Department of Microbiology and Infectious Diseases and Centre for International Health, University of Sherbrooke, Sherbrooke, Québec, Canada.
PLoS One. 2007 Apr 18;2(4):e372. doi: 10.1371/journal.pone.0000372.
Sub-Saharan Africa is the continent with the highest prevalence of Hepatitis C virus (HCV) infection. Genotype 2 HCV is thought to have originated from West Africa several hundred years ago. Mechanisms of transmission remain poorly understood.
METHODOLOGY/PRINCIPAL FINDINGS: To delineate mechanisms for HCV transmission in West Africa, we conducted a cross-sectional survey of individuals aged >or=50 years in Bissau, Guinea-Bissau. Dried blood spots were obtained for HCV serology and PCR amplification. Prevalence of HCV was 4.4% (47/1066) among women and 5.0% (27/544) among men. In multivariate analysis, the independent risk factors for HCV infection were age (baseline: 50-59 y; 60-69 y, adjusted odds ratio [AOR]: 1.67, 95% CI: 0.91-3.06; >or=70 y, AOR: 3.47, 95% CI: 1.89-6.39), belonging to the Papel, Mancanha, Balanta or Mandjako ethnic groups (AOR: 2.45, 95% CI:1.32-4.53), originating from the Biombo, Cacheu or Oio regions north of Bissau (AOR: 4.16, 95% CI: 1.18-14.73) and having bought or sold sexual services (AOR: 3.60, 95% CI: 1.88-6.89). Of 57 isolates that could be genotyped, 56 were genotype 2.
Our results suggest that transmission of HCV genotype 2 in West Africa occurs through sexual intercourse. In specific locations and subpopulations, medical interventions may have amplified transmission parenterally.
撒哈拉以南非洲是丙型肝炎病毒（HCV）感染率最高的大陆。据认为，HCV 基因型 2 起源于几百年前的西非。传播机制仍知之甚少。
方法/主要发现：为了阐明西非 HCV 传播的机制，我们对几内亚比绍比绍市年龄> = 50 岁的个体进行了横断面调查。采集了干燥血斑进行 HCV 血清学和 PCR 扩增。女性 HCV 患病率为 4.4%（47/1066），男性为 5.0%（27/544）。多变量分析表明，HCV 感染的独立危险因素包括年龄（基线：50-59 岁；60-69 岁，调整后的优势比[OR]：1.67，95%CI：0.91-3.06；> = 70 岁，OR：3.47，95%CI：1.89-6.39），属于 Papel、Mancanha、Balanta 或 Mandjako 族裔群体（OR：2.45，95%CI：1.32-4.53），来自比绍以北的 Biombo、Cacheu 或 Oio 地区（OR：4.16，95%CI：1.18-14.73），以及购买或出售性服务（OR：3.60，95%CI：1.88-6.89）。可进行基因分型的 57 个分离株中，56 个为基因型 2。
我们的研究结果表明，HCV 基因型 2 在西非的传播是通过性传播发生的。在特定地点和亚人群中，医疗干预可能会加剧经皮传播。
