Search

To evaluate the impact of the CD4 count on ESAT6-CFP10 (EC) skin test, QuantiFERON-TB Gold In-tube test (QFT) and tuberculin skin test (TST) in a large prison and communities in Jiangsu Province among people living with HIV (PLHIV). Participants in communities were tested with the QFT and EC skin test and in prison were tested with the QFT, TST and EC skin test. A 4-knotted restricted cubic spline fitted for Logistic models was used to explore the cutoff point of CD4 count and the associations between changes in CD4 count and Mycobacterium tuberculosis (M.tb) infection. Among 1,815 PLHIV included, 19.3% (350) were from prisons and 80.7% (1465) were identified through community screenings. M.tb infection rates were 12.2% and 8.3% through QFT and EC tests, respectively. Odd Ratios (ORs) for infection increased with CD4 counts, peaking at 618 cells/mm 3 for EC, 392 cells/mm 3 for QFT, then plateaued. However, the pattern differed for EC between prison and screening scenarios. In prison settings, M.tb infection increased with CD4 count from 0 to 350 cells/mm3, plateaued until 500 cells/mm 3 , and then persistently increased. Conversely, for community, ORs decreased until 300 cells/mm 3 , followed by an increase between 300 and 729 cells/mm 3 , after which they continued to rise persistently. Our cross-sectional study among PLHIV revealed a higher rate of M.tb infection in prison compared to the community. The relationship between CD4 count and infection became negative after a certain threshold. This pivotal point differed with detection methods, with QFT showing lower CD4 thresholds than EC., (© 2024. The Author(s).)

Next-generation sequencing (NGS) for HIV drug resistance (DR) testing has an increasing number of applications for the detection of low-abundance drug-resistant variants (LA-DRVs) in regard to its features as a quasi-species. However, there is less information on its detection performance in DR detection with NGS. To determine the feasibility of using NGS technology in LA-DRV detection for HIV-1 pretreatment drug resistance, 80 HIV-infected individuals who had never undergone antiretroviral therapy were subjected to both NGS and Sanger sequencing (SS) in HIV-1 drug resistance testing. The results reported in this study show that NGS exhibits higher sensitivity for drug resistance identification than SS at a 5% detection threshold. NGS showed a better consistency compared with that of SS for both protease inhibitors (PIs) and integrase inhibitors (INSTIs), with a figure amounting to more than 90%, but worse consistency in nucleotide reverse transcriptase inhibitors (NRTIs), with a consistency ranging from only 61.25% to 87.50%. The consistency of non-nucleotide reverse transcriptase inhibitors (NNRTIs) between NGS and SS was around 85%. NGS showed the highest sensitivity of 87.0% at a 5% threshold. The application of NGS technology in HIV-1 genotype resistance detection in different populations infected with HIV requires further documentation and validation.

Objective: This meta-analysis aims to evaluate the global prevalence of mental disorders among young people living with HIV., Methods: A comprehensive search was conducted of the PubMed, Embase, and Cochrane Library databases for articles relevant to the study, published between January 2013 and June 2023. To identify sources of heterogeneity and compare prevalence estimates among various groups, subgroup analyses were conducted. Study heterogeneity was assessed using Cochran's Q and the I 2 tests. The robustness of the findings was ascertained through sensitivity analyses, while publication bias was evaluated with funnel plots and Egger's test., Results: Sixty studies were included in this meta-analysis. It revealed that approximately one-quarter of YLWH experience depression, with a prevalence of 24.6% (95% CI: 21.1-28.2%). The prevalence of anxiety was found to be 17.0% (95% CI: 11.4-22.6%). Regarding suicidality, the prevalence of suicidal ideation and lifetime suicidal ideation in YLWH was 16.8% (95% CI: 11.3-22.4%) and 29.7% (95% CI: 23.7-35.7%), respectively. Additionally, the prevalence rates for suicidal attempts and lifetime suicidal attempts were 9.7% (95% CI: 4.0-15.4%) and 12.9% (95% CI: 2.8-23.1%), respectively. The prevalence of Post-Traumatic Stress Disorder and Attention Deficit Hyperactivity Disorder was identified as 10.5% (95% CI: 5.8-15.2%) and 5.0% (95% CI: 3.1-7.0%), respectively., Conclusion: The findings indicate a heightened risk of mental disorders among YLWH, underscoring the necessity for targeted intervention strategies to mitigate their suffering and potentially diminish the adverse impacts., Systematic Review Registration: PROSPERO, identifier CRD42023470050, https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42023470050., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Zhan, Ouyang, Zhai and Yang.)

Recent global guidelines recommend Mycobacterium tuberculosis antigen-based skin tests, such as the ESAT6-CFP10 (EC) skin test, as acceptable alternatives to the tuberculin skin test (TST) and the QuantiFERON-TB Gold In-Tube test (QFT). However, the diagnostic value of these tests among persons living with HIV (PLHIV) is unknown. We aimed to assess the diagnostic accuracy of the EC among a cohort of PLHIV in China. We recruited PLHIV in Jiangsu Province, China, to assess sensitivity and specificity of the EC test. Participants were tested with the QFT, TST, and EC skin test. Results were stratified by age, M. tuberculosis BCG vaccination, and CD4 count. The sensitivity and specificity of the EC skin test was assessed using distinct cutoffs of the QFT and TST. Of 350 PLHIV enrolled in the study, 58 (16.6%), 89 (25.4%), and 59 (16.9%) tested positive with the EC test, the QFT, and the TST, respectively. Positivity increased with CD4 count; however, these trends were similar across tests. At a 5-mm cutoff, EC skin test specificity was high (99.6%, 95% confidence interval [CI] 95% CI = 97.7 to 100.0); however, sensitivity was moderate (81.4%; 95% CI = 66.6 to 91.6). After stratifying by BCG, the sensitivity and specificity were 86.4% (95% CI = 65.1 to 97.1) and 99.1% (95% CI = 95.0 to 100.0) among vaccinated PLHIV and 76.2% (95% CI = 52.8 to 91.8) and 100.0% (95% CI = 97.2 to 100.0) among unvaccinated PLHIV, respectively. Among PLHIV, the diagnostic value of the EC skin test remained high, regardless of BCG vaccination or CD4 count. The EC skin test performed comparably to TST and may be a valid alternative diagnostic test to use in settings or populations with high HIV prevalence and BCG vaccination. To our knowledge, this is the first study to evaluate the novel ESAT6-CFP10 skin test among PLHIV. Among 350 PLHIV, the test displayed high specificity and sensitivity, a finding which did not markedly differ based on BCG vaccination and CD4 count.

Objective: To analyze the latent tuberculosis infection (LTBI) among persons living with HIV(PLWH) in Jiangsu Province, to explore the factors affecting the positive rate of LTBI, and to take appropriate measures to control tuberculosis (TB) infection., Methods: A cross-sectional study was conducted among PLWH in Jiangsu Province from June to July 2021. All PLWH in Jiangsu Province were used as the study population. Currently, the diagnosis of LTBI lacks a "gold standard" and can only be assisted by the immunological method. In this study, Tuberculin skin test (TST), ESAT6-CFP10 test (EC), and QuantiFERON-TB gold in-tube (QFT) were used to detect the positive rate of LTBI among PLWH and to analyze their risk factors., Results: A total of 340 prisoners were included, 89.7% were male, the median age was 38 years [Interquartile Range (IQR):32-46 years], these patients were on Antiviral Therapy (ART), and median CD4 counts was 376 (IQR: 261-496), 103 (30.3%) were positive in at least one test, LTBI by TST was 16.5%, LTBI by EC was 15.9%, LTBI by QFT was 26.2%. Univariate analysis showed the results for TST, EC, and QFT were not affected by CD4 counts (p>0.05), and multivariate analysis showed that a history of incarceration was associated with an increased risk of positive TST (adjusted odds ratio [aOR]=1.98;95% CI,1.03-3.82), EC (aOR=2.65;95% CI,1.37-5.12) and QFT (aOR=2.01;95%CI,1.12-3.57), in addition, female gender was associated with increased risk of positive TST (aOR=3.66;95%CI,1.60-8.37) and EC (aOR=3.43;95%CI,1.46-8.07), and contact history of TB patients was associated with increased risk of TST (aOR= 2.54;95%CI,1.23-5.22) and QFT (aOR=2.03;95%CI,1.03-3.99), and ethnic minorities (aOR=0.26;95%CI,0.12-0.57), longer duration of incarceration was associated with an increased risk of positive QFT (aOR=1.12;95%CI,1.02-1.24). Conclusions Female gender, and ethnic minorities, history of incarceration, longer duration of incarceration, and contact history of TB patients are risk factors for LTBI among PLWH in Jiangsu Province, and attention should be paid to TB control in this population., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Zhang, Lu, Wu, Zhou, Yu, Yuan, Dong, Liu, Lu, Yang, Cao and Zhu.)

Background: The World Health Organization has recommended HIV self-testing (HIVST) as an alternative testing strategy given the limitations of facility-based testing. While the benefits of HIV self-testing have been demonstrated at the individual level among men who have sex with men (MSM), limited data exist on if this testing approach can be effectively diffused through individuals' social or sexual networks. The objectives of this study were to examine patterns and correlates of HIVST distribution within Chinese MSM's sexual networks., Methods: Data used for this analysis was a part of the process evaluation of an HIVST intervention trial among MSM in Nanjing, China. Between May and October 2017, we enrolled 400 men into the trial. Participants assigned to the intervention group (N = 200) were given three HIVST kits at baseline and could request more during the follow-up periods. We incorporated measures for process evaluation in the self-administered online follow-up surveys. This analysis reported findings from the three-month follow-up survey in the intervention group. Frequencies and percentages were used to describe characteristics of participants who distributed kits to their sexual partners as well as patterns of distribution. Multivariable logistic regression was conducted to identify independent correlates of participants who distributed the kits., Results: Of the 177 participants retained (88.5%) at the three-month follow-up, 72 (40.7%) distributed one or more kits to either primary or casual partners. About half of distributors (51.4%) gave one HIVST kit to their sexual partners while 15.3% distributed 3 or more. Over half gave these kits (58.3%) to primary sexual partners while 27.8% reported giving the kits to both primary and casual partners. About half (54.2%) of distributors used the kits together with their partners. Compared to participants who had an HIV test in the past six months, those who tested over six months ago or never tested had significantly lower odds of distributing the kits (AOR = 0.484, 95% CI: 0.250-0.983, p = 0.032). Compared to those who had not used the kits themselves, participants who did had significantly higher odds of distributing the kits (AOR = 3.345, 95% CI: 1.488-7.517, p = 0.003). Participants who reported higher HIV testing efficacy had 2.051 fold greater odds (95% CI: 1.062-3.961, p = 0.033) of distributing the kits compared to those who had lower efficacy., Conclusion: Our study demonstrated that a sexual network-based approach to distributing HIVST among Chinese MSM is feasible and can be a promising strategy to improve the effectiveness of HIVST programs including its reach to untested men. Such approach should be complimented by intervention components that enhance HIV testing efficacy and improve experiences of HIVST., Competing Interests: The authors have declared that no competing interests exist.

Background: Heterosexual transmission has contributed greatly to the current HIV-1 epidemic in China. However, the HIV-1 genetic characteristics in the heterosexually transmitted population in Jiangsu province remained unclear., Methods: A molecular epidemiological investigation on heterosexual transmission of HIV-1 was conducted across Jiangsu province. 301 HIV-1 patients infected through heterosexual transmission were involved in this study. The epidemiological information was investigated by trained staff via face-to-face interviews. Blood samples were taken from each patient, HIV-1 RNA was extracted from the plasma, and used for amplifying the gag and env genes followed by further products sequencing. The genotypes of HIV-1 were determined using phylogenetic tree analyses in the neighbor-joining method., Results: A total of 262 samples were successfully taken for genotyping. The main subtypes which accounted for 90.5% of all HIV-1 strains are CRF01_AE (45.4%), CRF07_BC (21.4%), subtype B (12.6%), CRF08_BC (11.1%). Minor subtypes were also detected, such as CRF68_01B, subtype C, CRF55_01B, CRF02_AG and subtype A. Time trend analysis suggested the prevalence of subtype B and CRF08_BC decreased gradually, but the prevalence of CRF01_AE increased over time. A relatively higher prevalence of CRF07_BC in Central Jiangsu and subtype B were detected in South Jiangsu, while a relatively lower prevalence of subtype B and CRF08_BC were detected in Central Jiangsu., Conclusion: Complex and unbalanced HIV distribution characteristics suggest that heterosexual transmission of HIV needs to be taken seriously. It is necessary to implement more effective and comprehensive intervention strategies for further control of HIV-1 dissemination.

Men who have sex with men (MSM) in China face high rates of HIV and syphilis infection exacerbated by internal migration. Studies on the differences of HIV and syphilis epidemics changing trends in high-risk behaviors and geographic distribution between resident and migrant MSM in Jiangsu, China were conducted. MSM were recruited from 14 surveillance sites in the serial cross-sectional study. Data on demographics, sexual behaviors, HIV and syphilis prevalence were collected. Participants were classified as residents or migrants based on household registration. During 2010-2014, 19,750 MSM were investigated. Engaged in anal sex (76.3% to 80.2%, P < 0.01) as well as received HIV-related services (72.1% to 79.2%, P < 0.01) were increasing. In contrast, engaged in commercial anal sex with males (7.4% to 5.0%, P < 0.01) and drug use (1.6% to 0.8%, P < 0.01) were decreasing. HIV prevalence ranged between 8.6% to 9.6%, while syphilis prevalence decreased over time (13.4-6.8%, P < 0.01). Further, we found that migrant MSM were more likely to engage in condomless anal sex, also had a higher HIV and syphilis prevalence than resident. During the study period, while syphilis prevalence decreased, higher rates of risk behaviors among migrant MSM called for targeted intervention strategies to reduce the HIV transmission.

Background : Heterosexual transmission (HST) has become the current predominant transmission pathways of the HIV-1 epidemic in China. The aim of this study was to explore the geographic and dynamic change of HIV-1 subtypes through HST in China from published studies. Methods : Several electronic databases were searched to identify the studies, and the overall prevalence of HIV-1 subtypes was estimated by a meta-analysis method. Subgroup analysis was conducted by study region and time period. Publication bias was evaluated using Egger's test. The χ ² test was used to evaluate the proportion differences among subgroups. Sensitivity analysis was carried out to assess the stability of the overall prevalence estimates. Results: 42 studies were included in our final analysis. The overall prevalence of CRF01&#95;AE was 46.34% (95% CI: 40.56-52.17%), CRF07&#95;BC was 19.16% (95% CI: 15.02-23.66%), B/B' was 13.25% (95% CI: 9.68-17.25%), CRF08&#95;BC was 10.61% (95% CI: 7.08-14.70%), and C was 4.29% (95% CI: 1.85-7.48%). In subgroup analysis, the prevalence of CRF01&#95;AE and CRF07&#95;BC increased, while the prevalence of B/B' decreased over time, whereby the prevalence of CRF07&#95;BC and CRF08&#95;BC have exceeded that of B/B' since 2010. A significant higher prevalence of CRF01&#95;AE was found in the South provinces, CRF07&#95;BC in East provinces, CRF08&#95;BC and C in Southwest provinces, and B/B' in North provinces. Conclusions : The HIV-1 prevalent strains have evolved into complicated and diverse subtypes, and the proportion of HIV-1 subtypes through HST has changed constantly in different regions and periods in China. This highlights the urgent need to vigorously strengthen the prevention and control of the HIV-1 epidemic., Competing Interests: The authors declare no conflict of interest.

The National Free Antiretroviral Treatment Program was implemented in Jiangsu Province, China in 2005. We conducted a retrospective, open cohort study to determine treatment failure rates and associated risk factors. Data were obtained from the national web-based antiretroviral treatment database. WHO criteria were used to define immunologic treatment failure. Kaplan-Meier methods were used to determine treatment failure rates and Cox proportional hazards modeling was used to identify risk factors. A total of 5,083 (87.8%) having at least one CD4 cell count measure were included from 2005 to 2013. Overall, 30.4% had immunologic treatment failure with cumulative treatment failure rates increasing to 50.5% at month 60 and 64.1% at month 90. Factors predicting treatment failure included being treated in the Centers for Disease Control and Prevention system (HR 1.69, 95% CI 1.14-2.50, p = 0.009) or jail hospital (HR 1.20, 95% CI 1.08-1.34, p = 0.001), and having a baseline CD4 count >350 cells/uL (HR 2.37, 95% CI 1.94-2.89. p < 0.001). Immunologic treatment failure was moderate to substantial among treated HIV patients. Providing second-line regimens and shifting treatment providers to professional hospitals should be considered to consolidate gains in averting morbidity and mortality.

Background: HIV testing is the first point of HIV treatment entry for HIV-infected individuals and an avenue to engage persons at risk in prevention. In China, where the prevalence of HIV among men who have sex with men (MSM) has been rising over the last decade, uptake of HIV testing has been low., Methods: We examined changes in HIV testing in the preceding 12 months through two cross-sectional surveys conducted among MSM in Nanjing, Jiangsu province, China in 2008 and 2012. Respondent-driven sampling (RDS) was used to recruit participants. Questionnaire interviews and venous blood were collected to measure HIV testing, risk behaviors, and prevalence of HIV, syphilis, and HSV-2., Results: A total of 430 and 589 MSM were surveyed in 2008 and 2012, respectively, with comparable samples in each round with respect to demographic characteristics. HIV testing in the past 12 months increased significantly from 20.1% (95% CI 13.3-26.8) in 2008 to 46.0% (95% CI 39.3-51.4, p < 0.001) in 2012. HIV prevalence was stable, at 6.6% (95% CI 2.5-11.3) in 2008 and 10.1% (95% CI 6.6-13.9, p = 0.240) in 2012, as was syphilis (14.3% in 2008 vs. 9.9% in 2012, p = 0.240). HSV-2 prevalence (18.6% in 2008 vs. 10.2% in 2012, p = 0.040) and self-reported STI in the last year (24.3% in 2008 vs. 14.3% in 2012, p = 0.020) significantly decreased. Changes in reported sexual behaviors were mixed and the profiles of who did and did not test varied between 2008 and 2012., Conclusions: HIV testing uptake more than doubled among MSM in Nanjing from 2008 to 2012 -a period of massive promotion and scale up of testing programs for MSM. However, additional efforts are still needed to further increase the proportion of men being not only tested but also undergoing repeat testing if they engage in continued risk taking behavior.

Many men who have sex with men (MSM) do not use condoms with their main partners, especially if both parties are of the same HIV status. However, significant proportions of MSM have never tested or recently tested and are unaware of their main partners' HIV status. A cross-sectional survey was conducted among 524 MSM in Jiangsu, China in 2013-2014. Time-location sampling and online convenience sampling were used to recruit participants. We compared awareness of HIV status and recent HIV testing between participants who had main partners versus those who did not, and identified factors associated with recent HIV testing among men in main partnerships. Participants in main partnerships were significantly more likely to report recent HIV testing and being HIV-negative instead of HIV-unknown compared to participants in casual partnerships only. Overall, 74.5 % of participants were aware of their main partners' HIV status. Among participants in main partnerships, those who had 2-5 male anal sex partners in the past 6 months and those who reported that their partners were HIV-negative had 2.36 (95 % CI 1.12, 4.97) and 4.20 (95 % CI 2.03, 8.70) fold greater odds of being tested in the past year compared to those who had main partners only and those whose partners were HIV-positive/unknown, respectively. Chinese MSM in main partnerships might be practicing serosorting and may be at lower risk for HIV infection due to increased awareness of main partners' HIV status and higher uptake of recent testing.

Increasing prevalence of sexually transmitted diseases (STD) was reported among men who have sex with men (MSM) in China. A total of 407 MSMs were recruited by respondent-driven sampling (RDS) from May to July 2008 in Nanjing, China. Face-to-face interviews were conducted to collect information on demographic and risk behaviors; blood samples were collected for HIV and syphilis antibodies testing. The adjusted HIV and syphilis prevalence were, respectively, 7.3% (confidence interval [CI] = 2.6%-10.2%) and 14.4% (95% CI = 9.3%-21.1%). Recruiting male sex partners mostly from saunas and receptive anal intercourse with men in the last 6 months were independently associated with positive HIV status. Risk factors for positive syphilis status included being older than 28 years, low level of HIV-related knowledge, having been a male sex worker, and having unprotected anal sex with casual male sex partners in the past 6 months. High HIV/STD prevalence was detected. HIV/STD prevention strategies are urgently warranted., (© 2013 APJPH.)

Substantial numbers of Chinese men who have sex with men (MSM) do not access facility-based HIV testing. Self-testing could promote testing uptake among this population. We describe experiences and identify correlates of self-testing among Chinese MSM. A cross-sectional survey was conducted among MSM in Jiangsu from November 2013 to January 2014. Participants were recruited through time-location sampling and from online. Participants were asked a series of questions about HIV self-testing uptake and associated experiences. Logistic regression was used to identify correlates of having ever self-tested for HIV. Of 522 participants, 26.2 % had ever self-tested. Finger stick was the most common self-testing modality (86.1 %). A majority of participants reported that it was "very easy" (43.1 %) or "somewhat easy" (34.3 %) to perform self-testing while lower proportions reported "very confident" (24.1 %) or "somewhat confident" (36.5 %) in the accuracy of their test results. Having ever self-tested was significantly associated with having had 2-5 and 6 or more male anal sex partners in the past 6 months (AOR 2.12, 95 % CI 1.00, 4.49; AOR 4.95, 95 % CI 1.90, 12.87), having ever tested for HIV (AOR 4.56, 95 % CI 1.66, 12.55), and having a friend or friends who self-tested (AOR 7.32, 95 % CI 3.57, 15.00). HIV self-testing can reach untested Chinese MSM and/or increase testing frequency. Peer- or social network-based interventions could futher help encourage self-testing. Monitoring systems should be strengthened to ensure the quality of self-testing kits and provision of essential support services, including post-test counseling and linkage-to-care.

Background: Prevalence of The transmitted HIV drug resistance (THDR) has been reported in many countries. In China, the low level THDR was found in only a few provinces. To know the transmitted HIV drug resistance in east of China, we investigated THDR during 2009-2011 in Jiangsu province of China., Methods: Between January and August of 2009, 2010, and 2011, we consecutively collected 50, 54, 53 blood specimens respectively from qualified individuals at surveillance sentinel sites in Jiangsu province according to protocol of HIV Drug Resistance Threshold Survey (HIVDR-TS) recommended by WHO. The region of pol gene including protease and partial retro-transcriptase was amplified, sequenced and edited. Then the sequences were submitted to HIV drug resistance database to analysis transmitted HIV drug resistance mutations using Calibrated Population Resistance tool. The reference sequences of different HIV-1 subtypes were downloaded from HIV database and Genebank. The phylogenetic trees were inferred using the neighbor-joining method., Results: Our results show that THDR has been at low level from 2009 to 2011, only K101E and V179D mutation was detected which did not belong to the major HIV-1 drug resistance mutations. Phylogenetic analysis showed that CRF01&#95;AE is the predominant subtype, and followed by CRF07&#95;BC and B subtype. Subtype B consists of the two distinct clusters., Conclusions: The low level of THDR suggests that anti-retroviral treatment was implemented more effectively and THDR surveillance should be conducted two years later in Jiangsu province of China. CRF01&#95;AE has become the predominant subtype and dual infection of HIV may be common in Jiangsu province.

Objective: To analyze the five-year effectiveness of the people living with HIV/AIDS who initially received highly active antiretroviral therapy (HAART) in Jiangsu province., Methods: HIV/AIDS initially received HAART from 1 Jan 2005 to 31 May 2014 in Jiangsu province with the CD4(+)T cell count tested in baseline, 6 months, 1 year, 2 years, 3 years, 4 years and 5 years after treatment initiation were selected. According to their retrospectively collected baseline and follow-up data, statistical analysis was performed using SPSS 16.0 software to analyze the variation of CD4(+)T counts and its impact factors in different times after treatment initiation., Results: A total of 200 patients were included. A total of 134 patients were men, and 66 were women, the ratio of male to female was 2.03: 1; mean age was (39.7 ± 10.3) years old; 69.0% (138/200) of the patients married; 53.0% (106/200) as the most were infected with HIV through heterosexual transmission, and followed by men who have sex with men (MSM) (25.5%, 51/200); taken together as 78.5% (157/200).58.5% (117/200) were treated in the CDC. The mean (95%CI) baseline CD4(+)T cell count of cases was 106.9 (93.3-120.5) cells/µl; the CD4(+)T count tested in 6 months, 1 year, 2 years, 3 years, 4 years and 5 years after treatment initiation were 107.3, 152.9, 221.6, 260.0, 281.3 and 316.4 cells/µl more than baseline respectively; the CD4(+)T count after treatment initiation has increased over time (F = 201.06, P < 0.01) . The mean(95%CI) CD4(+)T count tested in 5 years after treatment initiation can increase to 540.7(445.4-635.9) cells/µl with a baseline CD4(+)T count more than 200 cells/µl, but in the subgroups with a baseline CD4(+)T count less than or equal to 50 cells/µl, 51-100 cells/µl, 101-150 cells/µl and 151-200 cells/µl, it only can reach to 431.4 (375.9-487.0), 400.0 (339.9-460.2), 380.3 (330.6-430.0) and 412.1 (369.3-454.8) cells/µl respectively. The mean (95%CI) CD4(+)T count tested in 5 years after treatment initiation with 1 baseline symptom categories can increase to 449.2 (392.2-506.2) cells/µl, while 409.1(317.8-500.5)cells/µl in the subgroup with baseline symptom categories more than or equal to 2. The CD4(+)T after treatment increased slowly associated with a lower baseline CD4(+)T count level and more baseline symptom categories (F values were 3.96 and 2.35, P < 0.01)., Conclusion: It has a remarkable effectiveness for HIV/AIDS treatment in Jiangsu province. The patients with a baseline CD4(+)T count more than 200 counts/µl have a better immune function recovery.

Objectives: To examine outcomes of a peer-led, community-based intervention providing rapid HIV testing and case management for linkage to care for untested men who have sex with men (MSM) in China., Methods: Rapid HIV testing was performed by trained peer volunteers of a community-based organisation (CBO) in three cities of Jiangsu province at MSM-oriented venues. MSM screened positive were referred and accompanied to local government health agencies (Centres for Disease Control and Prevention (CDC)) for confirmatory HIV testing and provided social support for up to 1 month. Data for the programme were compared with sentinel surveillance surveys of MSM conducted by the national and provincial CDC in the province during the same year to assess differences in the populations reached, in HIV positivity, and linkage to HIV care., Results: A total of 512 previously untested MSM were tested by the CBO programme in 6 months. Compared with those in the surveillance surveys, MSM tested by the CBO were significantly more likely to be younger, single, non-resident of the province, more educated and used condoms less frequently. Higher proportions of HIV-positive MSM screened by the CBO received their confirmatory test results (98.1% vs 72.6%, p<0.001) and linked to care (90.4% vs 42.0%, p<0.001)., Conclusions: Trained peers providing rapid HIV testing with social support and case management through the early period following diagnosis can efficiently expand HIV testing and improve linkage to care among MSM in China., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.)

Background: A large number of men who have sex with men (MSM) and people living with HIV/AIDS (PLHA) are underserved despite increased service availability from government facilities while many community based organizations (CBOs) are not involved. We aimed to assess the feasibility and effectiveness of the task shifting from government facilities to CBOs in China., Methods: HIV preventive intervention for MSM and follow-up care for PLHA were shifted from government facilities to CBOs. Based on 'cash on service delivery' model, 10 USD per MSM tested for HIV with results notified, 82 USD per newly HIV cases diagnosed, and 50 USD per PLHA received a defined package of follow-up care services, were paid to the CBOs. Cash payments were made biannually based on the verified results in the national web-based HIV/AIDS information system., Findings: After task shifting, CBOs gradually assumed preventive intervention for MSM and follow-up care for PLHA from 2008 to 2012. HIV testing coverage among MSM increased from 4.1% in 2008 to 22.7% in 2012. The baseline median CD4 counts of newly diagnosed HIV positive MSM increased from 309 to 397 cells/µL. HIV tests among MSM by CBOs accounted for less than 1% of the total HIV tests in Nanjing but the share of HIV cases detected by CBOs was 12.4% in 2008 and 43.6% in 2012. Unit cost per HIV case detected by CBOs was 47 times lower than that by government facilities. The coverage of CD4 tests and antiretroviral therapy increased from 71.1% and 78.6% in 2008 to 86.0% and 90.1% in 2012, respectively., Conclusion: It is feasible to shift essential HIV services from government facilities to CBOs, and to verify independently service results to adopt 'cash on service delivery' model. Services provided by CBOs are cost-effective, as compared with that by government facilities.

CRF01&#95;AE and subtype B are the two of major HIV-1 clades circulating in China. HIV spread more rapidly among men who have sex with men (MSM) than among populations with other risk behaviors. In Jiangsu province in China, the HIV-1 incidence among MSM was more than 3.8%. Our previous study showed that almost equal proportions of CRF01&#95;AE, B, and CRF07&#95;BC were circulating among MSM. Moreover, many kinds of CRF01Bs have been identified among MSM in Southeast Asia in recent years. It is therefore inevitable that recombination between CRF01&#95;AE and subtype B will emerge among MSM in Jiangsu province in China. Here we identify a novel recombinant of CRF01&#95;AE/B that has a distinctly different genome structure from other CRF01Bs and unique recombinant forms (URFs) previously identified. An analysis of the near full-length sequence of JS2010001 showed that it is composed of at least three interlaced CRF01&#95;AE and B segments. Recently, many kinds of URFs and C circulating recombinant forms (CRFs) have emerged among MSM in China within a short period of time, which suggests that dual infection of HIV-1 among MSM in China is very common and that more effective intervening measures to prevent the spread of HIV among MSM should be taken.

The HIV epidemic among men who have sex with men (MSM) in China is severe. Peer can induce risky and preventive behaviors among MSM. We interviewed 220 MSM who had at least one significant other who was a peer MSM (SOPM). Interviews were conducted at two gay venues in Suzhou, China, which reported five HIV-related outcomes: HIV (8.2 %), syphilis (16.4 %), self-reported sexually transmitted infection symptoms (14.6 %), unprotected anal intercourse (UAI; 58.6 %) and having had taken up HIV testing (40.4 %). Adjusting for significant background variables, participants' perceived characteristics of the social network of SOPM, such as practicing risk behavior (e.g. UAI) or preventive behaviors (e.g. HIV antibody testing), or possessing HIV-related perceptions (e.g. dislike in condom use), were significantly associated with some of the five aforementioned outcomes (p < 0.05). Peer education and peer-based interventions involving significant others are hence potentially important in HIV prevention targeting MSM. Future pilot intervention studies are warranted.

Few data exist on HIV disease progression and antiretroviral treatment (ART) impact among men who have sex with men (MSM) in China. Using data from the national case reporting system from 2004 to 2010, we describe changes in CD4 cell count before and after ART initiation, disease progression, and mortality among MSM in Jiangsu province compared with other persons living with HIV/AIDS. Median CD4 cell count among MSM at HIV diagnosis was 432 and decreased rapidly in 12 months to below the level of heterosexuals (slope: MSM -38.0, heterosexuals -15.5, injection drug users [IDU] -8.0, blood donors -10.5). Among those initiating ART, median CD4 cell count among MSM was 157, yet the increase in count was slower than for other groups (slope: MSM 26.9, heterosexuals 31.9, IDU 29.0, blood donors 35.0). Progression to AIDS was faster among MSM than heterosexuals and IDU. For the present, the mortality rate was lower for MSM compared with heterosexuals and blood donors; however, against a backdrop of more recent infection (ie, MSM had younger age, and 93.8 % were diagnosed after 2008), findings suggest a survival rate for MSM that will fall behind other groups. Improved medical and psychosocial supportive care is needed for this stigmatized population lest disparities become greater.

Barriers to HIV testing and HIV care and treatment pose significant challenges to HIV prevention among men who have sex with men (MSM) in China. We carried out a qualitative study to identify barriers and facilitators to HIV testing and treatment among Chinese MSM. In 2012, seven focus group (FG) discussions were conducted with 49 MSM participants in Nanjing, China. Purposive sampling was used to recruit a diverse group of MSM participants. Semi-structured interviews were conducted to collect FG data. Major barriers to testing included gay- and HIV-related stigma and discrimination, relationship type and partner characteristics, low perception of risk or threat, HIV is incurable or equals death, concerns of confidentiality, unaware that testing is offered for free, and name-based testing. Key facilitators of testing included engaging in high-risk sex, sense of responsibility for partner, collectivism, testing as a part of standard/routine medical care, MSM-friendly medical personnel, increased acceptance of gay/bisexual men by the general public, legal recognition and protection of homosexuals, and home self-testing. Barriers to treatment included negative coping, nondisclosure to families, misconceptions of domestically produced antiretroviral drugs (ARVs) and the benefits of treatment, and costs associated with long-term treatment. Facilitators of treatment included sense of hopefulness that a cure would be found, the cultural value of longevity, peer social support and professional psychological counseling, affordable and specialized treatment and care, and reduced HIV-related stigma and discrimination. Finally, for both testing and treatment, more educational and promotional activities within MSM communities and among the general public are needed.

Rectal pre-exposure prophylaxis (PrEP) will be a critical component of HIV prevention products due to the prevalence of unprotected receptive anal intercourse among men who have sex with men and heterosexual couples. Given the biological considerations of this compartment and the complexity of HIV infection, design of a successful rectal microbicide product faces a number of challenges. Important information is being compiled to begin to address deficits in knowledge toward design of rectal PrEP products for men and women. Aspects of formulation development and preclinical and clinical evaluation of rectal products studied to date are summarized in this review. This article is based on a presentation at the "Product Development Workshop 2013: HIV and Multipurpose Prevention Technologies," held in Arlington, Virginia on February 21-22, 2013. It forms part of a special supplement to Antiviral Research., (Copyright © 2013 Elsevier B.V. All rights reserved.)

Background: Respondent-driven-sampling (RDS) has well been recognized as a method for sampling from most hard-to-reach populations like commercial sex workers, drug users and men who have sex with men. However the feasibility of this sampling strategy in terms of recruiting a diverse spectrum of these hidden populations has not been understood well yet in developing countries., Methods: In a cross sectional study in Nanjing city of Jiangsu province of China, 430 MSM were recruited including 9 seeds in 14 weeks of study period using RDS. Information regarding socio-demographic characteristics and sexual risk behavior were collected and testing was done for HIV and syphilis. Duration, completion, participant characteristics and the equilibrium of key factors were used for assessing feasibility of RDS. Homophily of key variables, socio-demographic distribution and social network size were used as the indicators of diversity., Results: In the study sample, adjusted HIV and syphilis prevalence were 6.6% and 14.6% respectively. Majority (96.3%) of the participants were recruited by members of their own social network. Although there was a tendency for recruitment within the same self-identified group (homosexuals recruited 60.0% homosexuals), considerable cross-group recruitment (bisexuals recruited 52.3% homosexuals) was also seen. Homophily of the self-identified sexual orientations was 0.111 for homosexuals. Upon completion of the recruitment process, participant characteristics and the equilibrium of key factors indicated that RDS was feasible for sampling MSM in Nanjing. Participants recruited by RDS were found to be diverse after assessing the homophily of key variables in successive waves of recruitment, the proportion of characteristics after reaching equilibrium and the social network size. The observed design effects were nearly the same or even better than the theoretical design effect of 2., Conclusion: RDS was found to be an efficient and feasible sampling method for recruiting a diverse sample of MSM in a reasonable time.

HIV and AIDS incidence in China is high among men who have sex with men (MSM) and ours was one of few studies in China to evaluate the role of HIV risk reduction counseling and testing. Respondent-driven sampling (RDS) was used to recruit 430 MSM. Participants were followed up at 6, 12 and 18 months to evaluate behavioral changes after counseling to reduce risk behaviors. At baseline, HIV prevalence was 4.7%, whereas HIV incidence was 5.2 per 100 person-years. The incidence was 3.8 during six to 12 months, and 1.1 during 12 to 18 months. During the study period, the reported unprotected anal intercourse (UAI) significantly decreased from 60.9% to 42.9%. The proportion of participants who had one or no partner significantly increased from 40.9% to 48.0%. The study also found that some risk behaviors decreased between baseline and 12 months, followed by a slight increase between 12 and 18 months. Reductions in UAI can be achieved through counseling and testing, but may wane over time. Future programs should consider HIV risk-reduction counseling and testing for interventions in MSM in China.

Unprotected anal intercourse (UAI) is a well-documented risk factor for acquiring HIV, but not well-studied in China. We studied demographic and behavioral correlates for UAI among men who have sex with men (MSM) in a respondent-driven-sampling (RDS) survey in Nanjing, China. Four hundred and thirty MSM (including ten seeds) participated in this study, rendering an adjusted rate of UAI as 62.3 % (95 % CI 56.4-68.4 %). Adjusted HIV and syphilis prevalence rates were 6.6 % (95 % CI 3.0-10.4) and 12.6 % (95 % CI 8.1-18.3), respectively. HIV- and syphilis-positive cases were more likely to have engaged in UAI. Being unwilling to use condoms, meeting partners in non-conventional venues, having multiple male sex-partners in the past 6 months, having sex with regular and casual male partners in the past 6 months, and consumption of alcohol before sex were all positively associated with UAI. Based on the observed high prevalence of UAI among MSM in Nanjing, we can conclude that implementation of strategies to motivate MSM with high-risk behaviors to use condoms is urgently required in Nanjing.

Background: HIV prevalence is high among men who have sex with men (MSM) in China. Longitudinal studies are needed to measure HIV incidence, determine causes of acquisition, and test prevention interventions. We described 2 novel methods to enroll and maintain a cohort of MSM, focusing on their abilities to establish a diverse sample, improve retention, and their impact on HIV incidence., Methods: Employing methods based on respondent-driving sampling, we constructed 2 parallel cohorts measuring HIV incidence over 2 years through 6-month follow-up visits. An initial cohort was constructed using long-chain peer referral from the community; a second phase comprised open cohort peer referral recruitment from MSM completing follow-up., Results: Three-hundred ninety-seven HIV-negative MSM were enrolled in the initial cohort; 460 were recruited in the open cohort phase. Across recruitment waves, the composition of the cohort was stable. Among initial participants, retention was 72.0%, 68.8%, 49.9%, and 44.8%. Retention was lower in the open cohort. MSM retained in both phases were less risky than those lost to follow-up. HIV incidence was 3.36 per 100 person-years and did not differ by recruitment method., Conclusions: Our approach efficiently recruited MSM into longitudinal studies with modest improvement in sample diversity from initial recruits. We perceive multiple means to improve diversity and follow-up capitalizing on the network bonds between recruits and through secondary incentives for assistance with referral and retention. Meanwhile, HIV incidence is high among MSM in Nanjing, and interventions need to be developed and tested in longitudinal randomized controlled trials.

Background: The study was to investigate the incidence of HIV-1 and related factors, as well as predictors associated with retention in a cohort study among men who have sex with men (MSM) in Yangzhou, Jiangsu Province, China. A carefully designed 12-month prospective cohort study was conducted., Methodology/principal Findings: A total of 278 sero-negative MSM were recruited and followed up for 12 months starting from May, 2008. Participants were tested for HIV-1 at baseline, 6-month, and 12-month follow-up visits. Questionnaire interviews were conducted to collect information. The retention rate and HIV incidence were analyzed as functions of demographic and behavioral variables. Risk factors were identified by estimating the relative risks (RR) and respective 95% confidence intervals (CI) using a Poisson regression model, univariate and multivariate analyses and risk factors analyses. 71 (25.5%) and 45 (16.2%) of the 278 participants were retained at the 6-month and 12-month follow-up visits respectively. The incidence rates of HIV-1 were 5.65 and 6.67 per 100 person years (PY) respectively. Both having received condoms and having received lubricant were negatively associated with HIV sero-conversion at the 12 months' follow-up. Predictors associated with 12-month retention rate include Yangzhou residency (RR=0.471, 95%CI: 0.275~0.807, P=0.006), having received condoms (RR=0.065, 95%CI: 0.007~0.572, P=0.014), and having received VCTs (RR=0.093, 95%CI: 0.010~0.818, P=0.032)., Conclusions/significance: The incidence of HIV-1 among MSM in Yangzhou is relatively high and effective interventions are needed urgently. More attention should be focused on maintaining a higher retention rate.

Conclusive evidence-based research has shown that circumcision reduces the risk of HIV transmission via heterosexual intercourse, whilst ongoing studies are investigating similar effects via homosexual transmissions and the results are equivocal. Few acceptability studies regarding circumcision were conducted among men who have sex with men (MSM). In this cross-sectional study, a total of 307 MSM were recruited by snowball sampling and were interviewed anonymously by some peer field workers in Yangzhou, China. Amongst all uncircumcised participants (93.4% of all participants were uncircumcised), the willingness to be circumcised increased from 8.1% to 30.7%, before and after the participants were briefed about a hypothetical potential benefit of a 50% risk reduction of circumcision in preventing HIV transmission among MSM. In the multivariate analysis, perception of overly long foreskin (odds ratio [OR] = 6.04), unprotected sexual intercourse with male regular sex partners in the last six months (OR = 2.04), and seeing no chance for contracting HIV in the next 12 months (OR = 0.54) were significantly associated with conditional willingness for circumcision. Adjusting for these variables, other significant factors were identified by multiple logistic regression analysis, including number of perceived disadvantages for having overly long foreskin (adjusted OR = 2.60), variables that were derived from the Theory of Planned Behaviors (TPB), and having some circumcised MSM peers (adjusted OR = 0.45-4.38). Some risk compensation behaviors however, may be practiced by 15.9% of the MSM who were willing to undergo circumcision. The acceptability would increase slightly with the effect size of circumcision in protecting MSM from HIV transmission via homosexual intercourse. However, it was only around 30%, even if circumcision could result in a large (50%) risk reduction in HIV transmission among MSM. If future studies can establish efficacy of circumcision, relevant promotion programs need to guard against risk compensation, though the magnitude of risk compensation may be moderate.

Objective: This study investigated the incidence of syphilis, HIV and hepatitis C virus (HCV), as well as factors associated with syphilis seroconversion among men who have sex with men (MSM) in Nanjing, China., Methods: A cohort of MSM was recruited by respondent-driven sampling methods. Those who were syphilis-, HIV- and HCV-seronegative at the baseline were invited to be retested at month 6. A Poisson regression analysis was performed., Results: Of the 416 participants in the study, 348 participants were HIV-, syphilis- and HCV-negative at the baseline, 250 (71.84%) of whom returned for retesting at month 6. Nine of these 250 participants had seroconverted to syphilis-positive (incidence=7.58 per 100 person-years (PY); 95% CI 2.63 to 12.53 per 100 PY), and five had seroconverted to HIV-positive (incidence=4.17 per 100 PY; 95% CI=0.52 to 7.83 per 100 PY). No HIV and syphilis coinfection and no HCV seroconversion were found. Multivariate analysis identified four statistically significant factors predicting syphilis seroconversion, including currently single marital status (RR=0.32, 95% CI 0.16 to 0.65, p<0.01), monthly income >US$300 (RR=2.68, 95% CI 1.28 to 5.61, p<0.01), self-reported homosexual orientation (RR=0.48, 95% CI 0.24 to 0.96, p<0.05) and recruitment of male sex partners mostly from gay saunas (RR=6.72, 95% CI 2.88 to 15.68, p<0.01)., Conclusions: The high incidence of syphilis and HIV reflects the seriousness and urgency of the HIV and sexually transmitted diseases (STD) epidemics among MSM in China. Effective interventions of syphilis treatment and prevention should target MSM with characteristics reflecting the aforementioned risk factors.

Our recent study showed that almost equal proportions of B, CRFs&#95;BC, and CRF01&#95;AE were circulating among MSM in Jiangsu, suggesting that there is a very high likelihood of generating new intersubtypes/CRFs recombinants. Here, we report an epidemiologically linked cohort including 22 HIV-1-positive IDUs in Jiangsu. Fifteen blood samples were collected to investigate HIV-1 subtype characterization. The analyses of gag-RT regions showed that 14 of these samples belonged to CRF07&#95;BC. Importantly, we detected, for the first time, a novel second-generation HIV-1 recombinant (07JSNJ001) between CRF01&#95;AE and CRF07&#95;BC. The analyses of the near full-length genomic sequence of 07JSNJ001 (GenBank accession number FJ238521) showed that 07JSNJ001 is composed of at least 10 interlaced CRF07&#95;BC and CRF01&#95;AE segments, quite distinct from any previously identified CRF and URF around the world. The detection of the CRF01&#95;AE/CRF07&#95;BC recombinant may be a harbinger of more new intersubtypes/CRFs recombinants occurring in Jiangsu Province.

Objectives: To investigate the prevalence of HIV, hepatitis B (HBV), hepatitis C (HCV), and syphilis among men who have sex with men (MSM) in 2 cities of Jiangsu, China, and to characterize the HIV-1 subtypes prevalent among this population., Methods: During September 2006 and July 2007, 296 and 173 MSM were recruited from Nanjing and Yangzhou, respectively. Sera samples were collected and tested for HIV, HBV, HCV, and syphilis infections. The nucleotide sequences of p17 and C2V3 regions were determined by RT-nested-PCR and sequencing. HIV-1 subtypes were characterized by phylogenetic analysis., Results: The prevalence of HIV, HBV, HCV, and syphilis infections among MSM was 5.8%, 11.1%, 0.7%, and 27.7%, respectively. The prevalence of HIV and syphilis was significantly higher in 2006-2007 than in 2003 (P 0.05). The phylogenetic tree of p17 showed that HIV-1 subtypes B, CRF01&#95;AE, and CRF07&#95;BC accounted for 35.7%, 35.7%, and 28.6%, respectively. The result of C2V3 showed that 45.5%, 36.4%, and 18.2% sequences belonged to HIV-1 subtype B, CRF01&#95;AE, and BC recombinants, respectively. The subtype characterization in Jiangsu was significantly different from those in Beijing (P <0.05). Furthermore, Jiangsu HIV-1 B strains were different from majority of China B' strains and originated from Beijing., Conclusions: The rapidly increasing prevalence and complex subtypes of HIV-1 suggest that effective prevention and intervention strategies are urgently needed for MSM in Jiangsu.

Objective: : The objective of this study was to investigate the prevalence of sexually transmitted diseases (STDs), including HIV infection, and sexual risk behaviors among men who have sex with men (MSM) in Jiangsu Province, China., Design: : The authors conducted a cross-sectional study., Methods: : From February to July 2003, men who attended 10 participating gay bars in five cities in Jiangsu Province were asked to complete a self-administered questionnaire, including measures of alcohol use and sexual risk behaviors. Blood samples and urethral swabs were taken to examine the presence of STDs, including HIV infection., Results: : A total of 144 men were recruited in the study. Forty-six percent of men reported unprotected anal intercourse with their male sexual partners in the past 3 months. No one was found to be HIV-infected, but the prevalence of STDs was high: gonorrhea 2.7%, chlamydial infection 8.0%, nonchlamydial nongonococcal urethritis 27.7%, active syphilis 6.9%, hepatitis B virus infection 9.1%, herpes simplex virus-2 infection 7.8%, and genital warts 13.2%., Conclusions: : Given that HIV prevalence among MSM in some other parts of China has been as high as 3%, STDs facilitate the transmission of HIV, and high prevalence of STDs and sexual risk behaviors among MSM exist in Jiangsu Province, the potential for the future spread of HIV is of concern, and it is urgent to provide MSMs with STD healthcare services and HIV/AIDS/STD prevention education and intervention.

The prevalence of HIV among men who sex with men (MSM)has been increasing sharply in China. The prevalence of unprotected anal intercourse (UAI)among them is very high, especially when male regular sex partners are involved. Many MSM having regular sex partners are engaged in multiple sex partnerships, which often involved UAI. This study interviewed 168 MSM in Nanjing, China, having had anal intercourse with at least one male regular sex partner in the last six months. Amongst the participants, 52.4% reported having had UAI with male regular sex partners whilst 50.0% reported multiple male sex partnerships in the last six months. Multivariate analysis showed that monthly personal income higher than 2000 RMB (multivariate OR = 0.49, 95% CI: 0.26–0.96), HIV antibody testing in the last year (multivariate OR = 0.19, 95% CI: 0.06–0.60), sexual position being both insertive and receptive during anal sex with male sex partners in general (multivariate OR = 0.43, 95% CI: 0.18–0.99; reference group: with receptive position only) were associated with lower likelihoods of UAI. Syphilis-related perceptions, including knowledge, cognitions (perceived susceptibility, perceived severity, self-efficacy in avoiding syphilis infection and perceived infectivity and perceived syphilis-related norms among MSM in general)were not associated with risk behaviors (UAI and multiple male sex partnerships). Our sampled MSM are exposed to very high risk of HIV/STD transmission. We found no association between syphilis-related perceptions and the two types of risk behaviors. Future studies are warranted to understand such associations in the context of sexual intercourse with nonregular sex partners among MSM. [ABSTRACT FROM AUTHOR]

The HIV-1 protein Nef inhibits antigen presentation by class I major histocompatibility complex (MHC-I). We determined the mechanism of this activity by solving the crystal structure of a protein complex comprising Nef, the MHC-I cytoplasmic domain (MHC-I CD) and the ?1 subunit of the clathrin adaptor protein complex 1. A ternary, cooperative interaction clamps the MHC-I CD into a narrow binding groove at the Nef-?1 interface, which encompasses the cargo-recognition site of ?1 and the proline-rich strand of Nef. The Nef C terminus induces a previously unobserved conformational change in ?1, whereas the N terminus binds the Nef core to position it optimally for complex formation. Positively charged patches on ?1 recognize acidic clusters in Nef and MHC-I. The structure shows how Nef functions as a clathrin-associated sorting protein to alter the specificity of host membrane trafficking and enable viral evasion of adaptive immunity. [ABSTRACT FROM AUTHOR]