Khan Anis, Al Balwi Mohammed, AlAyyar Latifah, AlAbdulkareem Ibrahim, Albekairy Abdulkareem, Aljumah Abdulrahman
Department of Medical Genomics Research, King Abdullah International Medical Research Center, Ministry of National Guard Health Affairs, Riyadh 11426, Saudi Arabia.
Department of Medical Genomics Research, King Abdullah International Medical Research Center, Ministry of National Guard Health Affairs, Riyadh 11426, Saudi Arabia; Department of Pathology and Laboratory Medicine, King Abdulaziz Medical City, Ministry of National Guard Health Affairs, Riyadh 11426, Saudi Arabia; College of Medicine, King Saud bin Abdulaziz University for Health Sciences, Ministry of National Guard Health Affairs, Riyadh 11426, Saudi Arabia.
Infect Genet Evol. 2017 Aug;52:82-88. doi: 10.1016/j.meegid.2017.04.024. Epub 2017 Apr 27.
HCV genotype 4 is highly prevalent in many Middle Eastern countries, yet little is known about the genotype's epidemic history at the subtype-level in this region. To address the dearth of data from Saudi Arabia (SA) we genotyped 230 HCV isolates in the core/E- and NS5B-region and analyzed using Bayesian phylogenetic approaches. HCV genotype 4 (HCV/4) was positive in 61.7% (142/230) of isolates belonging to 7 different subtypes with the predominance of 4d (73/142; 51.4%) followed by 4a (51/142; 35.9%). Phylogenetic analysis also revealed a distinct epidemiological cluster of HCV/4d for Saudi Arabia. HCV/1 appeared as the second most prevalent genotype positive in 31.3% (72/230) of isolates with the predominance of 1b (53/72; 73.6%) followed by 1a (16/72; 22.2%), and 1g (3/72; 4.1%). A small proportion of isolates belonged to HCV/3a (12/230; 5.2%), and HCV/2a (4/230; 1.7%). We estimate that the genotype 4 common ancestor existed around 1935 (1850-1985). Genotype 4 originated plausibly in Central Africa and multiple subtypes disseminated across African borders since ~1970, including subtype 4d which dominates current HCV infections in Saudi Arabia. The Bayesian skyline plot (BSP) analysis showed that genotype 4d entered the Saudi population in 1900. The effective number of HCV infections grew gradually until the second half of the 1950s and more rapidly until the early-80s through the use of imported blood units and blood products. Subsequently, the rate of HCV infection in the Saudi Arabian population was stabilized through effective screening of blood and infection control measures.
丙型肝炎病毒（HCV）4型在许多中东国家高度流行，但该地区该基因型在亚型水平的流行病史却鲜为人知。为了填补沙特阿拉伯（SA）的数据空白，我们对230株HCV分离株的核心/E区和NS5B区进行了基因分型，并采用贝叶斯系统发育方法进行分析。在属于7种不同亚型的分离株中，61.7%（142/230）的HCV 4型（HCV/4）呈阳性，其中4d亚型占主导（73/142；51.4%），其次是4a亚型（51/142；35.9%）。系统发育分析还揭示了沙特阿拉伯HCV/4d的一个独特的流行病学集群。HCV/1型是第二常见的基因型，在31.3%（72/230）的分离株中呈阳性，其中1b亚型占主导（53/72；73.6%），其次是1a亚型（16/72；22.2%）和1g亚型（3/72；4.1%）。一小部分分离株属于HCV/3a（12/230；5.2%）和HCV/2a（4/230；1.7%）。我们估计4型基因型的共同祖先大约存在于1935年（1850 - 1985年）。4型基因型可能起源于中非，自1970年左右以来，多种亚型跨越非洲边界传播，包括在沙特阿拉伯目前HCV感染中占主导的4d亚型。贝叶斯天际线图（BSP）分析表明，4d基因型于1900年进入沙特人群。通过使用进口血液单位和血液制品，HCV感染的有效数量逐渐增加，直到20世纪50年代后半期，在80年代初之前增长更快。随后，通过有效的血液筛查和感染控制措施，沙特阿拉伯人群中的HCV感染率趋于稳定。
