Too many people with HIV have left the job market permanently and those with reduced work capacity have been unable to keep their jobs. There is a need to examine the health effects of labor force participation in people with HIV. This study presents longitudinal data from 1,415 HIV-positive men who have sex with men taking part in the Multicenter AIDS Cohort Study. Generalized Estimating Equations show that employment is associated with better physical and mental health quality of life and suggests that there may be an adaptation process to the experience of unemployment. Post-hoc analyses also suggest that people who are more physically vulnerable may undergo steeper health declines due to job loss than those who are generally healthier. However, this may also be the result of a selection effect whereby poor physical health contributes to unemployment. Policies that promote labor force participation may not only increase employment rates but also improve the health of people living with HIV.
Cryopreservation of peripheral blood mononuclear cells (PBMC) allows assays of cellular function and phenotype to be performed in batches at a later time on PBMC at a central laboratory to minimize assay variability. The Multicenter AIDS Cohort Study (MACS) is an ongoing prospective study of the natural and treated history of human immunodeficiency virus (HIV) infection that stores cryopreserved PBMC from participants two times a year at four study sites. In order to ensure consistent recovery of viable PBMC after cryopreservation, a quality assessment program was implemented and conducted in the MACS over a 6-year period. Every 4 months, recently cryopreserved PBMC from HIV-1-infected and HIV-1-uninfected participants at each MACS site were thawed and evaluated. The median recoveries of viable PBMC for HIV-1-infected and -uninfected participants were 80% and 83%, respectively. Thawed PBMC from both HIV-1-infected and -uninfected participants mounted a strong proliferative response to phytohemagglutinin, with median stimulation indices of 84 and 120, respectively. Expression of the lymphocyte surface markers CD3, CD4, and CD8 by thawed PBMC was virtually identical to what was observed on cells measured in real time using whole blood from the same participants. Furthermore, despite overall excellent performance of the four participating laboratories, problems were identified that intermittently compromised the quality of cryopreserved PBMC, which could be corrected and monitored for improvement over time. Ongoing quality assessment helps laboratories improve protocols and performance on a real-time basis to ensure optimal cryopreservation of PBMC for future studies.
We assessed associations of herpes simplex virus types 1 and 2 (HSV-1 and -2), cytomegalovirus (CMV), and human herpesvirus 8 (HHV-8) infection with subclinical coronary atherosclerosis in 291 HIV-infected men in the Multicenter AIDS Cohort Study. Coronary artery calcium (CAC) was measured by non-contrast coronary CT imaging. Markers for herpesviruses infection were measured in frozen specimens collected 10-12 years prior to case identification. Multivariable logistic regression models and ordinal logistic regression models were performed. HSV-2 seropositivity was associated with coronary atherosclerosis (adjusted odds ratio [AOR] =4.12, 95% confidence interval [CI] =1.58-10.85) after adjustment for age, race/ethnicity, cardiovascular risk factors, and HIV infection related factors. Infection with a greater number of herpesviruses was associated with elevated CAC levels (AOR=1.58, 95% CI=1.06-2.36). Our findings suggest HSV-2 may be a risk factor for subclinical coronary atherosclerosis in HIV-infected men. Infection with multiple herpesviruses may contribute to the increased burden of atherosclerosis.
herpesvirus; HSV-2; atherosclerosis; HIV-1/AIDS; risk factors
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.
It is challenging to collect accurate and complete data on sensitive issues such as sexual behaviors. Our objective was to explore experience and perceptions regarding the use of a locally programmed color-coded audio computer-assisted self interview (C-ACASI) system among men and women in a semi-rural setting in south India. We conducted a mixed-methods cross-sectional survey using semi-structured interviews among 89 truck drivers and 101 truck driver wives who had participated earlier in the C-ACASI survey across a predominantly rural district in Tamil Nadu. To assess the color-coded format used, descriptive quantitative analysis was coupled with thematic content analysis of qualitative data. Only 10 % of participants had ever used a computer before. Nearly 75 % did not report any problem in using C-ACASI. The length of the C-ACASI survey was acceptable to 98 % of participants. Overall, 87 % of wives and 73 % of truck drivers stated that C-ACASI was user-friendly and felt comfortable in responding to the sensitive questions. Nearly all (97 %) participants reported that using C-ACASI encouraged them to respond honestly compared to face-to-face personal interviews. Both the drivers and wives expressed that C-ACASI provided confidentiality, privacy, anonymity, and an easy mechanism for responding truthfully to potentially embarrassing questions about their personal sexual relationships. It is feasible and acceptable to use C-ACASI for collecting sensitive data from poorly computer-literate, non-English-speaking, predominantly rural populations of women and men. Our findings support the implementation of effective and culturally sensitive C-ACASI for data collection, albeit with additional validation.
Color-coded ACASI; Computer interview; Sensitive questions; Acceptability; Rural India
A 2009 survey of 418 venue-based male commercial sex workers (male CSWs) in Shenzhen, China revealed that 19.9% used recreational drugs. Consistent condom use by drug users was lower than by non-users. HIV, syphilis, and herpes simplex virus 2 (HSV-2) prevalence, however, were higher among drug users. Prevention programs need to address drug use among male CSWs in China.
Objective: To document knowledge, attitudes and practices of voluntary HIV counselling and testing (VCT) among rural migrants in central China. Methods: A cross-sectional study with face-to-face anonymous questionnaire interviews was conducted using a structured questionnaire. Results: Among 1280 participants, 87.9% reported having had sexual intercourse during their lifetime, with 69% of singles reporting having had sexual intercourse and 49.1% having had sex in the past month. Only 21% always used condoms, 84.4% knew HIV infection was diagnosed through blood testing, 56.6% had heard of VCT, but only 3.8% perceived their own risk for HIV infection. Only 43 (2.3%) had ever been tested for HIV, and none had ever been tested at a VCT site. About two-thirds (64.5%) would be willing to use VCT services upon awareness of HIV risk. A logistic regression model showed that females, those having little knowledge of HIV/AIDS, those unwilling to work with HIV-infected individuals, never having been tested for HIV and having low awareness regarding HIV risk were less willing to use VCT. Conclusions: The results of this study indicated that much greater efforts are needed to improve HIV/AIDS and VCT knowledge, to promote safer sex and to improve VCT acceptance among rural migrants in central China, particularly those engaging in risky behaviours.
Although HLA-B*57 (B57) is associated with slow progression to disease following HIV-1 infection, B57 heterozygotes display a wide spectrum of outcomes, including rapid progression, viremic slow progression, and elite control. Efforts to identify differences between B57-positive (B57+) slow progressors and B57+ rapid progressors have largely focused on cytotoxic T lymphocyte (CTL) phenotypes and specificities during chronic stages of infection. Although CTL responses in the early months of infection are likely to be the most important for the long-term rate of HIV-1 disease progression, few data on the early CTL responses of eventual slow progressors have been available. Utilizing the Multicenter AIDS Cohort Study (MACS), we retrospectively examined the early HIV-1-specific CTL responses of 14 B57+ individuals whose time to development of disease ranged from 3.5 years to longer than 25 years after infection. In general, a greater breadth of targeting of epitopes from structural proteins, especially Gag, as well as of highly conserved epitopes from any HIV-1 protein, correlated with longer times until disease. The single elite controller in the cohort was an outlier on several correlations of CTL targeting and time until disease, consistent with reports that elite control is typically not achieved solely by protective HLA-mediated CTLs. When targeting of individual epitopes was analyzed, we found that early CTL responses to the IW9 (ISPRTLNAW) epitope of Gag, while generally subdominant, correlated with delayed progression to disease. This is the first study to identify early CTL responses to IW9 as a correlate of protection in persons with HLA-B*57.
To review the incidence of respiratory conditions and their effect on mortality in HIV-infected and uninfected individuals prior to and during the era of highly active antiretroviral therapy (HAART).
Two large observational cohorts of HIV-infected and HIV-uninfected men (Multicenter AIDS Cohort Study [MACS]) and women (Women’s Interagency HIV Study [WIHS]), followed since 1984 and 1994, respectively.
Adjusted odds or hazards ratios for incident respiratory infections or non-infectious respiratory diagnoses, respectively, in HIV-infected compared to HIV-uninfected individuals in both the pre-HAART (MACS only) and HAART eras; and adjusted Cox proportional hazard ratios for mortality in HIV-infected persons with lung disease during the HAART era.
Compared to HIV-uninfected participants, HIV-infected individuals had more incident respiratory infections both pre-HAART (MACS, odds ratio [adjusted-OR], 2.4; 95% confidence interval [CI], 2.2–2.7; p<0.001) and after HAART availability (MACS, adjusted-OR, 1.5; 95%CI 1.3–1.7; p<0.001; WIHS adjusted-OR, 2.2; 95%CI 1.8–2.7; p<0.001). Chronic obstructive pulmonary disease was more common in MACS HIV-infected vs. HIV-uninfected participants pre-HAART (hazard ratio [adjusted-HR] 2.9; 95%CI, 1.02–8.4; p = 0.046). After HAART availability, non-infectious lung diseases were not significantly more common in HIV-infected participants in either MACS or WIHS participants. HIV-infected participants in the HAART era with respiratory infections had an increased risk of death compared to those without infections (MACS adjusted-HR, 1.5; 95%CI, 1.3–1.7; p<0.001; WIHS adjusted-HR, 1.9; 95%CI, 1.5–2.4; p<0.001).
HIV infection remained a significant risk for infectious respiratory diseases after the introduction of HAART, and infectious respiratory diseases were associated with an increased risk of mortality.
Dosage of methadone maintenance therapy (MMT) is an important factor influencing retention in methadone treatment. MMT clients in China received lower dosages of methadone compared with those provided in other countries. The objective of this study is to elucidate the reason for the low methadone dosage prescribed in MMT clinics in China.
Twenty-eight service providers were recruited from the MMT clinics in Zhejiang and Jiangxi Provinces, China. Qualitative in-depth interviews were conducted to ascertain the procedure for prescribing methadone in the MMT clinics.
The average dosage prescribed in the 28 clinics was 35 mg per person per day. Four major themes resulting in low dosage of methadone were identified: (1) the service providers fear the liability resulting from large doses of methadone in combination with other substances which might result in overdose fatalities, (2) lack of understanding of harm reduction which resulted in low acceptance of the long term maintenance treatment approach, (3) break-down in communication between clients and service providers about dosage adjustment, and (4) dosage reduction is perceived by most service providers as an effective way to treat the side-effects associated with MMT.
The findings of the study highlighted the necessity to formulate clear guidelines concerning individualized dosage management and to improve training among service providers’ in MMT clinics in China.
Methadone maintenance therapy; China; opioid use; dosage; qualitative study
Asymptomatic Chlamydia trachomatis (chlamydia) and Neisseria gonorrhoeae (gonorrhea) infections pose diagnostic and control problems in developing countries.
Participants in China, India, Peru, Russia, and Zimbabwe were screened for C. trachomatis and N. gonorrhoeae infections and symptoms.
A total of 18,014 participants were evaluated at baseline, 15,054 at 12 months, and 14,243 at 24 months. The incidence of chlamydia in men was 2.0 per 100 person years both from baseline to 12 months and from 12 to 24 months, and in women, 4.6 from baseline to 12 months and 3.6 from 12 to 24 months; a range of 31.2% to 100% reported no symptoms across the 5 countries. The incidence of gonorrhea in men was 0.3 per 100 person years both from baseline to 12 months and from 12 to 24 months, and in women, 1.4 from baseline to 12 months and 1.1 from 12 to 24 months; a range of 66.7% to 100% reported no symptoms. Being female, aged 18 to 24 years, and having more than 1 partner were associated with both the infections. In addition, being divorced, separated, or widowed was associated with gonorrhea. Being male, having 6+ years of education, and reporting only 1 partner were associated with having no symptoms among those infected with chlamydia. No variables correlated with asymptomatic gonorrhea among those infected.
A high prevalence and incidence of asymptomatic sexually transmitted infections was identified among men and women in a wide variety of settings. More effective programs are needed to identify and treat chlamydia and gonorrhea infections, especially among women, young adults, those with multiple partners, those repeatedly infected, and particularly those at risk without symptoms. The risk of transmission from persons with no symptoms requires further study.
Contact tracing is especially useful for identifying an infection with few cases in the population, such as HIV in China. Little such research is available in China.
Every newly diagnosed HIV case from 2008–2010 in Taizhou Prefecture, Zhejiang Province in China, was invited to participate as an “index case” in a contact tracing survey by providing contact information for up to eight sexual contacts who themselves were approached for voluntary HIV counseling and testing (VCT). Those who tested HIV-positive were then subjected to another contact tracing survey. This process was repeated until no more sexual contacts were reported or tested positive.
A total of 463 HIV-infected individuals were newly identified during the study period, including 338 cases who were identified from routine surveillance programs and 125 cases who were identified from the present contact tracing survey. Among these 463 cases, 398 (86.0%) served as ‘index cases’ in the survey, including 290 (85.8%) out of the 338 cases identified from routine surveillance programs and 108 (86.4%) out of the 125 cases identified from the present survey. These 398 ‘index cases’ reported a total of 1,403 contactable sexual contacts, of whom 320 (22.8%) received HIV testing and 125 (39.1%) tested positive for HIV. Willingness to receive HIV testing was high among spouses and long term heterosexual or homosexual partners but extremely low among casual and commercial sex partners of ‘index cases’. Consistent condom use was rare for all participants. A total of 290 independent sexual network components were constructed, with high complexity.
Contact tracing is useful for identifying new HIV infections from spouses or long term sexual partners of HIV-infected individuals. The complicated sexual networks existing between and beyond HIV-infected persons provide opportunities for rapid spread of HIV in such areas.
Contact tracing; Sexual behavior; Sexual networks; HIV testing; HIV infection
Methadone maintenance therapy (MMT) in China is facing challenges such as high relapse rates and low coverage. The study assessed factors influencing MMT utilization among opiate users. In-depth interviews were conducted among 30 opiate users in 2008 to ascertain the barriers against seeking MMT. Data were analyzed using ATLAS.ti. Barriers to the treatment included requirement of registration with police, perceived discrimination, logistic difficulties, side effects, fear of being addicted to another drug, lack of additional services, and economic burden. The result suggests the need for structural changes such as improving comprehensive services, simplifying application procedure, and enhancing referral system. The study's limitations are noted.
methadone maintenance therapy; China; qualitative; opiate users; HIV/AIDS
The risk of developing non-Hodgkin lymphoma (NHL) is greatly increased in HIV infection. The aim of this study was to determine if elevated serum levels of molecules associated with B cell activation precede the diagnosis of AIDS-associated NHL.
Serum levels of B cell activation-associated molecules, interleukin-6 (IL6), interleukin-10 (IL10), soluble CD23 (sCD23), soluble CD27 (sCD27), soluble CD30 (sCD30), C-reactive protein (CRP), and IgE were determined in 179 NHL cases and HIV+ controls in the Multicenter AIDS Cohort Study, collected at up to three time points per subject, 0–5 years prior to AIDS-NHL diagnosis.
Serum IL6, IL10, CRP, sCD23, sCD27, and sCD30 levels were all significantly elevated in the AIDS-NHL group, when compared to HIV+ controls or to AIDS controls, after adjusting for CD4 T cell number. Elevated serum levels of B cell activation-associated molecules were seen to be associated with the development of systemic (non-CNS) NHL, but not with the development of primary CNS lymphoma.
Levels of certain B cell stimulatory cytokines and molecules associated with immune activation are elevated for several years preceding the diagnosis of systemic AIDS-NHL. This observation is consistent with the hypothesis that chronic B cell activation contributes to the development of these hematologic malignancies.
Marked differences in serum levels of several molecules are seen for several years pre-diagnosis in those who eventually develop AIDS-NHL. Some of these molecules may serve as candidate biomarkers and provide valuable information to better define the etiology of NHL.
lymphoma; B cell; cytokines; AIDS; immune activation
We show that microRNA-21 is significantly elevated in peripheral B cells of HIV infected individuals who go on to develop AIDS-NHL (n=13, < 3 yrs prior to diagnosis) when compared to HIV negative (n = 18) or HIV positive controls (n = 21) (p < 0.01). Moreover, miR-21 is overex-pressed in activated B cells, and can be induced by IL4 alone, or with CD40 or IgM costimulation, and lipopolysaccharides (LPS), suggesting that miR-21 may help maintain B-cell hyperactivation, contributing to lymphomagenesis.
We examined an at-risk population in China, money boys (MBs), to evaluate their potential role for transmitting HIV and sexually transmitted infections (STIs). Data were collected from 418 MBs selected by time-location cluster sampling, using a self-administered computerized questionnaire and testing a small blood sample for HIV/STIs. One-third (32.1%) of participants self-identified as homosexual, 25.4% heterosexual, 33.5% bisexual, and 9.1% uncertain. Consistent condom use by participants was 70–80% with commercial sex partners, 43.9% with girlfriends, and 60–70% with other non-commercial partners. HIV prevalence was 3.3%; syphilis, 10.5%; and HSV-2, 11.0%; overall prevalence for any was 20.3%. Factors significantly associated with HIV/STIs included being minority (OR = 4.82), having only male partners (OR = 1.92), having more male casual partners in the last 6 months (OR = 1.28), being younger at sexual debut (OR = 1.14), and being older (OR = 1.11). This study emphasizes the importance of developing targeted interventions for MBs, particularly those who are homosexual or minority.
Money boys; Male sex workers; HIV; Sexually transmitted infections (STIs); Condom use; Risk factors; China
The major mode of HIV/AIDS transmission in China is now heterosexual activities, but risk for HIV and sexually transmitted diseases (STDs) may differ among different strata of female sex workers (FSWs). Respondent-driven sampling was used to recruit 320 FSWs in Guangdong Province, China. The respondents were interviewed using a structured questionnaire, and tested for HIV, syphilis, gonorrhea, and Chlamydia. The street-based FSWs had lower education levels, a higher proportion supporting their families, charged less for their services, and had engaged in commercial sex for a longer period of time than establishment-based FSWs. The proportion consistently using condoms with clients and with regular non-paying partners was also lower. The prevalence of syphilis, gonorrhea, and Chlamydia was higher among street-based sex workers. Being a street-based sex worker, having regular non-paying sex partners, and having non-regular non-paying partners were independent risk factors for inconsistent condom. Street-based FSWs had more risk behaviors than establishment-based FSWs, and should therefore be specifically targeted for HIV as well as STD intervention programs.
Behavior; HIV/AIDS; HIV; STD; Female sex workers
Money boys (MBs) who typically sell sex to males have not yet been extensively studied in China. In this 2009 study, 28 venue-based MBs were interviewed. We analyzed their condom use behaviors with various partners, including male and female clients, male and female casual partners, other MBs and female sex workers, and boyfriends and girlfriends. All participants were aware of the need for using condoms; however, usage with different partner types varied. The longer a relationship with a partner, the less frequent was condom use. A major reason for not using condoms was that they or their partners did not like the loss of sensation due to condom use. Other factors included sexual orientation, age, duration in commercial sex, concerns about HIV/AIDS, attractiveness of partners, and support of “mommies” (brothel supervisors). Both individual- and venue-level interventions are needed to promote condom use, and mommies need to be included in intervention strategies.
We investigated associations between stress and mental health (positive affect, depressive symptoms) among HIV-negative and HIV-positive midlife and older gay-identified men, along with the mediating and moderating effects of mastery and emotional support. We also studied the mental health effects of same-sex marriage.
We obtained data from self-administered questionnaires completed in 2009 or 2010 by a subsample (n=202; average age=56.91 years; age range= 44–75 years) of participants in the University of California, Los Angeles component of the Multicenter AIDS Cohort Study, one of the largest and longest-running natural-history studies of HIV/AIDS in the United States.
Both sexual minority stress (perceived gay-related stigma, excessive HIV bereavements) and aging-related stress (independence and fiscal concerns) appeared to have been detrimental to mental health. Sense of mastery partially mediated these associations. Being legally married was significantly protective net of all covariates, including having a domestic partner but not being married. Education, HIV status, and race/ethnicity had no significant effects.
Sexual minority and aging-related stress significantly affected the emotional lives of these men. Personal sense of mastery may help to sustain them as they age. We observed specific mental health benefits of same-sex legal marriage.
Chronic inflammation and B-cell hyperactivation are seen in HIV infection, contributing to an increased risk for the accrual of genetic errors that may result in B-cell lymphoma. The primary objective of this study was to determine the effect of highly active antiretroviral therapy (HAART) on serum levels of molecules that are associated with immune activation and/or inflammation, including several that are associated with B-cell activation, specifically IL-6, sCD30, sCD27, IgG, IgA, CXCL13 (B lymphocyte chemoattractant, BLC), a B-lymphocyte chemokine involved in B-cell trafficking, as well as C-reactive protein, an acute-phase protein.
We used a retrospective cohort study design, measuring serum levels of these markers at each of four 1-year intervals, 2 years before and 2 years after HAART initiation, in a subgroup of 290 HIV-infected men enrolled in the Multicenter AIDS Cohort Study (MACS).
Serum levels of immune activation-associated molecules were measured by ELISA and multiplexed immunometric assays. Reference values were determined by the 5th to 95th percentiles from a sample of 109 HIV-uninfected MACS men.
HAART use was associated with a reduction, but not normalization, of most biomarkers tested. Serum levels of IL-6 and C-reactive protein appeared to be unaffected by HAART.
These results suggest a partial normalization of serum cytokine levels post HAART. However, a chronic state of B-cell hyperactivation continues 2–3 years after HAART initiation. These findings may explain, in part, the excess incidence of lymphoma still occurring in HIV-infected persons in the post-HAART era.
activation; AIDS; antiretroviral therapy; B lymphocytes; highly active; HIV; non-Hodgkin’s lymphoma
Background.The HLA class II molecules play a central role in the generation of human immunodeficiency virus (HIV)–specific CD4+ T-helper cells, which are critical for the induction of cytotoxic CD8+ T cell responses. However, little is known about the impact of HLA class II alleles on HIV disease progression.
Methods.In this study we investigated the effect of HLA class II alleles on HIV disease outcome and HIV-specific T cell responses in a cohort of 426 antiretroviral therapy–naive, HIV-1 clade C–infected, predominantly female black South Africans.
Results.The HLA class II allele DRB1*1303 was independently associated with lower plasma viral loads in this population (P = .02), an association that was confirmed in a second cohort of 1436 untreated, HIV-1 clade B–infected, male European Americans, suggesting that DRB1*1303-mediated protection is independent of ethnicity, sex, and viral clade. Interestingly, DRB1*1303 carriage was not associated with an increased frequency of interferon (IFN) γ–positive HIV-specific CD4+ T cell responses.
Conclusions.These data demonstrate the independent effect of an HLA class II allele, DRB1*1303, on HIV disease progression, in the absence of increased IFN-γ–positive HIV-specific CD4+ T cell frequencies, suggesting that the protective activity of DRB1*1303 may be mediated via an alternative mechanism.
Adenoviruses are among the most promising vectors for the development of an HIV vaccine. The results of the phase IIB study of the adenovirus serotype 5-based Merck Trivalent HIV vaccine have raised the concern that serological immunity to Ad5 could be linked to HIV acquisition risk in high-risk individuals. We examined the association between adenovirus serostatus and the rate of incident HIV infection in populations at elevated risk of HIV acquisition.
We performed a nested case-control study of Ad5 serostatus among 299 HIV-infected and 590 matched HIV-uninfected persons participating in MACS and in HPTN 039, a study of HSV-2 suppression among adults in the U.S., South America and Africa. Appropriate HIV cases and controls were identified in each cohort, and Ad5 neutralizing antibody titers were compared in these two groups.
In MACS and HPTN 039, the relative risks of incident HIV infection among Ad5 seropositive vs. Ad5 seronegative individuals were 1.1 (95% CI 0.8–1.5, p = 0.57) and 1.0 (95% CI 0.4 – 2.3, p = 0.99) respectively. HIV-1 acquisition rates did not vary significantly by Ad5 neutralizing antibody titer.
The presence of Ad5 neutralizing antibodies is not linked to the risk of HIV acquisition among populations at elevated risk of HIV infection.
Adenovirus; serology; MSM; HIV; acquisition risk; vaccine