Aug 13-18;16 Abstract No. TuAa0201

S. Tovanabutra¹, G. Kijak¹, C. Beyrer², C. Gammon-Richardson¹, S. Sakkhachornphop³, M.H. Razak², T. Vongchak³, J. Jittiwutikarn⁴, M. Robb¹, V. Suriyanon³, D. Birx⁵, D. Celentano², F. McCutchan^1
1 Henry M. Jackson Foundation, US Military HIV Research Program, Rockville, United States, ² Johns Hopkins Bloomberg School of Public Health, Baltimore, United States, ³ Research Institute for Health Sciences, Chiang Mai, Thailand, ⁴ Northern Drug Treatment Center, Chiang Mai, Thailand, ⁵ Walter Reed Army Institute of Research, US Military HIV Research Program, Rockville, United States

BACKGROUND: In Thailand, HIV-1 genetic complexity is driven by co-circulation of CRF01_AE, subtype B, and CRF01_AE/B recombinants. Injecting Drug Users (IDU) are at risk for multiple HIV-1 exposure and dual infections in this group could increase the fraction of recombinant strains. In a previous study of 347 HIV-1 infected individuals enrolled in the northern Thai drug user cohort between year 1999- 2000 using very limited genotyping assays, we selected strains for complete genome sequencing and identified a new CRF, CRF15_01B.

METHODS: Using archived serum samples from the 347 IDU and new, more powerful screening tool, the Multi-region Hybridization Assay (MHAbce v.2), we genotyped 6 – 8 regions of each strain. Five samples showed a common of shift between CRF01_AE and subtype B along the genome. Sequencing of three complete genomes, amplified from plasma by RT-PCR as overlapping halfgenomes, has been completed.

RESULTS: Recombinant strains OUR 1969P, OUR 2275P and OUR 2478P were from IDUs without a history of direct epidemiological links. They shared a common structure with five breakpoints, located in gag, pol and env. Most of the genetic material was CRF01_AE with pieces of subtype B inserted in pol and in gp 41. There was a region of frequent crossover between CRF01_AE and subtype B in pol that could not be classified. Subregion trees confirmed CRF01_AE and subtype B segments with bootstrap values of 95 – 100%. These three strains establish the presence of a second, yet unnamed CRF, CRFXX_01B, in Thailand.

CONCLUSIONS: Two new CRFs and many unique recombinant forms of HIV-1 have been identified among IDU in Thailand, confirming that IDU risks contribute to the genetic complexity of the epidemic. Comprehensive prevention services for IDU and other highly exposed risk groups could help to limit the growing complexity of HIV-1 strains in Thailand.

Download PDF of this abstract.

2006-08-13
TuAa0201

Copyright © 2006 - International AIDS Society (IAS). All information and content relating to the abstracts from the 16th International AIDS Conference, such as text, graphics, logos, button icons, images, audio clips, and software is protected by copyright. Permission is hereby granted for the non-commercial use or reproduction of the information on this web site, provided that the use of such information is accompanied by an acknowledgement that IAS is the source of the information and the name of the author of the article.

AEGiS is a 501c(3) not-for-profit organization made possible through unrestricted funding from Boehringer Ingelheim, Bridgestone/Firestone Charitable Trust, Bristol-Myers Squibb Company, Elton John AIDS Foundation, GlaxoSmithKline, the National Library of Medicine, Roche / Trimeris, and donations from users like you. Always watch for outdated information. This article first appeared in 2006. This material is designed to support, not replace, the relationship that exists between you and your doctor.

AEGiS presents published material, reprinted with permission and neither endorses nor opposes any material. All information contained on this website, including information relating to health conditions, products, and treatments, is for informational purposes only. It is often presented in summary or aggregate form. It is not meant to be a substitute for the advice provided by your own physician or other medical professionals. Always discuss treatment options with a doctor who specializes in treating HIV.

Copyright ©1980, 2006. AEGiS. All materials appearing on AEGiS are protected by copyright as a collective work or compilation under U.S. copyright and other laws and are the property of AEGiS, or the party credited as the provider of the content. Permission is hereby granted for the non-commercial use or reproduction of the information herein, provided that the use of such information is accompanied by an acknowledgement that IAS is the source of the information and the name of the author of the article.