An increased diversity of HCV isolates were characterized among 393 patients with liver disease in China representing six genotypes, 12 subtypes, and two novel genotype 6 variants.
ABSTRACT: We have recently determined HCV isolates among volunteer blood donors and IDUs in southern China and revealed the genotype distribution patterns not only different between the two studied cohorts but also from what we have sampled in 2002. A changed pattern could have also occurred among patients with liver disease.Both E1 and NS5B sequences of HCV were characterized among 393 patients with liver disease followed by phylogenetic analysis.Six HCV genotypes, 12 subtypes (1b: 65.9%, 6a: 17.1%, 2a: 7.4%, 3a: 3.6%, 3b: in 3.3%, 6e: 0.76%, and 1a, 1c, 2b, 2f, 4d, and 5a each 0.25%), and two novel genotype 6 variants were classified, showing the greatest complexity of HCV hitherto found in China. Although the predominance of 1b followed by 6a is largely consistent with what we have sampled in 2002, the identification of single isolates of 1c, 2f, 4d, 5a, and two novel HCV-6 variants were first reported. Excluding 4d from a European visitor, all the others were from Chinese patients. Since the 6a proportion (17.1%, 67/393) was unexpectedly lower than what we have recently detected among blood donors (34.8%, 82/236) and IDUs (51.5%, 70/136), further statistical analyses were conducted. Comparison of the mean ages showed that among the 393 patients, those infected with 1b were significantly (6.7 years) older than those with 6a, while the 393 patients as a whole were significantly older than the 236 blood donors (8.4 years) and 136 IDUs (12.6 years) we have recently reported. Explanations are that younger individuals had higher proportions of 6a infections while patients with liver disease could have acquired their infections earlier than volunteer blood donors and IDUs.Among 393 patients with liver disease, a great diversity in HCV was detected, which reflects a constantly changing pattern of HCV genotypes in China over time.
Project description:In this study, we characterized the full-length genomes of 16 HCV isolates obtained from patients in a single hospital in China using overlapping PCR followed by DNA sequencing. The obtained genomes are 9414-9628 nucleotides in length, and each genome contains a single ORF of 9021-9102 nucleotides. Nine genomes represent the common subtypes 1a, 1b, 2a, 2b, 3a, 3b, and 6a, while seven represent the infrequent lineages 1c, 2f, 4d, and 5a, and two novel genotype 6 variants. GZ51969 and GZ52540 are subtype 1b isolates belonging to two unique clusters designated A and B, which account for 29.5% and 59.5% of the 1b infections in China, respectively. ZS542 and GZ98799 represent the first two complete genomes of the provisionally assigned subtype 2f. ZS96 and ZS202 are novel genotype 6 variants that may qualify for two new subtypes. ZS17, ZS537, and ZS631 represent three alien subtypes, namely, 1c, 4d, and 5a, which were detected in China for the first time in this study and may have been recently introduced as a result of globalization. Taken together, these results confirmed a large variety of HCV taxonomic lineages in China through the sequencing of their full-length genomes. These lineages represent six genotypes, 11 subtypes, and two novel variants. They were characterized for achieving a better understanding of the HCV genetic variation patterns and for possible future research applications.
Project description:BACKGROUND: Recently, high proportions (15.6%-98.7%) of intravenous drug users (IDUs) in China were found to be positive for hepatitis C virus (HCV). Yunnan Province is located in southwestern China and borders one of the world's most important opium-producing regions, thus it is an important drug trafficking route to other regions of China. METHODOLOGY/PRINCIPAL FINDINGS: Here, we assessed 100 HCV-positive plasma samples from IDUs who were enrolled through the Kunming Center for Disease Control and Prevention in 2012. HCV C/E1 fragments were PCR-amplified and sequenced. We identified eight HCV subtypes (1a, 1b, 3a, 3b, 6a, 6n, 6u and 6v), of which genotype 6 was most predominant (frequency, 47%) followed by genotypes 3 (41%) and 1 (12%). HCV subtypes 6n (30%) and 3b (29%) were most common and were identified in 59% of the IDUs. We compared HCV genotypes among IDUs in Yunnan Province with those from other regions and found that the distribution patterns of HCV genotypes in Yunnan Province were similar to those in southern China, but different from those in eastern China. However, the distribution patterns of HCV subtypes varied among Yunnan Province and southern China, despite the shared similar genotypes. A comparison of the current data with those previously reported showed that the frequency of HCV genotype 6 increased from 25% to 47% within 5 years, especially subtypes 6a (5% to 15%) and 6n (11.2% to 30%). In contrast, the frequencies of subtypes 3b and 1b decreased by almost 50% within 5 years. CONCLUSION/SIGNIFICANCE: Our results provided further information to support the assertion that drug trafficking routes influence HCV transmission patterns among IDUs in Yunnan Province. The frequency of HCV genotypes and subtypes changed rapidly among IDUs in Yunnan Province and subtypes 6a and 6n may have originated in Vietnam and Myanmar, respectively.
Project description:More than half of intravenous drug users (IDUs) in China suffer from the Hepatitis C virus (HCV). The virus is also more prevalent in non-injection drug users (NIDUs) than in the general population. However, not much is known about HCV subtype distribution in these populations.Our research team conducted a cross-sectional study in four provinces in China. We sampled 825 IDUs and 244 NIDUs (1162 total), genotyped each DU's virus, and performed a phylogenetic analysis to differentiate HCV subtypes.Nucleic acid testing (NAT) determined that 82% percent (952/1162) of samples were HCV positive; we subtyped 90% (859/952) of these. We found multiple HCV subtypes: 3b (249, 29.0%), 3a (225, 26.2%), 6a (156, 18.2%), 1b (137, 15.9%), 6n (50, 5.9%), 1a (27, 3.1%), and 2a (15, 1.7%). An analysis of subtype distributions adjusted for province found statistically significant differences between HCV subtypes in IDUs and NIDUs.HCV subtypes 3b, 3a, 6a, and 1b were the most common in our study, together accounting for 89% of infections. The subtype distribution differences we found between IDUs and NIDUs suggested that sharing syringes was not the most likely pathway for HCV transmission in NIDUs. However, further studies are needed to elucidate how NIDUs were infected.
Project description:Recently in China, HCV 6a infection has shown a fast increase among patients and blood donors, possibly due to IDU linked transmission.We recruited 210 drug users in Shanwei city, Guangdong province. Among them, HCV RNA was detected in 150 (71.4%), both E1 and NS5B genes were sequenced in 136, and 6a genotyped in 70. Of the 6a sequences, most were grouped into three clusters while 23% represent emerging strains. For coalescent analysis, additional 6a sequences were determined among 21 blood donors from Vietnam, 22 donors from 12 provinces of China, and 36 IDUs from Liuzhou City in Guangxi Province. Phylogeographic analyses indicated that Vietnam could be the origin of 6a in China. The Guangxi Province, which borders Vietnam, could be the first region to accept 6a for circulation. Migration from Yunnan, which also borders Vietnam, might be equally important, but it was only detected among IDUs in limited regions. From Guangxi, 6a could have further spread to Guangdong, Yunnan, Hainan, and Hubei provinces. However, evidence showed that only in Guangdong has 6a become a local epidemic, making Guangdong the second source region to disseminate 6a to the other 12 provinces. With a rate of 2.737×10?³ (95% CI: 1.792×10?³ to 3.745×10?³), a Bayesian Skyline Plot was portrayed. It revealed an exponential 6a growth during 1994-1998, while before and after 1994-1998 slow 6a growths were maintained. Concurrently, 1994-1998 corresponded to a period when contaminated blood transfusion was common, which caused many people being infected with HIV and HCV, until the Chinese government outlawed the use of paid blood donations in 1998.With an origin from Vietnam, 6a has become a local epidemic in Guangdong Province, where an increasing prevalence has subsequently led to 6a spread to many other regions of China.
Project description:Recently, we studied hepatitis C virus (HCV) sera-prevalence among 559 890 first-time volunteer blood donors in China. From randomly selected 450 anti-HCV positive donors, we detected HCV RNA in 270 donors. In this study, we amplified HCV E1 and/or NS5B sequences from 236 of these donors followed by DNA sequencing and phylogenetic analysis. The results indicate new trends of HCV infection in China. The HCV genotype distribution differed according to the donors' region of origin. Among donors from Guangdong province, we detected subtypes 6a, 1b, 3a, 3b, 2a, and 1a at frequencies of 49.7%, 31.0%, 7.6%, 5.5%, 4.1%, and 2.1%, respectively. Among donors from outside Guangdong, we detected 1b, 2a, 6a, 3b, 3a, 6e, and 6n at frequencies 57.1%, 13.2%, 11.0%, 9.9%, 4.4%, 2.2%, and 2.2%, respectively. Although we found no significant differences among regions in age or gender, subtype 6a was more common (P < 0.001) in donors from Guangdong than those from elsewhere, whilst subtypes 1b (P < 0.02) and 2a (P < 0.001) were more frequent outside Guangdong. Disregarding origins, the male/female ratio was higher for subtype 6a-infected donors (P < 0.05) than for subtype 1b donors, whilst the mean age of subtype 2a donors was 8-10 years older (P < 0.05) than that for all other subtypes. Detailed phylogenetic analysis of our sequence data provides further insight into the transmission of HCV within China, and between China and other countries. The predominance of HCV 6a among blood donors in Guangdong is striking and mandates studies into risk factors for its acquisition.
Project description:The Yunnan province is the epicenter of HIV-1 epidemics in China and a center for drug trafficking to the other parts of the world. In six prefectures of this province, a total of 132 IDUs were recruited to determine the sero-prevalence of HCV and HIV-1 and the positive rates were 93.94% and 68.18%, respectively (P<0.001). Co-infection with HCV and HIV-1 was found among 89 IDUs, of whom several HCV fragments were amplified and sequenced. Sequences of the HCV 5'NCR-C and NS5B region were determined from 82 IDUs. Phylogenetic analyses showed consistent genotyping among 80 IDUs. Among them HCV genotypes 1a, 1b, 3a, 3b, 6a, 6n, and a tentatively assigned novel 6u subtype were found in 1 (1.25%), 16 (20%), 19 (23.75%), 24 (30%), 4 (5%), 9 (11.25%) and 7 (8.75%) individuals, respectively. In two IDUs, genotyping results were discordant, suggesting mixed HCV infections or recombination. The proportion of patients with HCV 1b tended to decrease from the north to south and from the east to west in this province. Genotype 3 and 6 strains were more frequent in the southern prefectures. The novel subtype 6u strains were only detected in Dehong which borders Myanmar. Our findings showed a unique pattern of HCV genotype distribution, which is similar to that in the southeastern Asian countries but distinct from that among the general population in China. Routes of drug trafficking and the resulting high prevalence of HIV-1 infection may have contributed to this pattern of HCV genotype distribution.
Project description:BACKGROUND: HCV transmission is closely associated with drug-trafficking routes in China. However, the transmission route of HCV in Eastern China remains unclear. Here, we investigate the role of Zhenjiang city of Jiangsu province, an important transportation hub linking Shanghai with other regions of China, in HCV transmission. METHODOLOGY/PRINCIPAL FINDINGS: A total of 141 whole blood samples were collected from injection drug users (IDUs) in Zhenjiang and then tested for HCV infection. Of them, 115 HCV positive plasmas were subjected to RNA extraction, RT-PCR amplification, and sequencing. The subtype characterization and the evolutionary origin of HCV strains circulating in Zhenjiang were determined using polygenetic or phylogeographic analyses. Seven HCV subtypes 1b, 2a, 3a, 3b, 6a, 6e and 6n were detected among Zhenjiang IDUs, showing a complex HCV epidemic. The most predominant subtypes were 3a (38%) and 1b (26.8%). Among these subtypes, subtypes 3b, 6n and 6e originated from Southwestern China (i.e., Yunnan and/or Guangxi), subtypes 2a and 6a from Southern China (i.e., Guangdong), subtype 1b from Central (i.e., Henan) and Northwestern (i.e., Xinjiang) China, and subtype 3a from Southwestern (i.e., Yunnan) and Northwestern (i.e., Xinjiang) China. From Zhenjiang, subtypes 1b and 2a were further spread to Eastern (i.e., Shanghai) and Northern (i.e., Beijing) China, respectively. CONCLUSIONS/SIGNIFICANCE: The mixing of seven HCV subtypes in Zhenjiang from all quarters of China indicates that as an important middle station, Zhenjiang plays a crucial role in HCV transmission, just as it is important in population migration between other regions of China and Eastern China.
Project description:Hepatitis C virus (HCV) genotype (GT) distribution in China shows significant geographical and demographic difference. As a routinely tested virus in Chinese blood bank systems, rare molecular epidemiology research in blood donors is reported. Our purpose is to investigate the HCV GT/subtypes distribution, phylogenetic analysis and population genetics in Chinese blood donors. Anti-HCV screen positive samples and donor demographics were collected. HCV Core and E1 gene fragments were amplified by RT-PCR, followed by sequencing and phylogenetic analysis to determine HCV GTs/subtypes using MEGA 7.0. The population genetics were performed using Arlequin v3.0 and Beast v1.10.4. SPSS Statistics 17.0 software was used to analyze the correlation between HCV GTs/subtypes distribution and demographic characteristics. 419 and 293 samples based on Core and E1 gene respectively were successfully amplified. HCV la, lb, 2a, 3a, 3b, 6a, 6e and 6n were found, and the corresponding proportions were 0.66% (3/455), 58.68% (267/455), 17.80% (81/455) and 5.05% (23/455), 3.52% (16/455), 12.31% (56/455), 0.88% (4/455) and 0.66% (3/455). Samples from Guangxi showed the most abundant genetic diversity with 8 subtypes were found. The number of haplotypes in HCV-1b is higher than 2a and 6a. The negative Tajima's D and Fu's Fs values of HCV-1b, 2a and 6a suggested the population expansion of those HCV subtypes. The distribution of HCV GT showed significant statistical difference by age and ethnicity. Conclusion: An abundance of HCV genetic diversity was found in Chinese blood donors with mainly 1b and then 2a subtype. There were significant geographical and demographic differences in HCV GTs/subtypes among Chinese blood donors. HCV subtype 1b has stronger viability and HCV subtype 6a has experienced significant expansion.
Project description:The global epidemiology of hepatitis C virus (HCV) may be roughly described by two groups of genotypes: the worldwide distributed ones (subtypes 1a, 1b, 2a and 3a, among others) and the endemic ones (subtypes 4a, 5a, 6a, among others). Epidemiological and population dynamic studies of the worldwide distributed genotypes have shown that subtypes 1a and 3a are common among intravenous drug users (IDUs) and that they are also in expansion in some countries. The molecular survey of HCV provides some clues about the epidemiological status of the infections in a local scale and the phylogenetic and demographic reconstruction analyses complement this study by inferring whether the infections of certain subtypes are in a steady state or expanding. Here, a molecular survey of the HCV variants that circulate in the touristic city of Mar del Plata (Buenos Aires, Argentina) was performed in samples obtained from 42 patients. The subtypes detected were 1a (32 patients), 3a (8 patients) and 1b (2 patients). The demographic history of subtype 1a inferred using the sequence data showed an exponential growth in the 1990's. The period of viral expansion was delayed compared with that observed for the same genotype in other countries where the transmission was associated with IDUs. Also, the phylogeographic analysis of HCV-1a showed a statistically significant association between the location of the samples and the phylogeny, which may be the result of the local transmission of HCV in the city. The molecular analysis helped in the description of the complex epidemiological context of a touristic city, and pointed out that some sanitary measures should be taken in order to reduce the transmission of HCV (and maybe of HIV) among IDUs.
Project description:The human immunodeficiency virus 1 (HIV-1) epidemic in China historically stemmed from intravenous drug users (IDUs) in Yunnan. Due to a shared transmission route, hepatitis C virus (HCV)/HIV-1 co-infection is common. Here, we investigated HCV genetic characteristics and baseline drug resistance among HIV-infected IDUs in Yunnan.Blood samples of 432 HIV-1/HCV co-infected IDUs were collected from January to June 2014 in six prefectures of Yunnan Province. Partial E1E2 and NS5B genes were sequenced. Phylogenetic, evolutionary and genotypic drug resistance analyses were performed.Among the 293 specimens successfully genotyped, seven subtypes were identified, including subtypes 3b (37.9%, 111/293), 3a (21.8%, 64/293), 6n (14.0%, 41/293), 1b (10.6%, 31/293), 1a (8.2%, 24/293), 6a (5.1%, 15/293) and 6u (2.4%, 7/293). The distribution of HCV subtypes was mostly related to geographic location. Subtypes 3b, 3a, and 6n were detected in all six prefectures, however, the other four subtypes were detected only in parts of the six prefectures. Phylogeographic analyses indicated that 6n, 1a and 6u originated in the western prefecture (Dehong) and spread eastward and showed genetic relatedness with those detected in Burmese. However, 6a originated in the southeast prefectures (Honghe and Wenshan) bordering Vietnam and was transmitted westward. These subtypes exhibited different evolutionary rates (between 4.35×10-4 and 2.38×10-3 substitutions site-1 year-1) and times of most recent common ancestor (tMRCA, between 1790.3 and 1994.6), suggesting that HCV was multiply introduced into Yunnan. Naturally occurring resistance-associated mutations (C316N, A421V, C445F, I482L, V494A, and V499A) to NS5B polymerase inhibitors were detected in direct-acting antivirals (DAAs)-naïve IDUs.This work reveals the temporal-spatial distribution of HCV subtypes and baseline HCV drug resistance among HIV-infected IDUs in Yunnan. The findings enhance our understanding of the characteristics and evolution of HCV in IDUs and are valuable for developing HCV prevention and management strategies for this population.