High prevalence of HIV-1 and hepatitis C virus coinfection among injection drug users in the southeastern region of Yunnan, China

Severity of drug dependence, economic pressure and HIV-related risk behaviors among non-institutionalized female injecting drug users who are also sex workers in China

BACKGROUND

Female injecting drug users (IDUs) who are also sex workers (FSW-IDUs) is an important bridge population transmitting HIV from the IDU population to clients of FSWs. Little is known about the relationships between severity of drug dependence, economic pressure and relevant HIV-related risk behaviors.

METHODS

281 non-institutionalized participants were recruited using snowball sampling methods. Anonymous face-to-face interviews were administered by trained doctors.

RESULTS

64.1% of participants used condoms inconsistently with their clients in the past 6 months; 28.5% served at least 2 clients per day and 48.4% practiced at least one of the three studied needle sharing behaviors. Severity of drug dependence (adjusted OR=1.05, p<0.01) and economic pressure (adjusted OR=1.07 to 2.52, p<0.05) were significantly associated with inconsistent condom use with clients in the last 6 months. Severity of drug dependence (adjusted OR=1.15, p<0.01) and variables related to perceived economic pressure (adjusted OR=1.09-3.05, p<0.05) were significantly associated with higher frequency of commercial sex transaction. Severity of drug dependence (adjusted OR=1.07, p<0.01) were also associated with needle sharing behaviors. In summary models, severity of drug dependence (OR=1.17, p<0.001), economic pressure (OR=1.39, p<0.001) and their interaction term (OR=0.98, p<0.001) were all associated with inconsistent condom use with clients in the last 6 months.

CONCLUSIONS

Prevalence of unprotected commercial sex was high and was independently associated with severity of drug dependence and economic pressure; severity of drug dependence was also associated with needle sharing behaviors. Such issues need to be fully considered when planning research studies and interventions.

Predictors of HIV infection and prevalence for syphilis infection among injection drug users in China: community-based surveys along major drug trafficking routes

Objective

To assess the predictors and prevalence of HIV infection among injection drug users in highly endemic regions along major drug trafficking routes in three Chinese provinces.

Methods

We enrolled participants using community outreach and peer referrals. uestionnaire-based interviews provided demographic, drug use, and sexual behavior information. HIV was tested via ELISA and syphilis by RPR.

Results

Of the 689 participants, 51.8% were HIV-infected, with persons living in Guangxi having significantly lower prevalence (16.4%) than those from Xinjiang and Yunnan (66.8% and 67.1%, respectively). Syphilis seropositivity was noted in 5.4%. Longer duration of IDU, greater awareness of HIV transmission routes, and living in Xinjiang or Yunnan were associated with HIV seropositivity on multivariable analysis. Independent risk factors differed between sites. In Guangxi, being male and having a longer duration of IDU were independent risk factors for HIV infection; in Xinjiang, older age and sharing needles and/or syringes were independent factors; in Yunnan, more frequent drug injection, greater awareness of HIV transmission routes, and higher income were independent predictors of HIV seropositivity.

Conclusion

Prevalence rates of HIV among IDUs in China are more than two out of three in some venues. Risk factors include longer duration of IDU and needle sharing. Also associated with HIV were factors that may indicate some success in education in higher risk persons, such as higher knowledge. A systemic community-level intervention with respect to evidenced-based, population-level interventions to stem the spread of HIV from IDU in China should include needle exchange, opiate agonist-based drug treatment, condom distribution along with promotion, and advocacy for community-based VCT with bridges to HIV preventive services and care.

Regional differences in HIV prevalence among drug users in China: potential for future spread of HIV?

Background

Drug use and in particular injecting drug use has been at the forefront of the explosive spread of HIV in general populations in many countries in Asia. There is concern that also in China increased HIV incidence in drug users might spark off a generalized epidemic in the wider population. Close monitoring of HIV incidence and risk factors in drug users is therefore important to be able to target interventions effectively. Second generation surveillance was launched to assess HIV prevalence and risk behaviours jointly with the purpose of describing trends and predicting future developments. To assess whether these goals were fulfilled among drug users in China we provide an analysis of risk factors for HIV infection and of regional differences in HIV prevalence.

Methods

We analysed data collected in 2005 in 21 drug user second generation surveillance sentinel sites from 14 provinces in China. We used random effects logistic regression to test for risk factors for HIV infection and regional differences.

Results

The overall HIV-1 antibody prevalence was 5.4% (279/5128); 4.9% among injecting drug users (IDU) not sharing needles and 3.7% among non-injecting drug users. We found substantial heterogeneity among the surveillance sites with prevalence rates ranging between 0% and 54%. HIV status was strongly affected by the regional prevalence of HIV. Risk behaviours were highly prevalent in regions where HIV prevalence is still low. The distribution of duration of drug use in different sites indicated different stages of the drug use epidemics.

Conclusion

]Regional differences in HIV prevalence in China reflect different stages of the drug use and HIV epidemics rather than differences in risk behaviours. Therefore, outbreaks of HIV among drug users in regions where prevalence is still low can be expected in the future. However, methodological limitations of surveillance embedded into routine systems limit the usability of existing data. More standardized approaches to data collection in secondary generation HIV surveillance are necessary to better understand regional differences in risk behaviour and prevalence and to design targeted intervention for those regions at risk of experiencing outbreaks.

The unique HCV genotype distribution and the discovery of a novel subtype 6u among IDUs co-infected with HIV-1 in Yunnan, China

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.

Genetic variation of hepatitis C virus in a cohort of injection heroin users in Wuhan, China

Since the majority of heroin abusers use injection as the primary route of admission, heroin abuse contributes significantly to the transmission of hepatitis C virus (HCV). We determined HCV infection and its genotype distribution among injection heroin users in Wuhan, the largest city in the central China. Eight hundred seventy-eight (84%) out of 1046 serum specimens from the injection drug users were positive for HCV antibody. Out of randomly selected 122 specimens positive for HCV antibody, seventy-eight (64%) had detectable HCV RNA with genotype 6a as the predominant strain (50%), followed by 3b (32.2%), 1a (8.1%), 1b (6.5%), and 3a (3.2%). HCV RNA levels in male heroin users were significantly higher (P=0.013) than those in the female subjects. Although there was no significant difference in HCV RNA levels among the specimens positive for HCV 6a and 1a/1b, the samples with 6a or 1a/1b contained higher levels of HCV RNA than the specimens positive for HCV 3b (P=0.019, P=0.012, respectively). These findings indicate that there is a high prevalence of HCV infection with genotypes 6a and 3b as predominated strains among injection heroin users in Wuhan, China.

Changes in the prevalence of HIV-related behaviors and perceptions among 1832 injecting drug users in Sichuan, China

OBJECTIVE

To evaluate overall effectiveness of human immunodeficiency virus-related prevention programs among injecting drug users in Sichuan, China.

DESIGN

Behavioral surveillance data were analyzed.

RESULTS

The coverage rates for various service types increased from 2002--2004. The prevalence of using other's used syringes in the last month decreased from between 24.7% and 54.1% in the baseline years (2002 or 2003) to between 11% and 18.9% in 2004 [odds ratio (OR) = 0.1, 95% confidence interval (CI): 0.06-0.2 to OR = 0.6, 95% CI: 0.4-0.9, P <0.05]. Improvements were observed in prevalence of giving used syringes to others for drug injection in the last month (OR = 0.1, 95% CI: 0.06-0.1 to OR = 0.7, 95% CI: 0.5-0.9 in 3 counties, P <0.05) etc. Increase in prevalence of condom use with commercial sex partners or nonregular partners were observed in 3 counties (2004 vs. baseline year: OR = 0.2, 95% CI: 0.1-0.5 to OR = 0.4, 95% CI: 0.2-0.9, P <0.05) but not for prevalence of condom use with regular sex partners.

CONCLUSION

The results supported the claim that harm reduction programs targeting injecting drug users have been effective.

Different sliding window sizes and inappropriate subtype references result in discordant mosaic maps and breakpoint locations of HIV-1 CRFs

Different sliding window sizes and inappropriate subtype references are often selected for identifying HIV-1 recombination, which results in discordant recombination maps even for the same HIV-1 recombinant and affects the tracking of the epidemic of HIV-1 recombinants. Here, we re-analyzed 11 previously characterized HIV-1 CRFs using SimPlot software (version 3.5) with several sliding window sizes (200, 250, 300, 350 and 400 nt), moving in a step of 10 nt, respectively. We found that the crossovers determined under 250 and 350 nt windows, especially under 300 nt window are significantly closer to hypothetical breakpoint than crossovers obtained under 200 and 400 nt windows (P < 0.01). These suggest that 300 nt window is a preferential selection for HIV-1 recombination analysis. In addition, instead of one bootscan analysis, three bootscanning plots with sliding window sizes of 250, 300 and 350 nt are also recommended. The comparison between crossovers determined under different moving steps showed that a small moving step (e.g. 10 nt) is better than a larger step (e.g. 50 nt) (P < 0.05), suggesting that a small moving step should be used in bootscan analysis. Moreover, we found that inappropriate usage of subtype references in bootscan analysis resulted in misleading recombination maps. HIV-1 strains prevailing in the same geographic areas with HIV-1 inter-subtype recombinants are believed to have chance to participate in recombination events. When HIV-1 reference strains from recombinant-prevailing areas were applied, identified recombination patterns were well supported by phylogenetic analyses. So, in bootscan analysis, HIV-1 subtype references should be selected from recombinant-prevailing areas.

Factors influencing a low rate of hepatitis C viral RNA clearance in heroin users from Southern China

AIM: To study the virological and host factors influencing hepatitis C infection outcomes in heroin users in southern China.

METHODS: HCV RNA and associated factors were analyzed among 347 heroin users from Guangxi Zhuang Autonomous Region, southern China who were hepatitis C virus (HCV) EIA positive for two or more consecutive visits.

RESULTS: Using the COBAS AMPLICOR HCV TEST, a remarkably low HCV RNA negative rate of 8.6% was detected. After multivariate logistic regression analysis, HCV RNA clearance was significantly associated with the presence of HBsAg (OR = 8.436, P < 0.0001), the lack of HIV-1 infection (OR = 0.256, P = 0.038) and age younger than 25 (OR = 0.400, P = 0.029).

CONCLUSION: Our study suggests HCV infection among Chinese heroin users results in high levels of viral persistence even amidst factors previously found to enhance viral clearance. Prospective studies of a possible genetic component within the Chinese population and the pathogenicity of non-genotype 1 HCV infections are needed.

Molecular epidemiology of human immunodeficiency virus type 1 and hepatitis C virus in former blood donors in central China

The prevalence of hepatitis C virus (HCV) among human immunodeficiency virus (HIV-1)-positive former blood donors (FBDs) in Hubei province, central China, and the subtypes of these two viruses are identified. HIV-1-positive specimens were collected from FBDs, transfusion recipients, and their sexual partners in Hubei province, central China. The prevalence of HCV in HIV-1-positive FBDs was 78.6%. The dominant circulating HIV-1 subtype of FBDs was subtype B' (Thai-B); one belonged to U.S.-European subtype B. HCV genotypes 2a (78.6%) and 1b (21.4%) were detected. No recombinant form of HIV-1 was identified. Non-B' subtypes occurring among FBDs indicate the complexity of the HIV-1 prevalence in central China, where HIV is beginning to spread into the general population.

Migration and transmission of blood-borne infections among injection drug users: understanding the epidemiologic bridge

Migration is one of many social factors contributing to the spread of HIV and other blood-borne or sexually transmitted infections (STI). Bringing together large numbers of people from diverse settings, the process of migration moves infected individuals to diverse geographic locations. Injection drug users (IDU) are a relatively mobile group, often moving between cities, smaller communities, and across international borders for reasons of work, security, or access to narcotics. This mobility indicates the potential for IDU who engage in risky behavior outside their home areas to transmit HIV infection to other IDU, their sex partners, and others in the population. The objectives of this review are to examine: (1) the influence of drug trafficking and the spread of drug use on the diffusion of HIV, (2) the influence of migration on drug use and HIV-related risk behaviors among migrants, and (3) the mobility patterns of IDU and its role in the spread of HIV. We also discuss the potential policy implications of addressing prevention and care issues in mobile drug using populations.

Efficient infection of tree shrew (Tupaia belangeri) with hepatitis C virus grown in cell culture or from patient plasma

The generation of a new, cost-effective, non-primate, small-animal model would greatly facilitate research into hepatitis C virus (HCV) pathogenesis and the development of novel therapeutic and preventative technologies to control the increasing HCV threat to public health. Native HCV from patient plasma and HCV grown in cell culture (HCVcc) were used to inoculate adult tree shrews. Each animal was inoculated with one HCV genotype. Alanine aminotransferase (ALT) levels, HCV RNA and viral load were determined in the animals before and after inoculation. For native HCV, 16/18 inoculated tree shrews (89 %) became infected; 12/16 (75 %) of these animals became chronically infected, whilst infection was resolved in the remaining four (25 %). For HCVcc, infection occurred in 10/12 inoculated tree shrews (83 %) and chronic infection was observed in two of these animals. HCVcc from Huh7 cells showed a higher infectivity than that from HeLa cells. The animals inoculated with inadequate amounts of HCV were not infected in either native HCV or HCVcc experiments. Peak viral loads reached 10(3)-10(5) international units ml(-1) in chronically infected animals. ALT level changes reflected the normal fluctuation range in most animals. Thus, tree shrews without immunosuppression can be infected efficiently by native HCV and HCVcc when the animal is inoculated with an adequate amount of single-genotype HCV.

Clustering of Syringe Sharing and Unprotected Sex Risk Behaviors in Male Injecting Drug Users in China

OBJECTIVES

To investigate, among male injecting drug users (IDU), the relationships between higher risk IDU-related and sex-related behaviors.

GOAL

To highlight the clustering effects of the 2 forms of risk behaviors.

STUDY DESIGN

Behavioral surveillance surveys conducted in Sichuan were analyzed (n = 3105).

RESULTS

Of all respondents, 35.7% had injected with others' used syringes in the last 6 months, which was associated with female sex workers (FSW) and nonregular sex partners (NRP) partnership (OR = 1.81 and 1.59 respectively), and having had unprotected sex with FSW, NRP, and regular sex partners (OR = 1.96, 1.57, and 1.38 respectively). Higher drug use frequency was associated with having unprotected sex with FSW (among client of FSW, OR = 1.7) and with NRP (among those with NRP, OR = 1.61). Giving used syringes to others for injection was also associated with unprotected sex with NRP (OR = 1.97).

CONCLUSIONS

Interventions are urgently required to reduce both IDU-related and sex-related risk behaviors among male IDU.

Novel heroin injection practices: implications for transmission of HIV and other bloodborne pathogens

BACKGROUND

This paper describes injection risk in an out-of-treatment population of young heroin users in Hanoi, Vietnam, including use of a soft-tissue portal known as a "cay ma" (injection sac).

METHODS

Data from a large cross-sectional survey (N=1270) are used to describe the prevalence of this practice and its association with disease. Additionally, data from an ethnographic substudy on injectors serve to elaborate injectors' rationales for this injection practice.

RESULTS

This practice was common in this sample, appearing soon after initiation of habitual injection. Injectors report that this allows rapid and reliable access to a vein; strategic advantages in a dense urban environment where rapid injection, typically in public settings, is necessary to avoid discovery or arrest. Additionally, this practice is believed to mitigate risk for vein damage from co-morbid promethazine hydrochloride injection.

CONCLUSIONS

This practice may draw lymphocytes to injection sites, thereby increasing risk for transmission of bloodborne pathogens. Structural and behavioral interventions are needed for young heroin users in Vietnam.

Ethnicity and risk factors in needle sharing among intravenous drug users in Sichuan Province, China

Combining survey and ethnographic data, this research examined differences in the risk factors associated with needle sharing amongst intravenous drug users (IDUs) in the Sichuan Province of China. A comparison was made between the province's majority Han population and its Yi minority. We developed a theoretical framework consisting of risk factors at the individual level (including risk factors such as lack of AIDS knowledge, low self-efficacy, and economic pressure), interpersonal level (having an IDU primary partner and lack of family support), and community level (social discrimination). The findings suggested that the Yi minority group was more socially disadvantaged and had a higher risk of contracting HIV than the Han group. Furthermore, the factors that put them at risk were different to those which affected the Han group. OLS regression results showed that, for Han IDUs, needle sharing was positively associated with having an IDU primary partner and with economic pressure. On the other hand, for the minority group, needle sharing was significantly associated with being male, AIDS knowledge, the lack of family support, and social discrimination. These findings highlight the need for HIV prevention work to target marginalized populations in China, such as ethnic minorities, and to tailor appropriate prevention strategies to meet the specific needs of different groups.

Significance of blood analysis in hemophiliacs co-infected with human immunodeficiency virus and hepatitis viruses

AIM: To study the effect of hepatitis virus infection on cirrhosis and liver function markers in HIV-infected hemophiliacs.

METHODS: We have analyzed the immunological, liver function and cirrhosis markers in a cohort of hemophiliacs co-infected with human immunodeficiency virus (HIV) and hepatitis viruses.

RESULTS: There was no difference in immunological markers among co-infected patients and patients infected with HIV only and those co-infected with one or more hepatitis virus. Although liver function and cirrhosis markers remained within a normal range, there was a worsening trend in all patients co-infected with hepatitis virus C (HCV), which was further exacerbated in the presence of additional infection with hepatitis virus B (HBV).

CONCLUSION: Co-infection with HIV, HBV and HCV leads to worsening of hyaluronic acid and liver function markers. Increases in serum hyaluronic acid may be suggestive of a predisposition to liver diseases.

Clinical care of the HIV-infected drug user

HIV/AIDS and chemical dependency, the latter often intertwined with mental illness, are complex, overlapping spheres that adversely influence each other and the overall clinical outcomes of the affected individual. Each disorder individually impact tens of millions of people adversely, with explosive epidemics described worldwide. This article addresses the adverse consequences of HIV/AIDS, drug injection, the secondary comorbidities of both, and the impact of immunosuppression on presentation of disease as well as approaches to managing the HIV-infected drug user.

Coinfection with HIV and hepatitis C virus among injection drug users in southern China

BACKGROUND

We sought to examine coinfection with human immunodeficiency virus (HIV) and hepatitis C virus (HCV) among injection drug users (IDUs) in Guangxi, China.

METHODS

A longitudinal cohort of IDUs (547 subjects) was established to study risk factors for bloodborne infections. At each visit, participants completed questionnaires defining demographic characteristics, patterns of drug use, and sexual behaviors. Blood samples were collected and analyzed for the presence and genotype of HIV and HCV.

RESULTS

Coinfection with HIV and HCV was found in 17.6% of the IDUs. HCV was present in 95.1% of HIV-positive and 70.4% of HIV-negative heroin users. The prevalence of HIV in HCV-positive and HCV-negative heroin users was 23.4% and 3.6%, respectively. Multivariate logistic regression analysis revealed that sexual activity during the past 6 months and duration of injection drug use were significantly associated with coinfection with HIV and HCV. The main circulating HCV genotypes included 6a (38%), 3b (37%), and 1a (19%), whereas genotypes 6e (4%), 3a (2%), and 1b (1%) were present in only a few IDUs. Multiple HCV genotypes were present at each study site and did not segregate by HIV status or subtype.

CONCLUSIONS

HCV is highly prevalent in IDUs throughout southern China. In Guangxi, HIV infections are the result of parenteral and sexual transmission, and, therefore, all IDUs are at high risk of coinfection with HIV and HCV. Molecular tracking of HCV may be a more sensitive predictor of the future spread of the HIV-1 epidemic than is HIV subtyping. This study emphasizes that, without implementation of injection prevention and primary substance abuse programs in China, the extent and effect of coinfection with HIV and HCV will only increase.

Differences in access to care among injection drug users infected either with HIV and hepatitis C or hepatitis C alone

Access to HCV (Hepatitis C virus) care for HIV/HCV-co-infected patients is an urgent public health concern. The objective of the present study was to describe the self-reported health status of HIV/HCV-co-infected and HCV-mono-infected injection drug users and to describe their access to HCV-related care. Beginning in May 1996, persons who had injected illicit drugs in the previous month were recruited into the Vancouver Injection Drug User Study (VIDUS). At baseline and then semi-annually, participants complete an interviewer-administered questionnaire. Blood is drawn at each semi-annual interview and tested for HIV and Hepatitis C infection. Data for this descriptive, cross-sectional study were drawn from the most recent of either the July 2003 or December 2003 nurse-administered questionnaire. Statistics used were the chi-square, Wilcoxon Rank Sum and Student's t-test. Logistic regression was used to examine factors independently associated with accessing HCV care. There were 707 individuals eligible for this analysis, including 240 HIV/HCV-co-infected and 467 HCV-mono-infected persons. Co-infected individuals were more likely to be female, younger, of Aboriginal ethnicity and less likely to use heroin daily. The HCV-mono-infected group tended to report higher rates of HCV-related symptoms, including fatigue, liver pain, nausea, night-sweats and stomach pain. However, it was the HIV/HCV-co-infected group who were more likely to report that they believed their hepatitis C was affecting them. The HIV/HCV-co-infected group were also more likely to report having received any hepatitis-related follow-up care, including blood work, liver biopsies and referrals to specialists. In logistic regression analysis, factors independently associated with ever receiving any hepatitis C related follow-up were HIV/HCV-co-infection (AOR 3.1; 95% CI: 2-4.7), being older (AOR 1.04; 95% CI: 1.02-1.06 per year older), using heroin daily (AOR 0.54; 95% CI: 0.36-0.82) and believing that hepatitis C was affecting one's health (AOR 1.4; 95% CI: 1.0-2.1). In conclusion, our data indicate more HCV healthcare utilization among those HIV/HCV-co-infected.

Molecular epidemiology of HIV type 1 subtypes in Taiwan: outbreak of HIV type 1 CRF07_BC infection in intravenous drug users

In Taiwan, sexual transmission is responsible for most HIV-1 infections with two dominant subtypes, subtype B and CRF01_AE, distributing among homosexual and heterosexual groups, respectively. Recently, intravenous drug use has become an emerging route of HIV-1 transmission and contributed to a significant increase of HIV-1 infection. To characterize the HIV isolates responsible for the outbreak among intravenous drug users (IDUs), phylogenetic analysis was performed to analyze the protease/RT sequences amplified from HIV-1-infected IDUs at National Taiwan University Hospital and Taipei City STD Control Center. CRF07_BC, which is circulating in northern China, was demonstrated to account for the majority of HIV-1 infection in IDUs in the past 2 years. Although these Taiwanese CRF07_BC sequences shared the same breakpoint positions as those described in the CRF07_BC reference sequences, they formed a unique cluster in the phylogenetic tree, suggesting they originated from a founder virus. This finding was further supported by the relative low genetic diversity and unique sequence features. Our results demonstrated the emergence of CRF07_BC and its association with the HIV-1 outbreak among IDUs between 2004 and 2005 in Taiwan. This finding not only helps us to have a better understanding of the HIV evolution in Asia, but also has important implications for vaccine design in the future.

Responding to AIDS, tuberculosis, malaria, and emerging infectious diseases in Burma: dilemmas of policy and practice

Beyrer and colleagues discuss infectious disease threats in Burma and suggest policy options for responding to them.

Complete genomic sequences for hepatitis C virus subtypes 6e and 6g isolated from Chinese patients with injection drug use and HIV-1 co-infection

In one of our recent studies, two HCV genotype 6 variants were identified in patients from Hong Kong and Guangxi in southern China, with injection drug use and HIV-1 co-infection. We report the complete genomic sequences for these two variants: GX004 and HK6554. Their entire genome lengths were 9,468 and 9,462 nt; the 5' UTRs were 338 nt followed by single ORFs of 9,069 nt; the 3' UTRs were 61 and 55 nt including 29 and 23 nt poly(U) tracks. Phylogenetic analysis using a maximum likelihood method showed that HK6554 was classified into subtype 6g and GX004 represented the first complete genome sequence for subtype 6e. Further analysis with reference sequences in three different genomic regions revealed that GX004 closely clustered with a group of subtype 6e variants, which were previously exclusively found in Vietnam and recently increasingly identified in injection drug users from the Guangxi province in southern China that borders Vietnam. This suggests that subtype 6e could become epidemic in southern China by network transmission among injection drug users.

HIV sexual risk behaviors among injection drug users in Shanghai

PURPOSE

This study investigated the sexual risk behaviors among injection drug users. (IDUs) in order to inform the development of sexual risk reduction interventions for IDUs.

METHODS

A cross-sectional survey of IDUs (n=141) was conducted in an in-patient detoxification treatment center in Shanghai, China, to collect information on demographics; drug use history; sexual risk behavior; HIV/AIDS knowledge, attitudes, and other psychosocial variables; and HIV, HBV, and HCV seroprevalence. Factors associated with HIV sexual risk behaviors and HBV and/or HCV infection were analyzed.

RESULTS

Sexual risk behaviors among IDUs were common: the majority (77%) of the participants had not used a condon consistently in the previous 3 months, 25.5% had multiple partners, 48.2% had IDU partners, and 75.9% did not know their partner's HIV status. IDUs who were married (OR=4.83, p<0.05) or did not intent to use condoms in the future (OR=0.21, p<0.05) were more likely to have unprotected sex. The prevalence of HBV and HCV infection was 31.9% and 51.8%, respectively, but no one tested positive for HIV.IDUs with an injection history of 3 years or more (OR=5.86, p<0.05) and with an overdose history (OR=3.21, p<0.05) were more likely to be infected with HBV and/or HCV.

CONCLUSIONS

Sexual risk behaviors among IDUs in Shanghai are common, and many IDUs are vulnerable for transmission of disease. Prevention efforts with IDUs should address sexual risk behaviors in addition to needle-sharing behaviors.

Population genetic history of hepatitis C virus 1b infection in China

Subtype 1b is the most common strain of Hepatitis C virus (HCV) in China. Here, the molecular epidemiology and epidemic history of this strain were investigated by conducting phylogenetic and population genetic analyses of E1 and NS5B gene sequences sampled from nine Chinese cities. The phylogenetic analysis indicated the presence of two clusters of Chinese strains that did not include reference strains from other countries, suggesting that these clusters represent two independent chains of HCV transmission within China. The remaining Chinese isolates were more closely related to reference strains from other countries. The date of origin and past population dynamics of the two groups were investigated using a new population genetic method, the Bayesian skyline plot. The estimated dates of origin of both groups coincide with the period of the Chinese 'Cultural Revolution' during the years 1966-1976. Both groups grew at a rapid exponential rate between approximately 1970 and approximately 1990, after which transmission slowed considerably. Possible explanations for the groups' fast spread and subsequent slowdown are discussed, including parenteral transmission by unsafe injection, iatrogenic transmission by infected blood or blood products and improvements in blood safety since 1990. These results shed light on HCV transmission in China and may help to predict the future burden of HCV-related disease in the country.

Hepatitis C coinfection is independently associated with decreased adherence to antiretroviral therapy in a population-based HIV cohort

OBJECTIVE

To characterize the impact of hepatitis C (HCV) serostatus on adherence to antiretroviral treatment (ART) among HIV-infected adults initiating ART.

METHODS

The British Columbia HIV/AIDS Drug Treatment Program distributes, at no cost, all ART in this Canadian province. Eligible individuals used triple combination ART as their first HIV therapy and had documented HCV serology. Statistical analyses used parametric and non-parametric methods, including multivariate logistic regression. The primary outcome was > or = 95% adherence, defined as receiving > or = 95% of prescription refills during the first year of antiretroviral therapy.

RESULTS

There were 1186 patients eligible for analysis, including 606 (51%) positive for HCV antibody and 580 (49%) who were negative. In adjusted analyses, adherence was independently associated with HCV seropositivity [adjusted odds ratio (AOR), 0.48; 95% confidence interval (CI), 0.23-0.97; P = 0.003], higher plasma albumin levels (AOR, 1.07; 95% CI, 1.01-1.12; P = 0.002) and male gender (AOR, 2.53; 95% CI, 1.04-6.15; P = 0.017), but not with injection drug use (IDU), age or other markers of liver injury. There was no evidence of an interaction between HCV and liver injury in adjusted analyses; comparing different strata of HCV and IDU confirmed that HCV was associated with poor adherence independent of IDU.

CONCLUSIONS

HCV-coinfected individuals and those with lower albumin are less likely to be adherent to their ART.

High risk populations and HIV-1 infection in China

China is currently experiencing one of the most rapidly expanding HIV epidemics in the world. Although the overall prevalence rate is still low, with a population of 1.3 billion, high-risk factors which have contributed to the HIV/AIDS epidemics worldwide continue to prevail in China, including a high rate of injecting drug use and needle sharing, commercial sex with low rates of condom use, and concurrent sex with both commercial sex workers and non-commercial casual or steady sex partners. In addition, there are increasing "double risk" populations overlapping drug users and sex workers, as well as increasing rates of STDs and HIV among high-risk populations. Sexual transmission, therefore, may serve as a bridge connecting high-risk populations with general populations. There is an urgent need to prevent the spread of HIV from these high-risk populations into the general population of China.

Prevalence and correlates of HIV risk behaviors among drug users in China

This study examined the prevalence and correlates of HIV risk behaviors among 1,153 current drug users in China. Chi-squared tests of differences were used to test if drug users differed from non-users; logistic regression was used to identify behavior-specific risk factors. Results indicate that 60% of drug users injected drugs and more than one third shared needles. Compared to non-users, drug users had higher rates of risky sexual behavior and HIV/STDs. Among drug users, ethnic minorities and migrants were most vulnerable to unprotected casual sex and needle sharing. Drug users who experienced social isolation were associated with lower odds of risk behaviors; those who had experiences of anti-social behaviors and commercial sex, poor HIV knowledge, and perceived greater vulnerability were more prone to unprotected casual sex and needle sharing. Additional correlates of unprotected casual sex included being single, depression, and taking drugs/alcohol during sex. Additional risk factors of needle sharing included education and initiated drug use at younger ages. It is imperative that HIV interventions in China target drug users and address behavior-specific risk factors.

Snapshot of HIV pathogenesis in China

Several reviews have focused on the nature of HIV infection and its spread in various geographical regions of China. In contrast, this review provides a comprehensive update on the prevalence of multiple HIV-1 subtypes, consequent emergence of recombinant and novel forms of HIV-1 in China, and the implications this may have on HIV diversity and the development of effective vaccines. In addition it also examines the dissemination of primary drug resistance in therapy naïve patients, as well as co-infections with two other important viruses-hepatitis B and C. The main purpose of this review is to provide a current snapshot of HIV-1 pathogenesis in China and possibly shed some light on the future of HIV evolution, and potential challenges for future vaccine and anti-retroviral therapeutics against HIV strains in this area.

The key role for local base order in the generation of multiple forms of China HIV-1 B'/C intersubtype recombinants

Background

HIV-1 is a retrovirus with high rate of recombination. Increasing experimental studies in vitro indicated that local hairpin structure of RNA was associated with recombination by favoring RT pausing and promoting strand transfer. A method to estimate the potential to form stem-loop structure by calculating the folding of randomized sequence difference (FORS-D) has been used to investigate the relationship between secondary structure and evolutionary pressure in some genome. It showed that gene regions under strong positive "Darwinian" selection were associated with positive FORS-D values. In the present study, the sequences of HIV-1 subtypes B' and C, both of which represent the parent strains of CRF07_BC, CRF08_BC and China URFs, were selected to investigate the relationship between natural recombination and secondary structure by calculating the FORS-D values.

Results

The apparent higher negative FORS-D value region appeared in the gag-pol gene region (nucleotide 0–3000) of HIV-1 subtypes B' and C. Thirteen (86.7 %) of 15 mosaic fragments and 17 (81 %) of 21 recombination breakpoints occurred in this higher negative FORS-D region. This strongly suggested that natural recombination did not occur randomly throughout the HIV genome, and that there might be preferred (or hot) regions or sites for recombination. The FORS-D analysis of breakpoints showed that most breakpoints of recombinants were located in regions with higher negative FORS-D values (P = 0.0053), and appeared to have a higher negative average FORS-D value than the whole genome (P = 0.0007). The regression analysis also indicated that FORS-D values correlated negatively with breakpoint overlap.

Conclusion

High negative FORS-D values represent high, base order determined stem-loop potentials and influence mainly the formation of stem-loop structures. Therefore, the present results suggested for the first time that occurrence of natural recombination was associated with high base order-determined stem-loop potential, and that local base order might play a key role in the initiation of natural recombination by favoring the formation of stable stem-loop structures.

Prevalence of hepatitis C in an ethnically diverse HIV-1-infected cohort in south London

OBJECTIVES

There is limited information on the prevalence of and risk factors for hepatitis C virus (HCV) infection among HIV-1-infected patients in the UK. Our objective was to determine the prevalence of HCV infection among an ethnically diverse cohort of HIV-infected patients in south London, and to extrapolate from these data the number of co-infected patients in the UK.

METHODS

A total of 1017 HIV-1-infected patients who had attended King's College Hospital HIV clinic between September 2000 and August 2002 were screened for HCV antibody using a commercial enzyme-linked immunosorbent assay (ELISA). Positive results were confirmed by polymerase chain reaction (PCR) or recombinant immunoblot assay. Demographic, clinical and laboratory data were obtained from the local computerized database and medical records. We applied our HCV prevalence rates in the different HIV transmission groups to the estimated number of HIV-infected persons in these groups in the UK, to obtain a national estimate of the level of HIV-HCV co-infection.

RESULTS

Of the 1017 HIV-1-infected patients, 407 (40%) were white men, 158 (15.5%) were black African men, 268 (26.3%) were black African women, and 61 (6%) and 26 (2.6%) were black Caribbean men and women, respectively. Heterosexual exposure was the most common route of HIV acquisition (53.5%), followed by men having sex with men (36.9%), and current or previous injecting drug use (IDU) (7.2%). The overall prevalence of HCV co-infection was 90/1017 (8.9%), but this varied substantially according to route of transmission, from 82.2% among those with a history of IDU (which accounted for 67% of all HCV infections), to 31.8% in those who had received blood products, to 3.5% and 1.8% in those with homosexually and heterosexually acquired infection, respectively. Multivariate logistic regression analysis identified several independent risk factors for HCV infection: a history of IDU [odds ratio (OR) = 107.2; 95% confidence interval (CI) = 38.5-298.4], having received blood products (OR = 16.5; 95% CI = 5.1-53.7), and either being from a white ethnic group (OR = 4.3; 95% CI = 1.5-12.0) or being born in Southern Europe (OR = 6.7; 95% CI = 1.5-30.7). Based on the 35,473 known HIV-1-infected persons in the UK and the 10 997 estimated to be unaware of their status, we projected that there are at least 4136 HIV-HCV co-infected individuals in the UK and 979 who are unaware of their status.

CONCLUSIONS

Overall, 9% of our cohort was HIV-HCV co-infected. The prevalence was highest among intravenous drug users (82%), who accounted for most of our HCV cases, and lowest among heterosexual men and women from sub-Saharan Africa and the Caribbean [< 2%]. Our estimate that a significant number of co-infected persons may be unaware of their HIV and HCV status, highlights an urgent need to increase the uptake of HCV and HIV testing, particularly among injecting drug users, to reduce the risk of onward transmission.

HIV infection among female drug users in Northern Thailand

Reports on HIV infection and risk behaviors among female drug users in developing countries, particularly in Asia, are limited. In this study, we investigated HIV prevalence and risk factors for HIV infection among 200 women admitted for 21-day inpatient drug detoxification in Chiang Mai, Thailand. Volunteers completed a face-to-face interview using a structured interview, HIV pre-test counseling, specimen collection for HIV and STD tests, and were provided test results and HIV post-test counseling 1 week later. Two-third of participants (68%) were ethnic minorities with no formal education. Overall, 14 (7%) were HIV positive: 25% among 28 heroin injectors and 4.1% among 172 opium or methamphetamine smokers (p<0.001). History of drug injection and sexual abuse were associated with HIV infection. HIV prevention strategies for drug-using women in Thailand should consider both harm reduction strategies for drug use and promoting safer sex measures in a culturally appropriate context.

Heterosexual Transmission of HIV in China: A Systematic Review of Behavioral Studies in the Past Two Decades

OBJECTIVE

The objective of this study was to address the role of heterosexual transmission of HIV in China.

GOAL

The goal of this study was to explore the prevalence of unsafe sex and the likelihood of HIV spread heterosexually from core populations to others.

STUDY

The authors conducted a review of behavioral studies.

RESULTS

Drug users were more likely to be involved in higher-risk sexual behaviors than were those who abstained from using drugs. Most female drug users (52-98%) reported having engaged in commercial sex. Most female sex workers (FSWs) and individuals with sexually transmitted diseases (STDs) had concurrent sexual partners. Many continued to have unprotected sex after noticing STD symptoms in themselves or their sexual partners. From 5% to 26% of rural-to-urban migrants had multiple sexual partners and 10% of males patronized FSWs during migration.

CONCLUSIONS

Factors such as high rates of FSW patronage, low rates of condom use during commercial sex, having sex with both commercial and noncommercial sexual partners, and high rates of STD infection may promote a heterosexual epidemic in China.

Characteristics and Sexually Transmitted Diseases of Male Rural Migrants in a Metropolitan Area of Eastern China

GOAL

The goal of this study was to identify the correlates and determine the prevalence of sexually transmitted diseases (STDs) among male rural migrants in Shanghai, China.

STUDY

The authors conducted a community-based cross-sectional study with an anonymous questionnaire interview and collection of blood and first-void urine samples for STD screening.

RESULTS

One thousand eighty-six (85.3%) of 1273 male rural migrants approached were interviewed. Among the 986 sexually active migrants, the prevalence of chlamydia, gonorrhea, and syphilis was 3.5%, 0.5%, and 1.0%, respectively. None were infected with HIV. The prevalence of STDs was 3.2% for construction workers, 5.6% for market vendors, and 5.6% for factory workers. Risk factors for STDs were longer duration in Shanghai, frequent hometown visits, having multiple sex partners, and the desire to have multiple sex partners.

CONCLUSIONS

The prevalence of STDs among male rural migrants is relatively low. Maintaining the current low prevalence can reduce the risk of an HIV epidemic among Shanghai migrants, but prevention messages need to be tailored to the low level of literacy in many migrants.

Surplus men, sex work, and the spread of HIV in China

While 70% of HIV positive individuals live in sub-Saharan Africa, it is widely believed that the future of the epidemic depends on the magnitude of HIV spread in India and China, the world's most populous countries. China's 1.3 billion people are in the midst of significant social transformation, which will impact future sexual disease transmission. Soon approximately 8.5 million 'surplus men', unmarried and disproportionately poor and migrant, will come of age in China's cities and rural areas. Meanwhile, many millions of Chinese sex workers appear to represent a broad range of prices, places, and related HIV risk behaviors. Using demographic and behavioral data, this paper describes the combined effect of sexual practices, sex work, and a true male surplus on HIV transmission. Alongside a rapid increase in sexually transmitted disease incidence across developed parts of urban China, surplus men could become a significant new HIV risk group. The anticipated high sexual risk among many surplus men and injecting drug use use among a subgroup of surplus men may create bridging populations from high to low risk individuals. Prevention strategies that emphasize traditional measures--condom promotion, sex education, medical training--must be reinforced by strategies which acknowledge surplus men and sex workers. Reform within female sex worker mandatory re-education centers and site specific interventions at construction sites, military areas, or unemployment centers may hold promise in curbing HIV/sexually transmitted infections. From a sociological perspective, we believe that surplus men and sex workers will have a profound effect on the future of HIV spread in China and on the success or failure of future interventions.

Clinical laboratory assessment of hepatitis C and HIV coinfected patients according to the antiretroviral therapy received

During the year of 2001, a retrospective, descriptive study in order to determine the influence of the antiretroviral therapy received by 111 HIV-HCV coinfected patients who had undergone at least one liver biopsy was conduced, 74 of them were treated with a protease inhibitor regimen (WPI), and 37 with a non-protease inhibitor regimen (NPI). The main characteristics found were: a young patient population (mean age 41 years old in both groups), composed in most part of male individuals (74.3% WPI and 51.4% NPI) with previous risk factors for both infections (WPI 93.2% and NPI 89.2%). The most significant findings included AIDS-defining disease (WPI 18.9% and NPI 13.5% of the cases), elevated hepatic enzyme levels (WPI: SGOT 52.1 and NPI 53.2), absence of liver disease-related symptoms (16.2% for both groups), average CD4 count > 350 for both groups (WPI 362.2 and NPI 378.1), predominantly low-grade fibrosis in both populations (0-2 in 63.6% of WPI patients and in 80% of NPI patients), with necro-inflammatory activity ranging from 5-7 in 51.3% and 42.9% of WPI patients and NPI patients, respectively. It is suggested a sequential biopsy to better evaluate the evolution of the hepatic disease, according to the HAART regimen received.

Community-Based Survey of HIV Transmission Modes Among Intravenous Drug Users in Sichuan, China

GOAL

The goal of this study was to investigate the prevalence and different transmission risk factors of HIV among intravenous drug users (IDUs) in the Liangshan Yizu Autonomous Region of Sichuan province, China.

METHODS

From November 8, 2002, to November 29, 2002, a community-based survey was conducted to investigate demographic characteristics, sharing patterns of injection equipment, frequencies of injection equipment, and sexual behaviors in IDUs. Blood samples were also collected to test for HIV and syphilis infection. A total of 379 subjects were recruited for the study through community outreach and peer recruiting methods.

RESULTS

Of 379 IDUs, HIV prevalence was 11.3% (43 of 379). Ethnicity, total times of shared injection equipment in the past 3 months, shared cotton in the past 3 months, and syphilis infection were associated with HIV infection after univariate analysis using the chi-squared test. Multivariate logistic regression analysis showed total times of sharing injection equipment in the past 3 months (odds ratio [OR], 2.28; 95% confidence interval [CI], 1.18-4.43) and syphilis infection (OR, 3.10; 95% CI, 1.48-6.48) in the final model were independently associated with HIV prevalence.

CONCLUSION

The results of this study suggested total times of sharing injection equipment in the past 3 months and syphilis infection were significantly associated with HIV infection. Further seroepidemiologic prospective cohort studies should be conducted to clarify the impact of syphilis and high-risk sexual behaviors on HIV transmission through unprotected sexual intercourse.

HIV/AIDS in Asia

HIV (ie, HIV-1) epidemics in Asia show great diversity, both in severity and timing. But epidemics in Asia are far from over and several countries including China, Indonesia, and Vietnam have growing epidemics. Several factors affect the rate and magnitude of growth of HIV prevalence, but two of the most important are the size of the sex worker population and the frequency with which commercial sex occurs. In view of the present state of knowledge, even countries with low prevalence of infection might still have epidemics affecting a small percentage of the population. Once HIV infection has become established, growing needs for care and treatment are unavoidable and even the so-called prevention-successful countries of Thailand and Cambodia are seeing burgeoning care needs. The manifestations of HIV disease in the region are discussed with the aim of identifying key issues in medical management and care of HIV/AIDS. In particular, issues relevant to developing appropriate highly active antiretroviral treatment programmes in the region are discussed. Although access to antiretroviral therapy is increasing globally, making it work effectively while simultaneously expanding prevention programmes to stem the flow of new infections remains a real challenge in Asia. Genuine political interest and commitment are essential foundations for success, demanding advocacy at all levels to drive policy, mobilise sufficient resources, and take effective action.

Community-based survey of HCV and HIV coinfection in injection drug abusers in Sichuan Province of China

AIM: To investigate the prevalence and risk factors of HCV/HIV coinfection in injection drug abusers (IDAs) in Lianshan Yi Autonomous Prefecture of Sichuan province, China.

METHODS: From November 8, 2002 to November 29, 2002, a community-based survey was conducted to investigate the demographic characteristics, patterns of shared injectors devices and sexual behaviors in IDAs. Blood samples were also collected to test HCV and HIV infection. A total of 379 subjects were recruited in the study through community outreach and peer recruiting methods.

RESULTS: Of the 379 IDAs, the HCV prevalence and HIV prevalence were 71.0% and 11.3%, respectively, and HCV/HIV coinfection was 11.3%. HCV infection was found in 100% and 67.3% of HIV-positive and HIV-negative IDAs, respectively. HIV prevalence was 16.0% in HCV positive IDAs while none of the HCV negative IDAs was positive for HIV. Ethnicity, shared needles or syringes and cotton in the past 3 mo and syphilis infection were associated with HCV/HIV coinfection shown by univariate analysis using chi-square test. Multivariate logistic regression analysis showed that shared needles or syringes in the past 3 mo (Odds ratio = 3.121, 95% CI: 1.278-7.617, P < 0.05) and syphilis infection (Odds ratio = 2.914, 95% CI: 1.327-6.398, P < 0.01) were significantly associated with HCV infection. No statistically significant association was found in univariate analysis between sexual behaviors and HCV/HIV coinfection.

CONCLUSION: Shared needles and syringes in the past 3 mo and syphilis infection were significantly associated with HCV infection. Further sero-epidemiological prospective cohort studies should be conducted to clarify the impact of syphilis and high risk sexual behaviors on HCV transmission through unprotected sexual intercourse.

Addressing the "risk environment" for injection drug users: the mysterious case of the missing cop

Ecological models of the determinants of health and the consequent importance of structural interventions have been widely accepted, but using these models in research and practice has been challenging. Examining the role of criminal law enforcement in the "risk environment" of injection drug users (IDUs) provides an opportunity to apply structural thinking to the health problems associated with drug use. This article reviews international evidence that laws and law enforcement practices influence IDU risk. It argues that more research is needed at four levels--laws; management of law enforcement agencies; knowledge, attitudes, beliefs, and practices of frontline officers; and attitudes and experiences of IDUs--and that such research can be the basis of interventions within law enforcement to enhance IDU health.

Characterization of HIV type 1 heterosexual transmission in Yunnan, China

The earliest HIV-1 epidemic in China started in Yunnan province, which continues to be one of the most severe areas affected. While HIV-1 infections are spreading rapidly among injection drug users (IDUs) in China, sexual transmission of HIV-1 has also been confirmed, threatening the general population. Recent survey data indicated that heterosexual transmission of HIV-1 in Yunnan was steadily increasing. Diverse HIV-1 strains, including subtype B, C, CRF01, and CRF08, are circulating among individuals who acquired HIV through sexual contacts. Multiple HIV-1 subtypes, including subtypes B, C, and CRF08, were also detected among IDUs. In comparison with other IDU cohorts, intersubject env sequence variation was much higher amongIDUs in Yunnan. Growing evidence suggests that unprotected sex continues to occur at high rates among IDUs and their sex partners. Intervention strategies are urgently needed to target individuals at high risk for HIV heterosexual transmission and injection drug use. The complex pattern of HIV-1 distribution in the high-risk populations in Yunnan may have important implications for HIV transmission as well as vaccine development and evaluation.

Human immunodeficiency virus in Uzbekistan: epidemiological and genetic analyses

This study investigates the molecular epidemiology of HIV in Uzbekistan--a former Soviet Union (FSU) country located in central Asia. A total of 18,910,370 subjects were involved in an HIV serological examination through a population survey conducted in 1987-2002. Rapid changes in epidemiological dynamics and transmission modes have been observed since 1999: incidence rose from 25 newly HIV-infected subjects per year to more than 100 new cases per month within the first half of 2002, and the rate of intravenous drug use (IVDU)-associated HIV infection increased to 75% per year during the same period. Thirty HIV-1 strains, isolated from specimens obtained in 1999-2000, were directly sequenced in the env region. Phylogenetic analysis revealed a relationship to genotype A in 56.7%, and to 03_CRFAB in 13.3%; both variants have been previously reported in the FSU. The majority (85.7%) of these strains were isolated from IVDUs. The demographic history of the most prevalent HIV strain in Uzbekistan was inferred from reconstructed molecular phylogenies; exponential growth of the viral population size was thus observed to occur after the mid-1990s. In summary, detectable HIV seroprevalence remains low in the general population of Uzbekistan. However, the current study demonstrates a substantially increasing number of new infections, in association with IVDU, and an exponentially growing effective population size of the IVDU-associated HIV strain.

Mix-infections with different genotypes of HCV and with HCV plus other hepatitis viruses in patients with hepatitis C in China

AIM

Clinical therapy and prognosis in HCV infections are not good, and mix-infections with different HCV genotypes or quasispecies and mix-infections with HCV plus other hepatitis viruses are important concerns worldwide. The present report describes the sequence diversity and genotying of the 5'NCR of HCV isolates from hepatitis patients mix-infected with different HCV genotypes or variants, and the conditions of mix-infections with HCV plus other hepatitis viruses, providing important diagnostic and prognostic information for more effective treatment of HCV infections.

METHODS

The 5' non-coding region (5'NCR) of HCV was isolated from the patients sera and sequenced, and sequence variability and genotypes of HCV were defined by nucleotide sequence alignment and phylogenetic analysis, and the patients mix-infected with HCV plus other hepatitis viruses were analyzed. The conditions and clinical significance of mix-infections with HCV plus other hepatitis viruses were further studied.

RESULTS

Twenty-four out of 43 patients with chronic hepatitis C were defined as mix-infected with different genotypes of HCV. Among these 24 patients, 9 were mix-infected with genotype 1 and 3, 7 with different variants of genotype 1, 2 with different variants of genotype 2, 6 with different variants of genotype 3. No patients were found mix-infected with genotype 1 and 2 or with genotype 2 and 3. The clinical virological analysis of 60 patients mix-infected with HCV plus other hepatitis viruses showed that 45.0 % of the patients were mix-infected with HCV plus HAV, 61.7 % with HCV plus HBV, 6.7 % with HCV plus HDV/HBV, 8.4 % with HCV plus HEV, 3.3 % with HCV plus HGV. Infections with HCV plus other hepatitis viruses may exacerbate the pathological lesion of the liver.

CONCLUSION

The findings in the present study imply that mix-infections with different HCV genotypes and mix-infections with HCV plus other hepatitis viruses were relatively high in Yunnan, China, providing important diagnostic and prognostic information for more effective treatment of HCV infections.

Identification and characterization of a new class of human immunodeficiency virus type 1 recombinants comprised of two circulating recombinant forms, CRF07_BC and CRF08_BC, in China

We identified a new class of human immunodeficiency virus type 1 (HIV-1) recombinants (00CN-HH069 and 00CN-HH086) in which further recombination occurred between two established circulating recombinant forms (CRFs). These two isolates were found among 57 HIV-1 samples from a cohort of injecting drug users in eastern Yunnan Province of China. Informative-site analysis in conjunction with bootscanning plots and exploratory tree analysis revealed that these two strains were closely related mosaics comprised of CRF07_BC and CRF08_BC, which are found in China. The genotype screening based on gag-reverse transcriptase sequences of 57 samples from eastern Yunnan identified 47 CRF08_BC specimens (82.5%), 5 CRF07_BC specimens (8.8%), and 3 additional specimens with the novel recombinant structure. These new "second-generation" recombinants thus constitute a substantial proportion (5 of 57; 8.8%) of HIV-1 strains in this population and may belong to a new but yet-undefined class of CRF. This might be the first example of CRFs recombining with each other, leading to the evolution of second-generation inter-CRF recombinants.