CRF07_BC is associated with slow HIV disease progression in Chinese patients.

HIV subtypes convey important epidemiological information and possibly influence the rate of disease progression. In this study, HIV disease progression in patients infected with CRF01_AE, CRF07_BC, and subtype B was compared in the largest HIV molecular epidemiology study ever done in China. A national data set of HIV pol sequences was assembled by pooling sequences from public databases and the Beijing HIV laboratory network. Logistic regression was used to assess factors associated with the risk of AIDS at diagnosis ([AIDSAD], defined as a CD4 count < 200 cells/µL) in patients with HIV subtype B, CRF01_AE, and CRF07_BC. Of the 20,663 sequences, 9,156 (44.3%) were CRF01_AE. CRF07_BC was responsible for 28.3% of infections, followed by B (13.9%). In multivariable analysis, the risk of AIDSAD differed significantly according to HIV subtype (OR for CRF07_BC vs. B: 0.46, 95% CI 0.39─0.53), age (OR for ≥ 65 years vs. < 18 years: 4.3 95% CI 1.81─11.8), and transmission risk groups (OR for men who have sex with men vs. heterosexuals: 0.67 95% CI 0.6─0.75). These findings suggest that HIV diversity in China is constantly evolving and gaining in complexity. CRF07_BC is less pathogenic than subtype B, while CRF01_AE is as pathogenic as B.

Characterization of subtypes and transmitted drug resistance strains of HIV among Beijing residents between 2001-2016.

BACKGROUND: Beijing is a national and international hub potentially containing a broad diversity of HIV variants. Previous studies on molecular epidemiology of HIV in Beijing pooled together samples from residents and non-residents. Pooling residents and non-residents has potentially introduced bias and undermined a good assessment and the intervention among the autochthonous population. Here, we aimed to define HIV subtype diversity and investigate the TDR in Beijing residents exclusively. METHODS: We analyzed the demographic, clinical, and virological data collected between 2001 and 2016 from residents in Beijing. A population-based sequencing of the HIV pol gene was carried out using plasma specimens. Phylogenetic analysis was performed in order to classify sequences into their corresponding subtypes using an automated subtyping tool, the Context-Based Modeling for Expeditious Typing (COMET). Furthermore, the drug resistance mutations were determined using the World Health Organization list for surveillance of TDR mutations. RESULTS: Data on TDR were available for 92% of 2,315 individuals with HIV infection, of whom 7.1% were women. The bioinformatic analysis of HIV strains from this study revealed that a combined 17 subtypes were circulating in Beijing, China between 2001 and 2016. The most common ones were CRF01_AE, CRF07_BC, and subtype B in Beijing during this period. The overall prevalence of TDR was 4.5% (95% confidence intervals[CI]: 3.6%-5.4%), with a declining trend over the period of spanning 2001 through 2016. In-depth class-specific analysis revealed that the prevalence of TDR for the nucleoside reverse-transcriptase inhibitors (NRTIs) was 1.0% (95% CI: 0.6-1.5), 0.9% (95% CI:0.6-1.4) for non-NRTIs and 2.8% (95% CI:2.1-3.5) for protease inhibitors. The prevalence of TDR was lower in individuals infected with the CRF07_BC HIV strain than those infected with CRF01_AE. CONCLUSIONS: Our data showed that the HIV epidemic in Beijing displayed a high genetic heterogeneity and a low and declining prevalence of TDR. In sharp contrast to Europe and North America, the declining trend of TDR between 2001 through 2016 was noticed while there was a widespread distribution of antiretroviral treatment in Beijing, China.

Transmitted HIV drug resistance among individuals with newly diagnosed HIV infection: a multicenter observational study.

OBJECTIVES: Fifteen years after the roll-out of antiretroviral treatment (ART) in China, there is limited information available on transmitted HIV drug resistance (TDR). This study aimed to characterize the epidemiology of TDR in China. DESIGN: We conducted a prospective cross-sectional observational study. METHODS: We analyzed the demographic, clinical, and virological data of individuals with newly diagnosed HIV infection using data from the Beijing HIV laboratory network collected between 2001 and 2017. We did population-based sequencing of the pol gene on plasma specimens and identified TDR mutations using the WHO list for surveillance of TDR mutations. RESULTS: Data on TDR were available for 91% of the 10 115 individuals with newly diagnosed HIV infection tested, of whom 19.2% were from rural areas. The overall prevalence of TDR was 4.1% [95% confidence interval (CI): 3.7-4.5%], with a declining trend over the period 2001-2017. In the multivariable analysis, the risk of TDR differed significantly according to sex [odds ratio (OR) for women vs. men: 0.41, 95% CI: 0.22-0.69, P = 0.002]; infection type (OR for CRF07_BC vs. CRF01_AE: 0.24, 95% CI: 0.16-0.36, P < 0.001); and sampling period (OR for 2009-2012 vs. 2001-2008: 0.57, 95% CI: 0.41-0.79; P = 0.01), and was significantly higher among individuals from Hebei province than in those from Beijing (OR: 1.43, 95% CI: 1.05-1.96; P = 0.02). CONCLUSION: In China, the prevalence of TDR among individuals with newly diagnosed HIV infection is relatively low. Trends in TDR should be assessed in other countries with a high TDR burden.

Identification of a Novel HIV-1 Second-Generation Recombinant Form (CRF01_AE/07_BC) in Men Who Have Sex with Men in Beijing, China.

HIV-1 CRF01_AE and CRF07_BC have been two mainly circulating HIV-1 strains in the men who have sex with men (MSM) population in Beijing for years. These two subtypes together were accounting for 78.1% of HIV-1 positive cases newly diagnosed in Beijing, 2016. In this study, we report a novel CRF01_AE/CRF07_BC second-generation unique recombinant form (URF) (named DT1427_NFLG) of HIV-1 identified in MSM population. The near full-length genome of DT1427_NFLG is about 8.8 kb with four CRF07_BC fragments inserted into the CRF01_AE backbone. In China, several novel second-generation URFs were reported in recent years and Beijing, as the capital of China, attracting a huge number of people all over the country to work and live, is confronted with the risk of the epidemic of recombinant HIV-1 strains. Therefore, it is necessary to take measures to monitor the emergency of novel recombinant of HIV-1.

Trends of HIV incidence and prevalence among men who have sex with men in Beijing, China: Nine consecutive cross-sectional surveys, 2008-2016.

BACKGROUND: Sexual transmission of HIV among men who have sex with men (MSM) increased markedly in China during the past decade. HIV incidence is a critical indicator in HIV surveillance and we use a HIV-1 BED-capture-enzyme immunoassay (BED-CEIA) to examine the incidence among MSM in Beijing from 2008 to 2016. Risk factors related to recent HIV infection were also assessed. METHODS: Consecutive cross-sectional surveys on MSM were conducted yearly from 2008 through 2016. Demographic and behaviors data were collected. HIV status was determined and HIV positive specimens were tested for recent infection using BED-CEIA. Specimens with ODn values≤0.8 were considered recently infected, HIV incidence rates and prevalence were then calculated. Risk factors associated with recent HIV infection were assessed by univariate and multivariable logistic regression. RESULTS: From 2008 to 2016, the numbers of eligible participants in the nine consecutive years ranged from 472 to 616. All the 261 eligible HIV-positive specimens were subjected to recent HIV infection testing. HIV prevalence ranged from 5.0% (3.3%-6.8%) to 10.2% (7.8%-12.7%), and incidence ranged from 1.57% (0.19%-2.95%) to 6.63% (3.65%-9.61%). MSM who never or sometimes used condoms during anal sex with men in the past 6 months (aOR = 1.515, 95%CI: 1.016-2.257, p = 0.041), or having syphilis infection (aOR = 1.561, 95%CI: 0.946-2.575, p = 0.081) were more likely to be recently infected with HIV. Being a Beijing resident (aOR = 0.409, 95%CI: 0.212-0.790, p = 0.008), or having only one male anal sex partner in the past 6 months (aOR = 0.467, 95%CI: 0.220-0.994, p = 0.048) were associated with a lower risk for recent HIV infection. CONCLUSIONS: The HIV incidence fluctuated among MSM in Beijing. Unprotected anal sex, having multiple sex partners, being a non-registered Beijing resident and having a syphilis infection play important roles in the recent HIV infection. Effective intervention measures for HIV and syphilis control and prevention should be continuously strengthened.

A Unique Second-Generation Recombinant Form of HIV-1 Identified Among Men Who Have Sex with Men Population in Beijing, China.

In China, CRF01_AE and CRF07_BC are the most circulating strains of HIV-1, more and more second-generation recombinant forms have been isolated around the two strains. The same situation happened in Beijing in recent years. In our study, we have isolated a new second-generation recombinant form of HIV-1 from a male patient who was infected by homosexual behavior. Polygenetic analysis revealed that the sequence includes five CRF01_AE fragments and four CRF07_BC fragments. CRF01_AE is the skeleton of the recombinant which was inserted with four CRF07_BC fragments. The emergency of such second-generation recombinant forms manifests the diversity of the HIV-1 epidemic. Consequently, further investigation of molecular epidemiology is needed to track the genetic evolution of HIV-1.

Low Rates of Transmitted Drug Resistances Among Treatment-Naive HIV-1-infected Students in Beijing, China.

Beijing has seen a rising epidemic of HIV among students. However, little information was known about the molecular epidemiologic data among HIV-infected students. In this study, the diversity and the prevalence of transmitted drug resistance (TDR) in pol sequences derived from 237 HIV-infected students were analyzed. TDR mutations were found in five men who have sex with men (MSM) population among students. The overall prevalence of TDR in students was 2.1%, comprising 1.3% of protease inhibitors and 0.8% of non-nucleoside reverse transcriptase inhibitors. Our finding indicates a low-level prevalence of TDR mutations among students in Beijing.

[Analysis on factors associated with taking subsequent confirmation test among men who have sex with men after being tested positive in oral fluid HIV antibody test in Beijing].

OBJECTIVE: To analyze the proportion and associated factors of taking subsequent confirmation test among men who have sex with men (MSM) after being tested positive in oral fluid HIV antibody test. METHODS: By using successive sampling, 1 003 MSM, who were tested positive in oral fluid HIV antibody test in China-Bill & Melinda Gates Foundation AIDS prevention Program (Extension program) in Beijing during May 1 to December 31, 2013, were recruited. The inclusion criteria included: the objects were men who reported having sex with men; the objects aged more than 18 years old; the objects were tested positive in oral fluid HIV antibody test; the objects had not been reported as HIV positives in China Information System for Disease Control and Prevention previously. According to the program strategy, MSM grassroots organizations transferred the respondents to seek subsequent confirmation tests in specific Center for Disease Control and Prevention (CDCs) or hospitals. The subsequent confirmation tests included: fingertip blood HIV antibody rapid test, venous blood Enzyme Linked Immunosorbent Assay (ELISA) HIV antibody test and venous blood Western Blot (WB) HIV antibody test. Chi-square test was adopted to compare the proportion of taking subsequent confirmation tests in different groups. Nonconditional multivaritae binarylogistic regression analysis was taken to identify the associated factors with whether taking subsequent confirmation tests and to calculate the OR (95% CI) values. RESULTS: The 1 003 respondents were (30.9 ± 9.1) years old. Among all objects, 87.8% (881/1 003) of them took fingertip blood HIV antibody rapid tests and the positive rate was 85.4% (752/881). 98.0% (737/752) of those who were identified as positive in fingertip blood HIV rapid tests took ELISA and WB tests, and the positive rate was 94.4% (696/737). Comparing with those who were expected to seek subsequent confirmation tests in CDCs, the OR (95% CI) value of those who were expected to seek tests in hospitals was 5.10 (1.69-15.36). The OR (95% CI) values of those who used condom sometimes and those who never used condom in anal sex were 5.81 (2.14-15.77) and 3.45 (2.00-5.97) respectively, in comparison with those who reported not having anal sex or using condom consistently in anal sex during the past 6 months. Comparing with the respondents recruited from the internet, the OR (95% CI) values of those recruited in bathrooms, parks/toilets and bars were 0.17 (0.05-0.53), 0.10 (0.04-0.29) and 0.22 (0.06-0.79) respectively. The likelihood of taking subsequent confirmation test decreased with the increase of number of male sexual partners in the past 3 months, and the OR (95% CI) value was 0.92 (0.86-0.99). CONCLUSION: The potential HIV positive MSM in the bathroom, park/toilet and bars are less likely to take subsequent confirmation test. Those who do not use condom consistently during anal sex are more likely to seek subsequent confirmation test. Medical organization conducting subsequent confirmation tests is more likely to increase the confirmation test rate of potential HIV positive MSM. The number of male sexual partners has negative correlation with whether to accept the subsequent confirmation test.

[Molecular epidemiological characteristics of HIV-1 strains isolated from newly diagnosed MSM subjects (2006-2010) in Beijing, China].

This study aims to analyze the molecular epidemiological characteristics of HIV-1 strains prevailing among men who have sex with men (MSM) in Beijing, China. The pol gene fragments from 250 newly diagnosed HIV-1-infected MSM individuals during 2006-2010 in Beijing were amplified by RT-nested PCR, sequenced, and phylogenetically analyzed. HIV-1 pol gene from 189 individuals were amplified and analyzed; 81 (42. 9%), 3 (1. 6%), 2 (1.0%), 88 (46. 6%), and 15 (7.9%) individuals were infected with HIV-1 subtypes B, B', C, CRF01_AE, and CRF07_BC, respectively. The subtypes B and CRF01_AE could both be grouped into two clusters, and CRFO7_BC strains shared high homology and were presumed to originate from a common ancestor. The HIV-1 circulating in MSM in Beijing had a lower genetic diversity than in heterosexuals. The HIV-1 epidemic (2006-2010) in MSM in Beijing was actually a rapid spread of HIV-1 CRF01 AE and B, or rather native strains of the two viruses.

[Epidemiological analysis on recent infected HIV-1 patients among newly reported HIV cases in Beijing, from 2009 to 2011].

OBJECTIVE: To understand the epidemiologic characteristics on newly reported HIV cases and those recently infected HIV-1 cases in the past few years in Beijing so as to find out their correlates. METHODS: All the qualified newly reported HIV serum samples from both the first quarters of 2009, 2010 and the second quarter of 2011 in Beijing, were tested using the BED HIV-1 incidence capture enzyme immunoassay (BED-CEIA) to identify those recent HIV-1 infection (BED positive) samples and related socio-demographic characteristics. The proportions of BED positives were determined and the correlates analyzed by SPSS software. RESULTS: The Annual qualified newly reported HIV serum samples of each year from Beijing were 274, 236 and 356, with BED positive rate among them as 35.0%, 31.8% and 33.7%, respectively. The majority of newly reported HIV cases of each year were males (89.1%, 88.6%, 91.9%), range of age as 20-39 years (77.4%, 75.8%, 82.0%), Han nationality (77.7%, 88.6%, 85.7%), and most of them were not permanent residents of Beijing (74.1%, 80.5%, 2011 data missed). The proportions of patients through sexual transmission showed upward trend (67.5%, 76.2%, 86.8%). Especially in the 'man having sex with man' (MSM)group, it showed a significantly increase (44.9% , 45.3% , 62.6%). The proportions of injection drug users (15.3%, 8.1%, 9.0%)declined to some extent during this period. Data from statistics indicated that the proportions of BED positives among newly reported HIV cases of each year were significantly correlated to factors as patients' sex, transmission route and source of samples, but not significantly correlated to patents' age or marital status. Male cases accounted for 96.9% and MSM accounted for 73.5% of all the BED-positives during 2009-2011. CONCLUSION: MSM accounted for both large portion of newly reported HIV cases and recent HIV-1 infections which suggested an increasing trend in 2009-2011. It seemed that the characteristic and changing trends of HIV epidemic in Beijing was oriented by MSM population in the last years.

[Molecular epidemiological characteristics of HIV-1 B'/C strains in Beijing].

OBJECTIVE: To analyze the molecular epidemiological characteristic of HIV-1 B'/C strains prevalent in Beijing. METHODS: Plasma samples were collected from 200 newly diagnosed HIV-1 B'/C individuals reported during 2006 to 2010 in Beijing. The gag gene fragments were amplified from RNA template extracted from plasma with reverse transcription (RT) and nested polymerase chain reaction (PCR). And the sequences were analyzed by phylogenetic methods and Entropy analysis. RESULTS: A total of 159 sequences were successfully amplified from the gag genes of which 147 was CRF07_BC and 12 CRF08_BC. There were 3 main sub-clusters in CRF07_BC phylogenetic tree and they were named as sub-cluster IDU-Max (89 sequences), sub-cluster IDU-Min (22 sequences) and sub-cluster MSM (34 sequences) based on transmission.No international reference strain was closely related with these three sub-clusters except for one strain identified in Taiwan. All CRF07_BC recombinant strains were remarkable for their low interpatient diversity in gag genes (3.7%, 3.3% and 2.0% for isolates from IDU-Max, IDU-Min and MSM respectively).When compared with sub-cluster IDU-Max, there were 32 and 41 significantly different sites of nucleotide polymorphism compositions in sub-clusters IDU-Min and MSM. CONCLUSION: This is the first report of describing the existence of three main epidemic sub-clusters in CRF07_BC strains prevalent in Beijing. And IDU-Max sub-cluster is the dominant strain. The CRF07_BC in Beijing are less diverse than other strains and may be derived from a common ancestor.

[The high expression of HPV31 and 52 L2 fusion protein in E. coli and detection of its immunogenicity].

OBJECTIVE: To express HPV31 and 52 L2 fusion protein and detect its immunogenicity. METHODS: According to the amino acid sequences of HPV31 and 52 L2 11-200AA published in the GenBank database, weartificially synthesized the HPV31 and 52 L2 fusion gene which was optimized according to Escherichia coli codon usage and encodes 11-200 amino acid of HPV31 and HPV52 L2, then cloned it into pET-9a vector. The HPV31 and 52 L2 fusion protein was expressed in Prokaryotic expression system and the mice were immunized with the fusion protein after purification. The immunogenicity was characterized in vaccinated mice. RESULTS: HPV31 and 52 L2 fusion protein was highly expressed in E. coli, the amount of fusion protein is nearly 20% of the total bacterial protein. The purified fusion protein with aluminum adjuvant could induce specific high titer of IgG antibodies detected by ELISA, and also induce the neutralizing antibodies against pseudovirus of HPV31 and HPV52 and cross-neutralizing antibodies against pseudovirus of HPV45, 58, 16, 18. CONCLUSION: HPV31 and 52 L2 fusion protein could induce neutralizing and cross-neutralizing antibodies against HPV pseudovirus. It provides laboratory basis for development of HPV L2 protein vaccine.

[Molecular-epidemiological characteristics of HIV-1 isolated from newly diagnosed female subjects in Beijing, 2006 - 2010].

OBJECTIVE: To analyze the molecular-epidemiological characteristics of HIV-1 strains prevailing among female people living with HIV in Beijing. METHODS: Gag gene fragments from the 100 newly diagnosed female HIV-1 infections during 2006 to 2010 in Beijing were amplified, sequenced, and phylogenetically analyzed. RESULTS: Eighty-two HIV-1 gag gene fragments were amplified and analyzed. 1 (1.22%), 1 (1.22%), 3 (3.66%), 23 (28.05%), 8 (9.76%), 2 (2.44%), 1 (1.22%), 18 (21.95%), 3 (3.66%), 1 (1.22%), 14 (17.07%), 4 (4.88%) and 3 (3.66%) individuals were infected with HIV-1 subtypes A1, A2, B, B', C, D, G, H, CRF01_AE, CRF02_AG, CRF07_BC, CRF08_BC and B'/C recombinants respectively. CONCLUSION: The subtypes circulating in female HIV infections in Beijing were more diverse than in male and the proportions of B' and rare subtypes were relatively high. Surveillance programs on HIV-1 genetic diversity should be strengthened.