In 2004, HIV-1 infection among Taiwanese injection drug users (IDUs) started to surge. In 2007, a resurgence of HIV-1 epidemic among men having sex with men (MSM) occurred. We conducted a molecular epidemiological study of HIV-1 among different risk groups in Taiwan from 2005 to 2008.
In total 1133 HIV-1–infected adults including 576 IDUs, 464 MSM, and 93 heterosexuals were recruited. HIV-1 subtypes were determined using nested multiplex polymerase chain reaction and phylogenetic analysis. Dual infection was confirmed using cloning, sequencing, and heteroduplex mobility assay.
Among HIV-1/AIDS subjects, 96.1% MSM and 62.5% heterosexual males were infected with subtype B, whereas 66.7% female heterosexuals were infected with CRF01_AE. Most IDUs (84.5%) were infected with CRF07_BC. Four heterosexual males, 2 females and 2 MSM who were not IDUs had CRF07_BC. Forty-nine patients had CRF07_BC/subtype B dual infection and 44 (89.8%) were IDUs. Multivariate logistic regression showed that the odds ratio for dual infection among IDUs who shared syringes >5 times per month was 4.7 (95% confidence interval = 1.3 to 17.7). Phylogenetic analyses revealed that there were 2 main groups of CRF07_BC strains with sporadic transmission between different risk groups. Among 10 IDUs infected with CRF01_AE, 7 cases were clustered with an outbreak happened in 2005 and 3 cases were clustered with other strains from heterosexual population.
In Taiwan, 7.8% of HIV-1–infected IDUs had dual infection. It may have important impact to their clinical management. Although CRF07_BC was still remained in IDUs, it has spread to MSM and heterosexual populations.
*AIDS Prevention and Research Center, National Yang-Ming University, Taipei, Taiwan
†Institute of Public Health, National Yang-Ming University, Taipei, Taiwan
‡Department of Urology, Mackay Memorial Hospital, Taipei, Taiwan
§Mackay Medicine, Nursing and Management College, New Taipei City, Taiwan
‖Institute of Population Health Sciences, National Health Research Institutes, Miaoli, Taiwan
¶Department of Medical Research, Mackay Memorial Hospital, Taipei, Taiwan
#Department of Infectious Diseases, Taipei Veterans General Hospital, Taipei, Taiwan
**Department of Infectious Diseases, Taichung Veterans General Hospital, Taichung, Taiwan
††Department of Infectious Diseases, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan
‡‡Department of Infectious Diseases, China Medical University Hospital, Taichung, Taiwan
§§Department of Microbiology, School of Medicine, National Yang-Ming University, Taipei, Taiwan.
Correspondence to: Yi-Ming Arthur Chen, PhD, AIDS Prevention and Research Center, National Yang-Ming University, Li-Nong Street, Section 2, Taipei, Taiwan 112 (e-mail: email@example.com).
Supported in part by two grants from the Centers for Disease Control of the Department of Health of the Republic of China (DOH95-DC-1109 and DOH97-DC-1202) and a grant from Ministry of Education of the Republic of China (Genomic Research Center of the National Yang-Ming University, Top University and Center Grant).
Parts of this paper have been presented at the 15th International Bioinformatics Workshop on Virus Evolution and Molecular Epidemiology held in Rotterdam, the Netherlands in 2009.
The authors have no conflicts of interest to disclose.
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Received September 9, 2011
Accepted December 6, 2011