Multiple routes of hepatitis C virus transmission among injection drug users in Hai Phong, Northern Vietnam

✍ Scribed by Tomoaki Tanimoto; Nguyen Hung Cuong; Azumi Ishizaki; Phan Thi Thu Chung; Hoang Thi Thanh Huyen; Nguyen Vu Trung; Seiji Kageyama; Shinichi Oka; Pham Van Thuc; Hiroshi Ichimura

• Book ID: 102905401
• Publisher: John Wiley and Sons
• Year: 2010
• Tongue: English
• Weight: 585 KB
• Volume: 82
• Category: Article
• ISSN: 0146-6615
• DOI: 10.1002/jmv.21787

✦ Synopsis

Abstract

To identify hepatitis C virus (HCV) transmission routes among injection drug users in Northern Vietnam, plasma samples were collected from 486 drug users in Hai Phong. Plasma viral RNA was extracted from 323 (66.5%) samples that were positive for anti‐HCV antibodies. Portions of the HCV 5′‐untranslated (5′UTR)‐Core and NS5B genes were amplified by reverse‐transcriptase polymerase chain reaction, sequenced directly, and genotyped in 194 and 195 specimens, respectively. Both regions were genotyped in 137 specimens. In the 5′UTR‐Core region, genotype 6a was predominant (32.5%), followed by genotype 1a (23.7%), genotype 1b (20.6%), and genotype 6e (14.4%). In the NS5B region, genotype 1a was predominant (42.6%), followed by genotype 1b (24.1%), genotype 6a (14.4%), genotype 3b (7.2%), and genotype 6e (5.1%). Of the 137 specimens with both regions genotyped, 23 (16.8%) showed discordant genotyping results between the two regions, suggesting possible recombination and/or dual infection. Phylogenetic analysis revealed close associations between Hai Phong strains and strains from Southern China: the Yunnan province for genotype 3b; the Guangxi province for genotype 6e; the USA for genotype 1a; and Southern Vietnam for genotypes 1a and 6e. The human immunodeficiency virus (HIV) infection rate among HCV‐infected injection drug users was 52.6–55.4% and did not differ significantly by HCV genotype. Most drug users infected with HIV‐1 [98.8% (171/173)] were co‐infected with HCV. These results suggest multiple routes of HCV transmission among injection drug users in Northern Vietnam that may also be HIV transmission routes. J. Med. Virol. 82:1355–1363, 2010. © 2010 Wiley‐Liss, Inc.