Adjusting Incidence Estimates with Laboratory Test Performances: A Pragmatic Maximum Likelihood Estimation-Based Approach.

Understanding the incidence of disease is often crucial for public policy decision-making, as observed during the COVID-19 pandemic. Estimating incidence is challenging, however, when the definition of incidence relies on tests that imperfectly measure disease, as in the case when assays with variable performance are used to detect the SARS-CoV-2 virus. To our knowledge, there are no pragmatic methods to address the bias introduced by the performance of labs in testing for the virus. In the setting of a longitudinal study, we developed a maximum likelihood estimation-based approach to estimate laboratory performance-adjusted incidence using the expectation-maximization algorithm. We constructed confidence intervals (CIs) using both bootstrapped-based and large-sample interval estimator approaches. We evaluated our methods through extensive simulation and applied them to a real-world study (TrackCOVID), where the primary goal was to determine the incidence of and risk factors for SARS-CoV-2 infection in the San Francisco Bay Area from July 2020 to March 2021. Our simulations demonstrated that our method converged rapidly with accurate estimates under a variety of scenarios. Bootstrapped-based CIs were comparable to the large-sample estimator CIs with a reasonable number of incident cases, shown via a simulation scenario based on the real TrackCOVID study. In more extreme simulated scenarios, the coverage of large-sample interval estimation outperformed the bootstrapped-based approach. Results from the application to the TrackCOVID study suggested that assuming perfect laboratory test performance can lead to an inaccurate inference of the incidence. Our flexible, pragmatic method can be extended to a variety of disease and study settings.

Identifying Paucisymptomatic or Asymptomatic and Unrecognized Ebola Virus Disease Among Close Contacts Based on Exposure Risk Assessments and Screening Algorithms.

BACKGROUND: There is limited evidence to evaluate screening algorithms with rapid antigen testing and exposure assessments as identification strategies for paucisymptomatic or asymptomatic Ebola virus (EBOV) infection and unrecognized EBOV disease (EVD). METHODS: We used serostatus and self-reported postexposure symptoms from a cohort study to classify contact-participants as having no infection, paucisymptomatic or asymptomatic infection, or unrecognized EVD. Exposure risk was categorized as low, intermediate, or high. We created hypothetical scenarios to evaluate the World Health Organization (WHO) case definition with or without rapid diagnostic testing (RDT) or exposure assessments. RESULTS: This analysis included 990 EVD survivors and 1909 contacts, of whom 115 (6%) had paucisymptomatic or asymptomatic EBOV infection, 107 (6%) had unrecognized EVD, and 1687 (88%) were uninfected. High-risk exposures were drivers of unrecognized EVD (adjusted odds ratio, 3.5 [95% confidence interval, 2.4-4.9]). To identify contacts with unrecognized EVD who test negative by the WHO case definition, the sensitivity was 96% with RDT (95% confidence interval, 91%-99%), 87% with high-risk exposure (82%-92%), and 97% with intermediate- to high-risk exposures (93%-99%). The proportion of false-positives was 2% with RDT and 53%-93% with intermediate- and/or high-risk exposures. CONCLUSION: We demonstrated the utility and trade-offs of sequential screening algorithms with RDT or exposure risk assessments as identification strategies for contacts with unrecognized EVD.

Anatomy of a Hotspot: Chain and Seroepidemiology of Ebola Virus Transmission, Sukudu, Sierra Leone, 2015-16.

Studies have yet to include minimally symptomatic Ebola virus (EBOV) infections and unrecognized Ebola virus disease (EVD) in Ebola-related transmission chains and epidemiologic risk estimates. We conducted a cross-sectional, sero-epidemiological survey from October 2015 to January 2016 among 221 individuals living in quarantined households from November 2014 to February 2015 during the Ebola outbreak in the village of Sukudu, Sierra Leone. Of 48 EBOV-infected persons, 25% (95% confidence interval [CI], 14%-40%) had minimally symptomatic EBOV infections and 4% (95% CI, 1%-14%) were unrecognized EVD cases. The pattern of minimally symptomatic EBOV infections in the transmission chain was nonrandom (P < .001, permutation test). Not having lived in the same house as an EVD case was significantly associated with minimally symptomatic infection. This is the first study to investigate a chain of EBOV transmission inclusive of minimally symptomatic EBOV infections and unrecognized EVD. Our findings provide new insights into Ebola transmission dynamics and quarantine practices.

Symptoms of Depression in People Living with HIV in Ho Chi Minh City, Vietnam: Prevalence and Associated Factors.

This cross-sectional study investigated the prevalence and correlates of symptoms of depression among 400 people living with HIV/AIDS (PLHIV) from two HIV clinics in Ho Chi Minh City, Vietnam. Based on the Center for Epidemiologic Studies-Depression scale, 36.5% of participants were classified as likely to be clinically depressed. Factors independently associated with symptoms of depression included self-report of poor or fair health (aOR 2.16, 95% CI 1.33-3.51), having a low body mass index (aOR 1.85, 95% CI 1.13-3.04), reporting recent problems with family (aOR 1.97, 95% CI 1.21-3.19), feeling shame about being HIV-infected (aOR 1.90, 95% CI 1.20-3.00), and reporting conflict with a partner (aOR 2.21, 95% CI 1.14-4.26). Participants who lived with family (aOR 0.48, 95% CI 0.25-0.90) or who received emotional support from their families or supportive HIV networks (aOR 0.45, 95% CI 0.25-0.80) were less likely to experience symptoms of depression. Screening for and treatment of depression among Vietnamese PLHIV are needed.

Characterization of HIV Recent Infection Among High-Risk Men at Public STI Clinics in Mumbai.

We examined associations with HIV recent infection and estimated transmitted drug resistance (TDR) prevalence among 3345 men at sexually transmitted infection clinics in Mumbai (2002-2005). HIV seroincidence was 7.92% by the BED-CEIA and was higher at a clinic located near brothels (12.39%) than at a hospital-based clinic (3.94%). HIV recent infection was associated with a lifetime history of female sex worker (FSW) partners, HSV-2, genital warts, and gonorrhea. TDR prevalence among recent infection cases was 5.7%. HIV testing services near sex venues may enhance case detection among high-risk men who represent a bridging population between FSWs and the men's other sexual partners.

The Relationship Between Spirituality/Religiousness and Unhealthy Alcohol Use Among HIV-Infected Adults in Southwestern Uganda.

HIV and alcohol use are two serious and co-existing problems in sub-Saharan Africa. We examined the relationship between spirituality and/or religiousness (SR) and unhealthy alcohol use among treatment-naïve HIV-infected adults attending the HIV clinic in Mbarara, Uganda. Unhealthy alcohol was defined as having either an alcohol use disorders identification test-consumption score of ≥4 for men or ≥3 for women, or having a phosphatidylethanol level of ≥50 ng/ml based on analysis of dried bloodspot specimens. Of the 447 participants, 67.8% were female; the median age was 32 years (interquartile range [IQR] 27-40). About half reported being Protestant (49.2%), 35.1% Catholic, and 9.2% Muslim. The median SR score was high (103 [IQR 89-107]); 43.3% drank at unhealthy levels. Higher SR scores were associated with lower odds of unhealthy drinking (adjusted odds ratio [aOR]: 0.83 per standard deviation [SD] increase; 95% confidence interval [CI] 0.66-1.03). The "religious behavior" SR subscale was significantly associated with unhealthy alcohol use (aOR: 0.72 per SD increase; 95% CI 0.58-0.88). Religious institutions, which facilitate expression of religious behavior, may be helpful in promoting and maintaining lower levels of alcohol use.

A longitudinal and case-control study of dropout among drug users in methadone maintenance treatment in Haiphong, Vietnam.

BACKGROUND: Vietnam began providing methadone maintenance therapy (MMT) in 2008; as of June 2016, 44,479 persons who inject drugs (PWID) were in treatment in 57 provinces. However, 10-23% of patients were estimated to have dropped out of treatment during the first 2 years. We evaluated dropout and factors associated with quitting treatment. METHODS: We followed clients ≥ 18 years old enrolled in five MMT clinics in Haiphong for 3 years. Persons who missed a consecutive month of methadone treatment were considered to have dropped out and were not allowed to return; those who missed greater than five consecutive doses were considered to be non-compliant but were allowed to restart treatment at their initial dose. Clients who dropped out or who were non-compliant during their third year of MMT (cases) were traced and matched with two clients who remained in treatment (controls) by gender, age, and length of time in the program. Cases and controls were interviewed. Additional data on levels of yearly retention were abstracted from clinic records. RESULTS: Among the 1055 patients initially enrolled in MMT, dropout and non-compliance combined was 13.6% during the first year, 16.5% during the second year, and 22.3% during the third year. By 36 months, 33.3% of clients had dropped out, of whom 10.6% had died and 24% had been arrested. We traced and interviewed 81 clients who dropped out or who were non-compliant during year 3 as well as 161 controls. The primary reasons for dropping out included claiming no dependence on heroin (22.2%), conflict with work (21.0%), health problems (16.0%), and inability to afford the methadone co-payment of approximately 0.5 USD/day (14.8%). Independent factors associated with non-compliance included continuing to use heroin (aOR = 12.4, 95% CI 4.2-36.8) and missing greater than three doses during the previous 3 months (aOR = 18.5, 95% CI 7.4-47.1); receiving a daily dose of > 120 mg of methadone was associated with a lower odds ratio of dropping out (aOR = 0.3, 95% CI 0.1-0.9). CONCLUSION: By 3 years, one third of all patients in treatment had permanently dropped out. Ensuring that methadone dosing is adequate and reducing or eliminating the co-payment fee for those who cannot afford it could improve retention.

University students and the risk of HIV and other sexually transmitted infections in Uganda: the Crane survey.

Adolescents and young adults are at high risk of human immunodeficiency virus (HIV) infection in sub-Saharan Africa. Previous reports have found that university students in Africa comprise a sexually active population, although the prevalence of HIV or sexually transmitted infections (STI) has not been measured. We conducted a cross-sectional survey of students from five large universities in Kampala, Uganda, using respondent-driven sampling. We asked students to complete behavioral questionnaires and provide biological samples to test for HIV, Chlamydia trachomatis, Neisseria gonorrhoeae, Treponema pallidum, Trichomonas vaginalis, and bacterial vaginosis. We enrolled 649 students and obtained interpretable data from 640. Around 50% of the respondents were male, and the mean age was 22 years. An estimated 0.8% (95% CI 0.0-2.0) of male students had Chlamydia infection, approximately 4.3% (95% CI 2.0-7.0) had syphilis, 0.4% (95% CI 0.0-0.9) had HIV, and none had gonorrhea. An estimated 32.6% (95% CI 22.4-40.8) of women had bacterial vaginosis, 2.5% (95% CI 0.7-6.3) had Chlamydia infection, 1.7% (95% CI 0.5-3.6) had syphilis, 1.0% (95% CI 0.0-2.4) had gonorrhea, 0.9% (95% CI 0.0-4.2) had trichomoniasis, and 0.9% (95% CI 0.0-1.8) had HIV. We found no significant risk factors for HIV or other STI among males. We also found that not using a condom during the latest sexual intercourse was significantly associated with HIV infection, other STI, or bacterial vaginosis (OR 2.16; 95% 1.26-3.78) among females. We conclude that while university students are sexually active and there is substantial risk for syphilis, there is little evidence of substantially increased HIV risk among them.

Prevalence and determinants of post-acute sequelae of COVID-19 in Liberia.

BACKGROUND: Evidence from resource-rich settings indicates that many people continue to have persistent symptoms following acute SARS-CoV-2 infection, called post-acute sequelae of COVID-19 (PASC). Only a few studies have described PASC in sub-Saharan Africa (SSA). We aimed to describe PASC in Liberia. METHODS: We randomly sampled all people who were reported from the most populous county to the Liberian Ministry of Health (MOH) as having a laboratory-confirmed SARS-CoV-2 infection from June to August 2021. We interviewed individuals by phone 3 to 6 months later. Those with persistence of at least one symptom were considered to have PASC. RESULTS: From among 2848 people reported to the MOH from Montserrado County during the period of interest, we randomly selected 650; of these, 548 (84.3%) were reached and 505 (92.2%) of those who were contacted were interviewed. The median age was 38 years (interquartile range (IQR), 30-49), and 43.6% were female. During acute infection, 40.2% were asymptomatic, 53.9% had mild/moderate disease and 6.9% had severe/critical disease. Among the 59.8% (n = 302) who were initially symptomatic, 50.2% (n = 152) reported at least one persistent symptom; the most common persistent symptoms were fatigue (21.2%), headache (16.2%) and cough (12.6%); 40.1% reported that PASC significantly affected their daily activities. Being hospitalized with moderate disease [adjusted prevalence ratio (aPR), 2.00 (95% CI, 1.59 to 2.80] or severe/critical disease [aPR, 2.11 (95% CI, 1.59 to 2.80)] was associated with PASC, compared with those not hospitalized. Females were more likely than males to report persistent fatigue [aPR, 1.67 (95% CI, 1.08 to 2.57)]. CONCLUSIONS: Our findings suggest that persistent symptoms may have affected a large proportion of people with initially symptomatic COVID-19 in west Africa and highlight the need to create awareness among infected people and health care professionals.

Virological surveillance of influenza-like illness among children in Ghana, 2008-2010.

BACKGROUND: The global annual attack rate for influenza is estimated to be 10%-20% in children, although limited information exists for Africa. In 2007, Ghana initiated influenza surveillance by routine monitoring of acute respiratory illness to obtain data on circulating strains. We describe influenza surveillance in children <11 years old who had influenza-like illness (ILI) from January 2008 to December 2010. METHODS: Oropharyngeal swabs from pediatric outpatients with ILI attending any of 22 health facilities across the country were submitted. We tested swabs for influenza virus using molecular assays, virus isolation, and hemagglutination assays. RESULTS: Of the 2810 swabs, 636 (23%) were positive for influenza virus. The percentage of positives by gender was similar. The proportion of ILI cases positive for influenza increased with age from 11% (31/275) in infants (aged 0-1 years) to 31% (377/1219) among children aged 5-10 years (P < .001). The majority of cases were influenza A (90%), of which 60% were influenza A(H1N1)pdm09. In all 3 years, influenza activity appeared slightly higher during May through July. CONCLUSIONS: During the 3 years of influenza surveillance in Ghana, children aged <11 years bore a high burden of influenza-associated ILI.

Association of protective behaviors with SARS-CoV-2 infection: results from a longitudinal cohort study of adults in the San Francisco Bay Area.

PURPOSE: In an effort to decrease transmission during the first years of the COVID-19 pandemic, public health officials encouraged masking, social distancing, and working from home, and restricted travel. However, many studies of the effectiveness of these measures had significant methodologic limitations. In this analysis, we used data from the TrackCOVID study, a longitudinal cohort study of a population-based sample of 3846 adults in the San Francisco Bay Area, to evaluate the association between self-reported protective behaviors and incidence of SARS-CoV-2 infection. METHODS: Participants without SARS-CoV2 infection were enrolled from August to December 2020 and followed monthly with testing and surveys (median of four visits). RESULTS: A total of 118 incident infections occurred (3.0% of participants). At baseline, 80.0% reported always wearing a mask; 56.0% avoided contact with nonhousehold members some/most of the time; 9.6% traveled outside the state; and 16.0% worked 20 or more hours per week outside the home. Factors associated with incident infection included being Black or Latinx, having less than a college education, and having more household residents. The only behavioral factor associated with incident infection was working outside the home (adjusted hazard ratio 1.62, 95% confidence interval 1.02-2.59). CONCLUSIONS: Focusing on protecting people who cannot work from home could help prevent infections during future waves of COVID-19, or future pandemics from respiratory viruses. This focus must be balanced with the known importance of directing resources toward those at risk of severe infections.

The provision and utilization of essential health services in Afghanistan during COVID-19 pandemic.

Introduction: The COVID-19 pandemic has disrupted provision of essential health services and overwhelmed even robust health systems worldwide. The Afghanistan health system has suffered both from the pandemic, as well as from political upheaval and regime change. Methods: We evaluated essential service delivery using data collected from a cross-sectional survey of health care facilities in Afghanistan based on administration of a World Health Organization standardized assessment of frontline service readiness. A multi-stage sampling scheme was used to identify a representative sample of 92 health facilities (68 clinics and 24 hospitals) providing essential health services in five provinces. Facility managers were asked to report on changes in health service delivery in late 2021 and early 2022 (corresponding to the end of a significant national COVID-19 surge in infections) compared to the same period one year earlier. Results: Among health facilities evaluated; 29 were in urban and 63 were in rural settings. Most facilities reported an increase in the provision of outpatient care particularly in maternal and child health services as well as for tuberculosis, chronic respiratory diseases, mental health, and substance abuse; the number of in-patients also increased. In contrast, provision of services for malaria, neglected tropical diseases, and community outreach programs decreased. Nearly all facilities used strategies to maintain services, including targeting high-risk patients, promoting self-care, and redirecting patients to alternative health care sites. Nearly three fourth (70.6%) of facilities provided no training about COVID-19 to staff; only 65.2% referred COVID-19 patients to designated hospitals and 44.6% had safe transportation for these patients. Discussion: Increased demand for services during this period was likely due to a backlog in need generated during the preceding COVID-19 surge and the political changes happened a few months earlier to this survey. Facilities used various methods to maintain services, although the decrease in provision of community outreach was concerning. Facilities appeared to be able to maintain essential health services, despite an increase in demand. However, awareness and training of COVID-19 protocols and appropriate and safe referrals need to be improved. In general, these series of surveys are informative and helpful to identify any changes in provision of essential health services and can facilitate recovery of health systems during and after pandemics.

Attitudes Toward Gender-Based Violence Among Sexually Active Adult Men at High Risk for HIV in Rustenburg, South Africa.

Gender-based violence (GBV) toward women is widespread and has been associated with increased HIV risk. We investigated attitudes toward GBV among men living in Rustenburg, South Africa, who were enrolled in a longitudinal HIV incidence study. Participants were 18 to 49 years old, reported high risk sexual activity in the last 3 months, and were HIV-uninfected. Attitudes toward GBV were evaluated using responses to a five-item standardized questionnaire about men perpetrating physical violence on a female spouse; responses to each item were scaled from 1 (no agreement) to 4 (strong agreement) and summed. Total scores >10 were considered permissive toward GBV. Among the 535 men analyzed, nearly half (N = 229, 42.8%) had a GBV score >10. Being young (18-24 years) (adjusted odds ratio [aOR] = 1.53, 95% confidence interval [CI] [1.06, 2.22]), having less years of education (aOR = 1.61, 95% CI [1.11, 2.32]), and reporting no current sexual partner at baseline (aOR = 2.10, 95% CI [1.06, 4.14]) were independently associated with permissive attitudes toward GBV. The following behaviors reported in the last 3 months were also associated with high GBV scores: having a new female partner (aOR = 1.78, 95% CI [1.02, 3.10]), and having had an STI (aOR = 1.85, 95% CI [1.15, 2.99]). Consuming alcohol prior to sex in the last month (aOR = 1.59, 95% CI [1.09, 2.31]) was also associated with high GBV scores. A large proportion of South African HIV-uninfected men in this analysis reported permissive attitudes toward GBV. These attitudes were associated with HIV risk behavior. Integrating GBV and HIV prevention programs is essential.

Design of a population-based longitudinal cohort study of SARS-CoV-2 incidence and prevalence among adults in the San Francisco Bay Area.

PURPOSE: We describe the design of a longitudinal cohort study to determine SARS-CoV-2 incidence and prevalence among a population-based sample of adults living in six San Francisco Bay Area counties. METHODS: Using an address-based sample, we stratified households by county and by census-tract risk. Risk strata were determined by using regression models to predict infections by geographic area using census-level sociodemographic and health characteristics. We disproportionately sampled high and medium risk strata, which had smaller population sizes, to improve precision of estimates, and calculated a desired sample size of 3400. Participants were primarily recruited by mail and were followed monthly with PCR testing of nasopharyngeal swabs, testing of venous blood samples for antibodies to SARS-CoV-2 spike and nucleocapsid antigens, and testing of the presence of neutralizing antibodies, with completion of questionnaires about socio-demographics and behavior. Estimates of incidence and prevalence will be weighted by county, risk strata and sociodemographic characteristics of non-responders, and will take into account laboratory test performance. RESULTS: We enrolled 3842 adults from August to December 2020, and completed follow-up March 31, 2021. We reached target sample sizes within most strata. CONCLUSIONS: Our stratified random sampling design will allow us to recruit a robust general population cohort of adults to determine the incidence of SARS-CoV-2 infection. Identifying risk strata was unique to the design and will help ensure precise estimates, and high-performance testing for presence of virus and antibodies will enable accurate ascertainment of infections.

Prevalence and factors associated with hypertension among people living with HIV/AIDS on antiretroviral therapy in Uganda.

INTRODUCTION: antiretroviral therapy (ART) has improved survival of People Living with HIV (PLWH); however, this has resulted in an increasingly high prevalence of non-communicable diseases (NCD) like hypertension. Hypertension is a major risk factor for cardiovascular and cerebral vascular disease, which are both associated with high morbidity and mortality rates. We studied the prevalence and factors associated with hypertension among PLWH on ART. METHODS: we conducted a retrospective data analysis of PLWH on ART enrolled between 2011 and 2014 into a randomized double-blinded placebo-controlled trial investigating the safety of discontinuing cotrimoxazole prophylaxis (COSTOP) among PLWH in Central Uganda. We used the mean blood pressure (BP) measurements of the first four monthly clinic visits to define hypertension. Patients were categorised as: having normal BP (≤120/80mmHg), elevated BP (systolic >120-129, and diastolic ≤80), Stage 1 hypertension (systolic 130-139, or diastolic >80-89) and Stage 2 hypertension (systolic ≥140 or diastolic ≥90). Multiple logistic regression was used to evaluate factors associated with hypertension. RESULTS: data from 2026 COSTOP trial study participants were analysed, 74.1% were women and 77.2% were aged 35 years and above. The overall prevalence of hypertension was 29%, of whom 19.5% had Stage 1 hypertension and 9.5% had Stage 2 hypertension. About 21.4% were overweight or obese. Factors independently associated with hypertension among PLWH on ART included increasing age (p≤0.001) and high body mass index (p≤0.001). Efavirenz (p≤0.001) and lopinavir/ritonavir (p=0.036) based regimen had lower odds of hypertension than Nevirapine based regimens. CONCLUSION: PLWH on ART have a high prevalence of hypertension, which rises with increasing age and body mass index (BMI) and among those on nevirapine-based ART. Implementation of hypertension prevention measures among PLWH on ART and integration of NCD and HIV care to improve patients' management outcomes are required.

Race-ethnicity and COVID-19 Vaccination Beliefs and Intentions: A Cross-Sectional Study among the General Population in the San Francisco Bay Area.

OBJECTIVE: The study was designed to compare intentions to receive COVID-19 vaccination by race-ethnicity, to identify beliefs that may mediate the association between race-ethnicity and intention to receive the vaccine and to identify the demographic factors and beliefs most strongly predictive of intention to receive a vaccine. DESIGN: Cross-sectional survey conducted from November 2020 to January 2021, nested within a longitudinal cohort study of the prevalence and incidence of SARS-CoV-2 among a general population-based sample of adults in six San Francisco Bay Area counties (called TrackCOVID). Study Cohort: In total, 3161 participants among the 3935 in the TrackCOVID parent cohort responded. RESULTS: Rates of high vaccine willingness were significantly lower among Black (41%), Latinx (55%), Asian (58%), Multi-racial (59%), and Other race (58%) respondents than among White respondents (72%). Black, Latinx, and Asian respondents were significantly more likely than White respondents to endorse lack of trust of government and health agencies as a reason not to get vaccinated. Participants' motivations and concerns about COVID-19 vaccination only partially explained racial-ethnic differences in vaccination willingness. Concerns about a rushed government vaccine approval process and potential bad reactions to the vaccine were the two most important factors predicting vaccination intention. CONCLUSIONS: Vaccine outreach campaigns must ensure that the disproportionate toll of COVID-19 on historically marginalized racial-ethnic communities is not compounded by inequities in vaccination. Efforts must emphasize messages that speak to the motivations and concerns of groups suffering most from health inequities to earn their trust to support informed decision making.

Interferon gamma (IFN-γ) negative CD4+ and CD8+ T-cells can produce immune mediators in response to viral antigens.

Evaluation of antigen-specific T-cell responses to viral antigens is frequently performed on IFN-γ secreting cells. However, T-cells are capable of producing many more functions than just IFN-γ, some of which, like Perforin, are associated with immune protection in HIV-1 disease elite controllers. We evaluated the extent of missed T-cell functions when IFN-γ secretion is used as a surrogate marker for further evaluation of T-cell functions. Intracellular cytokine staining assay and flow cytometry were used to assess peripheral blood mononuclear cells (PBMCs) from 31 HIV-infected ART-naive individuals for the extent to which gated CD4+ and CD8+ IFN-γ producing and non-producing T-cells also secreted IL-2, Perforin, and TNF-α functions. Similarly, the extent of missed virus-specific responses in IFN-γ ELISpot assay negative T-cells from 5 HIV-1 uninfected individuals was evaluated. Cells from HIV-infected individuals were stimulated with pooled consensus group M (Con M) peptides; and those from healthy individuals were stimulated with pooled adenovirus (Ad) peptides. Overall, frequencies of virus-specific IFN-γ secreting CD4+ and CD8+ cells were low. Proportions of IFN-γ negative CD4+ expressing IL-2, Perforin, or TNF-α to Con M were significantly higher (5 of 7 functional profiles) than the corresponding IFN-γ positive CD4+ (0 of 7) T-cell phenotype, p = 0.02; Fisher's Exact test. Likewise, proportions of CD8+ T-cells expressing other functions were significantly higher in 4 of the 7 IFN-γ negative CD8+ T-cells. Notably, newly stimulated Perforin, identified as Perforin co-expression with IL-2 or TNF-α, was significantly higher in IFN-γ negative CD8+ T-cell than in the positive CD8+ T-cells. Using SEB, lower responses in IFN-γ positive cells were most associated with CD4+ than CD8+ T-cells. These findings suggest that studies evaluating immunogenicity in response to HIV and Adenovirus viral antigens should not only evaluate T-cell responsiveness among IFN-γ producing cells but also among those T-cells that do not express IFN-γ.

Retention of adults from fishing communities in an HIV vaccine preparedness study in Masaka, Uganda.

INTRODUCTION: People living in fishing communities around Lake Victoria may be suitable for enrolment in HIV prevention trials because of high HIV incidence. We assessed the ability to recruit and retain individuals from fishing communities into an HIV vaccine preparedness cohort study in Masaka, Uganda. METHODS: HIV high risk, sero-negative adults (18-49 years) were identified from four fishing villages bordering Lake Victoria through door-to-door HIV counselling and testing (HCT). Interested persons were referred for screening, enrolment, and quarterly follow-up visits at a study clinic located approximately 30-40 kilometres away. Repeat HCT, HIV risk assessment, and evaluation and treatment for sexually transmitted infections were provided. Rates of and factors associated with study dropout were assessed using Poisson regression models. RESULTS: A total of 940 participants were screened between January 2012 and February 2015, of whom 654 were considered for the analysis. Over a two-year follow-up period, 197 (30.1%) participants dropped out of the study over 778.9 person-years, a dropout rate of 25.3 / 100 person-years of observation. Dropout was associated with being female (aRR = 1.56, 95% confidence interval [CI] 1.12-2.18), being 18-24 years (aRR = 1.64; 95% CI 1.03-2.60) or being 25-34 years (aRR = 1.63; 95% CI 1.04-2.55) compared to being 35+ years; having no education (aRR = 2.02; 95% CI: 1.23-3.31); living in the community for less than one year (aRR = 2.22; 95% CI: 1.46-3.38), or 1-5 years (aRR = 1.68; 95% CI: 1.16-2.45), compared to more than five years. CONCLUSIONS: Our results suggest that individuals from fishing communities can be recruited and retained in longitudinal studies; however, intensified participant tracing may be necessary for women, younger volunteers, those who are less educated and new residents.

HIV incidence and predictors of inconsistent condom use among adult men enrolled into an HIV vaccine preparedness study, Rustenburg, South Africa.

INTRODUCTION: Understanding HIV incidence and risk behaviour among populations being considered for HIV vaccine studies is necessary for the appropriate design of trials. METHODS: Between May 2012 and June 2015, we recruited men aged 18-49 years from urban and peri-urban areas of Rustenburg, a mining town in the North West Province, South Africa. Men who reported HIV-risk behaviour were followed for nine to 12 months to determine HIV incidence and factors associated with condom use. RESULTS: A total of 400 HIV uninfected men were enrolled; 366 (91.5%) had at least one follow-up visit and were included in the analysis; 47.6% were under 25 years of age. HIV incidence was 1.9 per 100 person-years (95% CI: 0.79-4.56). Among heterosexual men (N = 339), 80.8% reported having vaginal intercourse with multiple partners in the past three months, among whom 74.1% reported inconsistent condom use. Sixty-eight percent reported vaginal intercourse with new female partners, of whom 40.6% reported inconsistent condom use. Over half (55.6%) of men who had sex with men (N = 27) reported anal intercourse with multiple male partners in the past three months, of whom 68.2% reported using condoms inconsistently. Men who had more than two female partners in the last three months (n = 121) were more likely to use condoms inconsistently (aOR 4.31, 95% CI: 1.34-13.8); in contrast, those with more than one new female sex partner (aOR 0.13, 94% CI 0.04-0.44), and whose sexual debut was after 19 years of age (aOR 0.39, 95% CI: 0.15-1.01) were less likely to use condoms inconsistently. CONCLUSION: HIV incidence was low and similar to other studies of heterosexual men in South Africa. To identify men at high risk for HIV for enrolment in prevention trials, future researchers may need to focus on those who report early sexual debut and who report having multiple sexual partners. Men in newer relationships appear to use condoms more frequently.