Cofactors for the acquisition of HIV-1 among heterosexual men: prospective cohort study of trucking company workers in Kenya

Methods for measuring short-term geographical mobility used in infectious disease research: a scoping review protocol

INTRODUCTION

Geographical mobility, the movement of individuals or populations, may increase an individual's risk of acquiring or transmitting infectious diseases, including HIV, tuberculosis, malaria and COVID-19. Many studies have collected information on short-term mobility through self-reported travel histories or using GPS trackers, but there has been no consistent conceptualisation and operationalisation of such geographical mobility in global health research. This protocol aims to describe and synthesise different approaches to measuring short-term mobility.

METHODS AND ANALYSIS

We will search three databases (PubMed, Embase and Global Health) for peer-reviewed articles. After removing duplicates, two reviewers will first screen the titles and abstracts and then proceed to full-text screening. We will include studies that measure mobility at the individual level in the context of infectious diseases, including clinical trials, epidemiological studies and analyses of register data. Additional articles for inclusion may be identified through review of references in selected papers. We will summarise the method of data collection (GPS trackers, cellphones, retrospective self-report, travel journal, etc) and the specific measures used (overnight travel, having a secondary residence, travel outside of district, etc).

ETHICS AND DISSEMINATION

This study consists of reviewing and abstracting existing data from publicly available materials, and therefore does not require ethical approval. The results of this study will be submitted for peer reviewed publication and may be presented at a relevant global health conference.

The role of religious leaders on the use of HIV/AIDS prevention strategies among young people (15-24) in Lira district, Uganda

BACKGROUND

Young people (15-24 years) bear the highest burden of new infections and are particularly vulnerable because of their highly risky behavior such as early sexual activity. There is paucity of information on the role of religious leaders in the multi-sectoral fight against HIV/AIDS. We examined the role of religious leaders in the use of HIV prevention strategies among young people.

METHODS

A cross sectional study was conducted between March and April 2021 among 422 randomly selected young people in Lira district, Uganda. An interviewer administered a questionnaire to the young people in order to collect quantitative data. A total 20 key informants were purposively sampled and interviews were conducted with religious leaders using a key informant's interview guide. Data was collected on social demographics, HIV prevention messages, and awareness about HIV prevention strategies. Data was analyzed using Stata version 15 using proportions, means, percentages, frequencies, and logistic regression analysis at a 95% level of significance. Qualitative data was analyzed using thematic content analysis and the major themes were generated from the participants' responses.

RESULTS

About 57.1% (241/422) of the respondents were females. The prevalence of use of HIV prevention strategies among young people was 69.4%. Factors significantly associated with the use of HIV prevention included completing the primary level (aOR 4.95, p< 0.05), completing at least A level (aOR 8.85, p < <0.05), Awareness of HIV prevention strategies advocated for by religious leaders (aOR 0.02, p<0.001), religious leaders provided targeted HIV prevention messages (aOR 2.53, p<0.01), Advocacy for abstinence outside marriage and fidelity in marriage (aOR 35.6, p<0.01), Religious leaders preaching about HIV prevention (aOR 4.88, p<0.001). Qualitative data indicated that a section of religious leaders recommended abstinence/faithfulness. Condom use was the most discouraged HIV prevention strategy. However, most religious leaders agree with the fact that they have a role to play in HIV prevention, which includes sensitization, teaching and organizing sermons about HIV prevention.

CONCLUSION

The use of HIV prevention strategies advocated for by religious leaders among young people was nearly 70%. This finding indicates that religious leaders have a role to play in HIV/AIDS prevention among young people in the Lira district. This calls for the involvement of religious leaders in HIV prevention programs tailored to prevent new infections of HIV among young people.

The Impact of Genital Ulcers on HIV Transmission Has Been Underestimated—A Critical Review

In the early 1990s, several observational studies determined that genital ulcer disease (GUD), in either the index or the exposed person, facilitates HIV transmission. Several meta-analyses have since presented associated risk ratios (RR) over the baseline per-act transmission probability (PATP) usually in the range of 2–5. Here we review all relevant observational studies and meta-analyses, and show that the estimation of RRs was, in most cases, biased by assuming the presence of GUD at any time during long follow-up periods, while active genital ulcers were present in a small proportion of the time. Only two studies measured the GUD co-factor effect in PATPs focusing on acts in which ulcers were present, and both found much higher RRs (in the range 11–112). We demonstrate that these high RRs can be reconciled with the studies on which currently accepted low RRs were based, if the calculations are restricted to the actual GUD episodes. Our results indicate that the effect of genital ulcers on the PATP of HIV might be much greater than currently accepted. We conclude that the medical community should work on the assumption that HIV risk is very high during active genital ulcers.

The Role of Phylogenetics in Discerning HIV-1 Mixing among Vulnerable Populations and Geographic Regions in Sub-Saharan Africa: A Systematic Review

To reduce global HIV-1 incidence, there is a need to understand and disentangle HIV-1 transmission dynamics and to determine the geographic areas and populations that act as hubs or drivers of HIV-1 spread. In Sub-Saharan Africa (sSA), the region with the highest HIV-1 burden, information about such transmission dynamics is sparse. Phylogenetic inference is a powerful method for the study of HIV-1 transmission networks and source attribution. In this review, we assessed available phylogenetic data on mixing between HIV-1 hotspots (geographic areas and populations with high HIV-1 incidence and prevalence) and areas or populations with lower HIV-1 burden in sSA. We searched PubMed and identified and reviewed 64 studies on HIV-1 transmission dynamics within and between risk groups and geographic locations in sSA (published 1995-2021). We describe HIV-1 transmission from both a geographic and a risk group perspective in sSA. Finally, we discuss the challenges facing phylogenetic inference in mixed epidemics in sSA and offer our perspectives and potential solutions to the identified challenges.

Characterization of geographic mobility among participants in facility- and community-based tuberculosis case finding in urban Uganda

Background

International and internal migration are recognized risk factors for tuberculosis (TB). Geographic mobility, including travel for work, education, or personal reasons, may also play a role in TB transmission, but this relationship is poorly defined. We aimed to define geographic mobility among participants in facility- and community-based TB case finding in Kampala, Uganda, and to assess associations between mobility, access to care, and TB disease.

Methods

We included consecutive individuals age ≥15 years diagnosed with TB disease through either routine health facility practices or community-based case finding (consisting of door-to-door testing, venue-based screening, and contact investigation). Each case was matched with one (for community-based enrollment) or two (health facility enrollment) TB-negative controls. We conducted a latent class analysis (LCA) of eight self-reported characteristics to identify and define mobility; we selected the best-fit model using Bayesian Information Criterion. We assessed associations between mobility and TB case status using multivariable conditional logistic regression.

Results

We enrolled 267 cases and 432 controls. Cases were more likely than controls to have been born in Kampala (p<0.001); there was no difference between cases and controls for remaining mobility characteristics. We selected a two-class LCA model; the “mobile” class was perfectly correlated with a single variable: travel (>3 km) from residence ≥2 times per month. Mobility was associated with a 28% reduction in odds of being a TB case (adjusted matched odds ratio 0.72 [95% confidence interval 0.49, 1.06]).

Conclusion

Frequency of out-of-neighborhood travel is an easily measured variable that correlates closely with predicted mobility class membership. Mobility was associated with decreased risk of TB disease; this may be in part due to the higher socioeconomic status of mobile individuals in this population. However, more research is needed to improve assessment of mobility and understand how mobility affects disease risk and transmission.

Costing analysis of an SMS-based intervention to promote HIV self-testing amongst truckers and sex workers in Kenya

Objective

HIV testing rates in many sub-Saharan African countries have remained suboptimal, and there is an urgent need to explore strategic yet cost-effective approaches to increase the uptake of HIV testing, especially among high-risk populations.

Methods

A costing analysis was conducted for a randomized controlled trial (RCT) with male truckers and female sex workers (FSWs) registered in the electronic health record system (EHRS) of the North Star Alliance, which offers healthcare services at major transit hubs in Southern and East Africa. The RCT selected a sample of truckers and FSWs who were irregular HIV testers, according to the EHRS, and evaluated the effect of SMSs promoting the availability of HIV self-testing (HIVST) kits in Kenyan clinics (intervention program) versus a general SMS reminding clients to test for HIV (enhanced and standard program) on HIV testing rates. In this paper, we calculated costs from a provider perspective using a mixed-methods approach to identify, measure, and value the resources utilized within the intervention and standard programs. The results of the analysis reflect the cost per client tested.

Results

The cost of offering HIVST was calculated to be double that of routine facility-based testing (USD 10.13 versus USD 5.01 per client tested), primarily due to the high price of the self-test kit. In the two study arms that only offered provider-administered HIV testing in the clinic, only 1% of truckers and 6% of FSWs tested during the study period, while in the intervention arm, which also offered HST, approximately 4% of truckers and 11% of FSWs tested. These lower than expected outcomes resulted in relatively high cost per client estimates for all three study arms. Within the intervention arm, 65% of truckers and 72% of FSWs who tested chose the HIVST option. However, within the intervention arm, the cost per additional client tested was lower for FSWs than for truckers, at USD 0.15 per additional client tested versus USD 0.58 per additional client tested, driven primarily by the higher response rates.

Conclusion

Whilst the availability of HIVST increased HIV testing among both truckers and FSWs, the cost of providing HIVST is higher than that of a routine health facility-based test, driven primarily by the price of the HIV self-test kit. Future research needs to identify strategies which increase demand for HIVST, and determine whether these strategies and the subsequent increased demand for HIVST are cost-effective in relation to the conventional facility based testing currently available.

Psychosocial characteristics of primary care-seeking long-distance truck drivers in Kenya and associations with HIV testing

The 90-90-90 strategy from the Joint United Nations Programme on HIV/AIDS (UNAIDS) to end the AIDS epidemic by 2020 includes, as its first goal, to have 90% of all people living with HIV to know their status. Achieving this goal will depend on effectively reaching high risk populations, which include mobile populations such as truck drivers. This study aimed to characterise a sample of 305 truck drivers recruited from 2 roadside wellness clinics in Kenya in terms of anticipated HIV stigma, self-efficacy, fatalism, gender equity, sensation seeking, and self-esteem, and then determine the association of these psychosocial characteristics with HIV testing behaviour. Greater general self-efficacy was associated with higher income and more years working as a truck driver. Greater fatalism was associated with non-Christian religion, being married, and having a lower income. Greater gender equity was associated with completing high school, being married, and having higher income. Greater sensation seeking was associated with lower income and fewer years employed as a truck driver. In multivariable logistic regression adjusted for demographic variables, anticipated HIV stigma was negatively associated with having ever tested for HIV (adjusted odds ratio [aOR] = 0.79; 95% confidence interval [CI] = 0.63–0.98; p = 0.034) and self-esteem was positively associated with testing (aOR = 1.06; 95% CI = 1.00–1.12; p = 0.038). Associations with HIV testing behaviour were not significant for self-efficacy, fatalism, gender equity, or sensation seeking. Public health interventions aiming to reduce anticipated stigma and increase self-esteem may potentially increase the uptake of HIV testing among truck drivers. Further research is needed to better understand the influence of these psychosocial characteristics on HIV testing.

Uptake of health services among truck drivers in South Africa: analysis of routine data from nine roadside wellness centres

BACKGROUND

Long-distance truck drivers are occupationally susceptible to poor health outcomes. Their patterns of healthcare utilisation and the suitability of healthcare services available to them are not well documented. We report on truck driver healthcare utilisation across South Africa and characterise the client population of the clinics serving them for future service development.

METHODS

We analysed anonymised data routinely collected over a two-year period at nine Roadside Wellness Centres. Associations between services accessed and socio-demographic characteristics were assessed using univariable and multivariable logistic regression models.

RESULTS

We recorded 16,688 visits by 13,252 individual truck drivers (average of 1.26 visits/person) who accessed 17,885 services for an average of 1.07 services/visit and 1.35 services/person. The mean age of truck drivers was 39 years. Sixty-seven percent reported being in stable relationships. The most accessed services were primary healthcare (PHC)(62%) followed by HIV (32%). Low proportions (≤6%) accessed STI,TB and malaria services. Most visits were characterised by only one service being accessed (93%, n = 15,523/16,688). Of the remaining 7% of visits, up to five services were accessed per visit and the combination of TB /HIV services in one visit remained extremely low (<1%, n = 14/16,688). Besides PHC services at the beginning of the reporting period, all service categories displayed similar seasonal utilisation trends(i.e. service utilisation peaked in the immediate few months post clinics opening and substantially decreased before holidays). Across all service categories, younger truck drivers, those with a stable partner currently, and those of South African origin were the main clinic attendees. Older truck drivers (≥40 years) were more likely to access TB and PHC services, yet less likely to access HIV and STI services. Those with stable partners were less likely to access STI and TB services but more likely to access malaria and PHC services. South African attendees were more likely to access PHC, while attendees from other nationalities were more likely to access HIV and malaria services.

CONCLUSIONS

This utilisation analysis shows that tailored services assist in alleviating healthcare access challenges faced by truck drivers, but it underscores the importance of ensuring that service packages and clinics speak to truck drivers' needs in terms of services offered and clinic location.

HIV testing preferences among long distance truck drivers in Kenya: a discrete choice experiment

Providing HIV testing services to truck drivers in Africa is crucial but has proven challenging. The introduction of HIV self-testing promises to provide expanded service delivery options for clients, potentially increasing demand for services and expanding coverage – especially important for high-risk and difficult-to-reach populations. This study examines the preferences regarding HIV testing service delivery models, among long distance truck drivers to identify testing services that would appeal to this population. Using a discrete choice experiment, this study examines the drivers of choice regarding HIV counselling and testing among 305 truck drivers recruited from two roadside wellness clinics along major trucking routes in Kenya. Participants made trade-offs between characteristics of HIV testing service delivery models by making hypothetical choices in a series of paired HIV testing scenarios. Conditional logit models were used to identify the HIV testing characteristics driving the selection of preferred scenarios, as well as determine whether preferences interact with individual characteristics – especially HIV testing history. Participants preferred free, provider-administered HIV testing at a roadside clinic, using a finger-prick test, with in-person counselling, undertaken in the shortest possible time. The strongest driver of choice was the cost of the test. Those who had never tested previously preferred oral testing and telephonic counselling, while those who were not regular testers favoured clinic based – over self-testing. The results of this study indicate that for the majority of participants – most of whom had tested before – the existing services offered at roadside clinics were the preferred service delivery model. The introduction of oral self-testing increases the options available to truck drivers and may even improve testing uptake for some, especially among those who have never tested before. However, these findings suggest the impact on HIV testing uptake of introducing oral self-testing may be limited in this population.

Effect of HSV-2 infection on subsequent HIV acquisition: an updated systematic review and meta-analysis

Background

HIV and herpes simplex virus type 2 (HSV-2) infections cause a substantial global disease burden and are epidemiologically correlated. Two previous systematic reviews of the association between HSV-2 and HIV found evidence that HSV-2 infection increases the risk of HIV acquisition, but these reviews are now more than a decade old.

Methods

For this systematic review and meta-analysis, we searched PubMed, MEDLINE, and Embase (from Jan 1, 2003, to May 25, 2017) to identify studies investigating the risk of HIV acquisition after exposure to HSV-2 infection, either at baseline (prevalent HSV-2 infection) or during follow-up (incident HSV-2 infection). Studies were included if they were a cohort study, controlled trial, or case-control study (including case-control studies nested within a cohort study or clinical trial); if they assessed the effect of pre-existing HSV-2 infection on HIV acquisition; and if they determined the HSV-2 infection status of study participants with a type-specific assay. We calculated pooled random-effect estimates of the association between prevalent or incident HSV-2 infection and HIV seroconversion. We also extended previous investigations through detailed meta-regression and subgroup analyses. In particular, we investigated the effect of sex and risk group (general population vs higher-risk populations) on the relative risk (RR) of HIV acquisition after prevalent or incident HSV-2 infection. Higher-risk populations included female sex workers and their clients, men who have sex with men, serodiscordant couples, and attendees of sexually transmitted infection clinics.

Findings

We identified 57 longitudinal studies exploring the association between HSV-2 and HIV. HIV acquisition was almost tripled in the presence of prevalent HSV-2 infection among general populations (adjusted RR 2·7, 95% CI 2·2–3·4; number of estimates [N_e]=22) and was roughly doubled among higher-risk populations (1·7, 1·4–2·1; N_e=25). Incident HSV-2 infection in general populations was associated with the highest risk of acquisition of HIV (4·7, 2·2–10·1; N_e=6). Adjustment for confounders at the study level was often incomplete but did not significantly affect the results. We found moderate heterogeneity across study estimates, which was explained by risk group, world region, and HSV-2 exposure type (prevalent vs incident).

Interpretation

We found evidence that HSV-2 infection increases the risk of HIV acquisition. This finding has important implications for management of individuals diagnosed with HSV-2 infection, particularly for those who are newly infected. Interventions targeting HSV-2, such as new HSV vaccines, have the potential for additional benefit against HIV, which could be particularly powerful in regions with a high incidence of co-infection.

Funding

World Health Organization.

Offering self-administered oral HIV testing to truck drivers in Kenya to increase testing: a randomized controlled trial

We conducted a randomized controlled trial among 305 truck drivers from two North Star Alliance roadside wellness clinics in Kenya to see if offering HIV testing choices would increase HIV testing uptake. Participants were randomized to be offered (1) a provider-administered rapid blood (finger-prick) HIV test (i.e., standard of care [SOC]) or (2) a Choice between SOC or a self-administered oral rapid HIV test with provider supervision in the clinic. Participants in the Choice arm who refused HIV testing in the clinic were offered a test kit for home use with phone-based posttest counseling. We compared HIV test uptake using the Mantel Haenszel odds ratio (OR) adjusting for clinic.

Those in the Choice arm had higher odds of HIV test uptake than those in the SOC arm (OR = 1.5), but the difference was not statistically significant (p = 0.189). When adding the option to take an HIV test kit for home use, the Choice arm had significantly greater odds of testing uptake (OR = 2.8, p = 0.002). Of those in the Choice arm who tested, 26.9% selected the SOC test, 64.6% chose supervised self-testing in the clinic, and 8.5% took a test kit for home use.

Participants varied in the HIV test they selected when given choices. Importantly, when participants who refused HIV testing in the clinic were offered a test kit for home use, an additional 8.5% tested. Offering truck drivers a variety of HIV testing choices may increase HIV testing uptake in this key population.

A qualitative study of migrant-related stressors, psychosocial outcomes and HIV risk behaviour among truck drivers in Zambia

Truck drivers are part of mobile populations which have been noted as a key population at risk of HIV in Zambia. This study was aimed at: (1) determining potentially traumatic events (PTEs), labour migrant-related stressors, psychosocial problems and HIV risk behaviours among truck drivers in Zambia; and (2) examining the relationship between PTEs, migrant-related stressors, psychosocial outcomes and HIV sexual risk behaviour among truck drivers in Zambia. We conducted 15 semi-structured interviews with purposively sampled male truck drivers at trucking companies in Lusaka, Zambia. Findings indicate that truck drivers experience multiple stressors and potentially traumatic incidences, including delays and long waiting hours at borders, exposure to crime and violence, poverty, stress related to resisting temptation of sexual interactions with sex workers or migrant women, and job-related safety concerns. Multiple psychosocial problems such as intimate partner violence, loneliness, anxiety and depression-like symptoms were noted. Transactional sex, coupled with inconsistent condom use, were identified as HIV sexual risk behaviours. Findings suggest the critical need to develop HIV-prevention interventions which account for mobility, potentially traumatic events, psychosocial problems, and the extreme fear of HIV testing among this key population.

Principles of Infectious Diseases: Transmission, Diagnosis, Prevention, and Control

Infectious disease control and prevention relies on a thorough understanding of the factors determining transmission. This article summarizes the fundamental principles of infectious disease transmission while highlighting many of the agent, host, and environmental determinants of these diseases that are of particular import to public health professionals. Basic principles of infectious disease diagnosis, control, and prevention are also reviewed.

Healthcare Programmes for Truck Drivers in Sub-Saharan Africa: A Systematic Review and Meta-Analysis

BACKGROUND

Truck drivers have unique health needs, and by virtue of their continuous travel, experience difficulty in accessing healthcare. Currently, planning for effective care is hindered by lack of knowledge about their health needs and about the impact of on-going programmes on this population's health outcomes. We reviewed healthcare programmes implemented for sub-Saharan African truck drivers, assessed the evaluation methods, and examined impact on health outcomes.

METHODS

We searched scientific and institutional databases, and online search engines to include all publications describing a healthcare programme in sub-Saharan Africa where the main clients were truck drivers. We consulted experts and organisations working with mobile populations to identify unpublished reports. Forest plots of impact and outcome indicators with unadjusted risk ratios and 95% confidence intervals were created to map the impact of these programmes. We performed a subgroup analysis by type of indicator using a random-effects model to assess between-study heterogeneity. We conducted a sensitivity analysis to examine both the summary effect estimate chosen (risk difference vs. risk ratio) and model to summarise results (fixed vs. random effects).

RESULTS

Thirty-seven publications describing 22 healthcare programmes across 30 countries were included from 5,599 unique records. All programmes had an HIV-prevention focus with only three expanding their services to cover conditions other primary healthcare services. Twelve programmes were evaluated and most evaluations assessed changes in input, output, and outcome indicators. Absence of comparison groups, preventing attribution of the effect observed to the programme and lack of biologically confirmed outcomes were the main limitations. Four programmes estimated a quantitative change in HIV prevalence or reported STI incidence, with mixed results, and one provided anecdotal evidence of changes in AIDS-related mortality and social norms. Most programmes showed positive changes in risk behaviours, knowledge, and attitudes. Our conclusions were robust in sensitivity analyses.

CONCLUSION

Diverse healthcare programmes tailored to the needs of truck drivers implemented in 30 sub-Saharan African countries have shown potential benefits. However, information gaps about availability of services and their effects impede further planning and implementation of effective healthcare programmes for truck drivers.

On the road again: concurrency and condom use among Uganda truck drivers

Long-distance truck drivers have been shown to be a critical population in the spread of HIV in Africa. In 2009, surveys with 385 Ugandan long-distance truck drivers measured concurrency point prevalence with two methods; it ranged from 37.4% (calendar-method) to 50.1% (direct question). The majority (84%) of relationships reported were long-term resulting in a long duration of overlap (average of 58 months) across concurrent partnerships. Only 7% of these men reported using any condoms with their spouses during the past month. Among all non-spousal relationships, duration of relationship was the factor most strongly associated with engaging in unprotected sex in the past month in a multivariable analyses controlling for partner and relationship characteristics. Innovative intervention programs for these men and their partners are needed that address the realities of truck drivers' lifestyles.

The influence of religion on sexual HIV risk

This systematic review examines the relationship between religion and sexual HIV risk behavior. It focuses primarily on how studies have conceptualized and defined religion, methodologies, and sexual risk outcomes. We also describe regions where studies were conducted and mechanisms by which religion may be associated with sexual risk. We included 137 studies in this review, classifying them as measuring: (1) only religious affiliation (n = 57), (2) only religiosity (n = 48), and (3) both religious affiliation and religiosity (n = 32). A number of studies identified lower levels of sexual HIV risk among Muslims, although many of these examined HIV prevalence rather than specific behavioral risk outcomes. Most studies identified increased religiosity to be associated with lower levels of sexual HIV risk. This finding persists but is weaker when the outcome considered is condom use. The paper reviews ways in which religion may contribute to increase and reduction in sexual HIV risk, gaps in research, and implications for future research on religion and HIV.

Sexually transmitted infections and male circumcision: a systematic review and meta-analysis

The claim that circumcision reduces the risk of sexually transmitted infections has been repeated so frequently that many believe it is true. A systematic review and meta-analyses were performed on studies of genital discharge syndrome versus genital ulcerative disease, genital discharge syndrome, nonspecific urethritis, gonorrhea, chlamydia, genital ulcerative disease, chancroid, syphilis, herpes simplex virus, human papillomavirus, and contracting a sexually transmitted infection of any type. Chlamydia, gonorrhea, genital herpes, and human papillomavirus are not significantly impacted by circumcision. Syphilis showed mixed results with studies of prevalence suggesting intact men were at great risk and studies of incidence suggesting the opposite. Intact men appear to be of greater risk for genital ulcerative disease while at lower risk for genital discharge syndrome, nonspecific urethritis, genital warts, and the overall risk of any sexually transmitted infection. In studies of general populations, there is no clear or consistent positive impact of circumcision on the risk of individual sexually transmitted infections. Consequently, the prevention of sexually transmitted infections cannot rationally be interpreted as a benefit of circumcision, and any policy of circumcision for the general population to prevent sexually transmitted infections is not supported by the evidence in the medical literature.

Sexual risk behaviours, condom use and sexually transmitted infection treatment-seeking behaviours among female sex workers and truck drivers in Uganda

We assessed sexual risk behaviours, condom use and sexually transmitted infection (STI) treatment-seeking behaviours among truckers and female sex workers (FSWs) operating at 12 hotspots along two major transport corridors in Uganda. Participants were identified through local contact persons: 261 truckers and 259 FSWs were interviewed. FSWs reported a mean number of 28 partners in the past 30 days while truckers reported a mean of seven partners. Ninety-four percent of FSWs and 87% of truckers reported condom use in the past month; however, only 21% of truckers and 45% of FSWs reported using condoms consistently during that time. More than half of truckers (n = 261) and 77% of FSWs (n = 259) reported that they suffered from STIs in the past year, and 93% of FSWs and 92.9% of truckers sought treatment for STIs in the past year. Of these, 78% of truckers and 86% of FSWs sought treatment at least three days following recognition of symptoms. These findings suggest that FSWs and truckers engage in high-risk sexual behaviours characterized by multiple sexual partnerships, low consistent condom use and delayed treatment-seeking behaviours.

Mobility and HIV in Central America and Mexico: a critical review

Mobility is a key determinant of HIV/sexually transmitted infection (STI) transmission dynamics in Asia and Africa. Scant data exist regarding its dynamic impacts on HIV/STI risk in Central America and Mexico. Our objective was to critically review the epidemiology and social and structural context of HIV/STI risk among mobile populations in Central America and Mexico. Eligible articles were published in English or Spanish between January 1, 2000 and August 31, 2010; conducted in Central America or Mexico; specified the mobile population included; and described primary research. 2045 records were screened, 275 articles reviewed, and 22 studies included. Mobility is associated with increased HIV risk behaviors, though it also may increase preventive behaviors. Among mobile groups in Central America and Mexico, social isolation, the socio-economic impacts of displacement, gender inequalities, and stigma/discrimination shape HIV risk. Epidemiologic research and multi-level interventions that target and engage vulnerable groups in transit stations are recommended.

The association between religious affiliation and frequency of attendance at religious services on HIV risky behaviors among people living with HIV/AIDS

The purpose of this study was to examine if religious affiliation and frequency of attendance at religious services were associated with HIV risky behaviors among people living with HIV/AIDS (PLWHA). The participants are HIV positive clients of a community based HIV/AIDS outreach facility (CBHAOF) located in Montgomery, Alabama, USA. The participants completed the questionnaire during their medical visits to the clinic at their own convenience and that of the facility's staff. A total of 341 questionnaires were distributed to PLWHA and 326 (96%) were fully completed and returned. There were more male than female participants (56 versus 42%). The majority of the respondents (67%) were between 30 and 49 years of age. Nearly two thirds of the participants (64%) were African Americans whilst 36% were other races combined (White = 29%, Hispanic = 3% and other races = 4%). A chi-square test was used to examine the association between selected variables. Findings show substantial variations of selected HIV risky behaviors according to religious affiliation and frequency of attendance at religious services (p < 0.05). The study findings suggest the importance of religious affiliation and frequency of attendance at religious services in reducing HIV risky behaviors among PLWHA. The findings have implications for HIV/AIDS prevention and we recommend that it is important to incorporate Faith-based organizations in the global fight against HIV/AIDS.

HIV-malaria co-infection: effects of malaria on the prevalence of HIV in East sub-Saharan Africa

OBJECTIVE

To examine the association between malaria and HIV prevalence in East sub-Saharan Africa.

METHODS

Using large nationally representative samples of 19,735 sexually active adults from the 2003-04 HIV/AIDS indicator surveys conducted in Kenya, Malawi and Tanzania, and the atlas malaria project, we analysed the relationship between malaria and HIV prevalence adjusting for important socioeconomic and biological cofactors.

RESULTS

In adjusted models, individuals who live in areas with high Plasmodium falciparum parasite rate (PfPR > 0.42) had increased estimated odds of being HIV positive than individuals who live in areas with low P. falciparum parasite rate (PfPR ≤ 0.10) [men: estimated odds ratio (OR) 2.24, 95% confidence interval (CI) 1.62-3.12; women: estimated OR 2.44, 95% CI 1.85-3.21].

CONCLUSION

This is the first study to report malaria as a risk factor of concurrent HIV infection at the population level. According to our results, individuals who live in areas with high P. falciparum parasite rate have about twice the risk of being HIV positive compared with individuals who live in areas with low P. falciparum parasite rate. Our work emphasizes the need for field studies focused on quantifying the interaction among parasitic infections and risk of HIV infection, and studies to explore the impact of control interventions. Programmes focused on reducing malaria transmission will be important to address, especially in HIV-infected individuals.

HIV/AIDS and the long-distance truck drivers in south-west Nigeria: a cross-sectional survey on the knowledge, attitude, risk behaviour and beliefs of truckers

OBJECTIVES

According to the last HIV surveillance survey conducted in 2008, the overall National HIV prevalence in Nigeria stands at 4.6%. Recent studies and estimates by UNAIDS/WHO show higher prevalences in some selected states in Nigeria. The focus of this study is to determine the prevalence, risk behaviour, attitude and knowledge of HIV among long-distance heavy-truckers from a cross-sectional survey conducted in the south-west Nigeria.

METHODS

Four major truck terminals (devoted to long-distance trips) in south western Nigeria were identified. A cross-sectional survey was conducted using a total sample size of 451 truckers who consented to be interviewed. A questionnaire (in English, Hausa and Yoruba languages) for data collection on the socio-demographic, risk behaviour, attitude and knowledge of HIV from the truckers was also designed. The multiple logistic regressions analysis was used to assess the association between some selected variables and factors.

RESULTS

Only 164 (36.4%) participants out of the study population of 451 were tested for HIV (due to limited test facilities and consent) and the prevalence of HIV antibodies among the truckers was found to be 2.4% (4/164) with all the infected individuals being within 21-30 years of age. 309 (68.1%) of the respondents admitted that they were at risk of contracting HIV while a total of 249 (55.3%) admitted that they had more than one sexual partners. In addition, while 392 (86.9%) said it was important for them to know their HIV status, 88 (19.5%) said that they would commit suicide should they test positive for HIV.

CONCLUSION

Although the HIV prevalence rate observed among the tested participants (2.4%) was lower than the overall national prevalence (4.6%), the result calls for concern as it showed that the population of truckers is a potential high risk group in Nigeria. Also, the mobile nature of this high-risk group has made getting HIV/AIDS awareness messages across to them a difficult task.

Population level impact of an imperfect prophylactic vaccine for herpes simplex virus-2

BACKGROUND

The continuation of developing Herpes simplex virus type-2 (HSV-2) prophylactic vaccines requires parallel mathematical modeling to quantify the effect on the population of these vaccines.

METHODS

Using mathematical modeling we derived 3 summary measures for the population effect of imperfect HSV-2 vaccines as a function of their efficacies in reducing susceptibility (VES), genital shedding (VEP), and infectivity during shedding (VEI). In addition, we studied the population level effect of vaccine intervention using representative vaccine efficacies.

RESULTS

A vaccine with limited efficacy of reducing shedding frequency (VEP = 10%) and infectivity (VEI = 0%) would need to reduce susceptibility by 75% (VES = 75%) to substantially reduce the sustainability of HSV-2 infection in a population. No reduction in susceptibility would be required to reach this target in a vaccine that decreased shedding by 75% (VES = 0%, VEP = 75%, VEI = 0%). Mass vaccination using a vaccine with imperfect efficacies (VES = 30%, VEP = 75%, and VEI = 0%) in Kisumu, Kenya, in 2010 would decrease prevalence and incidence in 2020 by 7% and 30%, respectively. For lower prevalence settings, vaccination is predicted to have a lower effect on prevalence.

CONCLUSION

A vaccine with substantially high efficacy of reducing HSV-2 shedding frequency would have a desirable effect at the population level. The vaccine's short-term impact in a high prevalence setting in Africa would be a substantial decrease in incidence, whereas its immediate impact on prevalence would be small and would increase slowly over time.

Epidemiology of HIV infection in the Middle East and North Africa

OBJECTIVE

The Middle East and North Africa (MENA) region continues to be perceived as a region with very limited HIV epidemiological data, raising many controversies about the status of the epidemic in this part of the world. The objective of this review and synthesis was to address the dearth of strategic interpretable data on HIV in MENA by delineating a data-driven overview of HIV epidemiology in this region.

METHODS

A comprehensive systematic review of HIV, sexually transmitted infections (STIs) and risk behavior studies in MENA, irrespective of design, was undertaken. Sources of data included Medline for peer-reviewed publications, Google Scholar for other scientific literature published in nonindexed local and regional journals, international organizations reports and databases, country-level reports and database including governmental and nongovernmental organizations publications, as well as various other institutional documents.

RESULTS

Over 5000 sources of data related to HIV and STIs were identified and reviewed. The quality of data and nature of study designs varied substantially. There was no evidence for a sustainable HIV epidemic in the general population in any of the MENA countries, except possibly for southern Sudan. The general pattern in different countries in MENA points towards emerging epidemics in high-risk populations including injecting drug users, men who have sex with men (MSM) and to a lesser extent female sex workers, with heterogeneity between countries on the relative role of each of these high-risk groups. Exogenous HIV exposures among nationals linked to travel abroad appeared to be the dominant HIV transmission pattern in a few MENA countries with no evidence for much epidemic or endemic transmission. The role of bridging populations in bridging the HIV infection to the general population was found to be very limited.

CONCLUSION

Although they do not provide complete protection against HIV spread, near universal male circumcision and possibly the prevailing sexually conservative cultural norms seemed to have played so far a protective role in slowing and limiting HIV transmission in MENA relative to other regions. If the existing social and epidemiological context remains largely the same, HIV epidemic transmission is likely to remain confined to high-risk populations and their sexual partners, in addition to exogenous exposures. HIV prevention efforts in this region, which continue to be stymied by stigma associated with HIV/AIDS and related risk behaviors, need to be aggressively expanded with a focus on controlling HIV spread along the contours of risk and vulnerability. There is still a window of opportunity to control further HIV transmission among high-risk groups in MENA that, if missed, may entail a health and socioeconomic burden that the region, in large part, is unprepared for.

Late diagnosis and subsequent survival among HIV-infected truck drivers in the northwest of France: a retrospective study

Late diagnosis of HIV infection is associated with a lower survival rate. Because of several consecutive cases of late diagnosis of AIDS occurring in truck drivers, a retrospective study was carried out in the northwest of France. Truck drivers were significantly associated with a late diagnosis of HIV infection (P = 0.009) and an increased risk of death (P = 0.03). Consequently, prevention and HIV-testing campaigns targeting this profession appear necessary.

Emerging discourse: Islamic teaching in HIV prevention in Kenya

Islamic values portraying sex outside of marriage as sinful are often believed to contribute to HIV transmission as they reject safe-sex practices. Moreover, stigma associated with sinful behaviour is frequently assumed to interfere with access to care for those infected. In contrast, adherence to religious values such as abstinence is viewed as an explanation for the relatively low incidence of HIV infection in Islamic populations. Inspired by this debate, a study was conducted into the possibilities of using Islamic texts as a starting point for health promotion addressing HIV infection and HIV/AIDS-related stigma in Lamu, a Muslim community in Kenya. The study also explored the potential role of Lamu's Islamic leaders in the delivery of that health promotion. In collaboration with Islamic leaders, texts were identified that applied to sexual conduct, health, stigma and the responsibilities of Islamic leaders towards their congregations. In spite of the association of HIV with improper sexual behaviour, Islamic texts offer a starting point for tackling HIV transmission and HIV/AIDS-related stigma. Under particular conditions, the identified Islamic texts may even justify the promotion of safer-sex methods, including condom use.

Religion and HIV in Tanzania: influence of religious beliefs on HIV stigma, disclosure, and treatment attitudes

BACKGROUND

Religion shapes everyday beliefs and activities, but few studies have examined its associations with attitudes about HIV. This exploratory study in Tanzania probed associations between religious beliefs and HIV stigma, disclosure, and attitudes toward antiretroviral (ARV) treatment.

METHODS

A self-administered survey was distributed to a convenience sample of parishioners (n = 438) attending Catholic, Lutheran, and Pentecostal churches in both urban and rural areas. The survey included questions about religious beliefs, opinions about HIV, and knowledge and attitudes about ARVs. Multivariate logistic regression analysis was performed to assess how religion was associated with perceptions about HIV, HIV treatment, and people living with HIV/AIDS.

RESULTS

Results indicate that shame-related HIV stigma is strongly associated with religious beliefs such as the belief that HIV is a punishment from God (p < 0.01) or that people living with HIV/AIDS (PLWHA) have not followed the Word of God (p < 0.001). Most participants (84.2%) said that they would disclose their HIV status to their pastor or congregation if they became infected. Although the majority of respondents (80.8%) believed that prayer could cure HIV, almost all (93.7%) said that they would begin ARV treatment if they became HIV-infected. The multivariate analysis found that respondents' hypothetical willingness to begin ARV treatme was not significantly associated with the belief that prayer could cure HIV or with other religious factors. Refusal of ARV treatment was instead correlated with lack of secondary schooling and lack of knowledge about ARVs.

CONCLUSION

The decision to start ARVs hinged primarily on education-level and knowledge about ARVs rather than on religious factors. Research results highlight the influence of religious beliefs on HIV-related stigma and willingness to disclose, and should help to inform HIV-education outreach for religious groups.

Quantitating the multiplicity of infection with human immunodeficiency virus type 1 subtype C reveals a non-poisson distribution of transmitted variants

Identifying the specific genetic characteristics of successfully transmitted variants may prove central to the development of effective vaccine and microbicide interventions. Although human immunodeficiency virus transmission is associated with a population bottleneck, the extent to which different factors influence the diversity of transmitted viruses is unclear. We estimate here the number of transmitted variants in 69 heterosexual men and women with primary subtype C infections. From 1,505 env sequences obtained using a single genome amplification approach we show that 78% of infections involved single variant transmission and 22% involved multiple variant transmissions (median of 3). We found evidence for mutations selected for cytotoxic-T-lymphocyte or antibody escape and a high prevalence of recombination in individuals infected with multiple variants representing another potential escape pathway in these individuals. In a combined analysis of 171 subtype B and C transmission events, we found that infection with more than one variant does not follow a Poisson distribution, indicating that transmission of individual virions cannot be seen as independent events, each occurring with low probability. While most transmissions resulted from a single infectious unit, multiple variant transmissions represent a significant fraction of transmission events, suggesting that there may be important mechanistic differences between these groups that are not yet understood.

Heterosexual risk of HIV-1 infection per sexual act: systematic review and meta-analysis of observational studies

We did a systematic review and meta-analysis of observational studies of the risk of HIV-1 transmission per heterosexual contact. 43 publications comprising 25 different study populations were identified. Pooled female-to-male (0.04% per act [95% CI 0.01-0.14]) and male-to-female (0.08% per act [95% CI 0.06-0.11]) transmission estimates in high-income countries indicated a low risk of infection in the absence of antiretrovirals. Low-income country female-to-male (0.38% per act [95% CI 0.13-1.10]) and male-to-female (0.30% per act [95% CI 0.14-0.63]) estimates in the absence of commercial sex exposure (CSE) were higher. In meta-regression analysis, the infectivity across estimates in the absence of CSE was significantly associated with sex, setting, the interaction between setting and sex, and antenatal HIV prevalence. The pooled receptive anal intercourse estimate was much higher (1.7% per act [95% CI 0.3-8.9]). Estimates for the early and late phases of HIV infection were 9.2 (95% CI 4.5-18.8) and 7.3 (95% CI 4.5-11.9) times larger, respectively, than for the asymptomatic phase. After adjusting for CSE, presence or history of genital ulcers in either couple member increased per-act infectivity 5.3 (95% CI 1.4-19.5) times versus no sexually transmitted infection. Study estimates among non-circumcised men were at least twice those among circumcised men. Low-income country estimates were more heterogeneous than high-income country estimates, which indicates poorer study quality, greater heterogeneity of risk factors, or under-reporting of high-risk behaviour. Efforts are needed to better understand these differences and to quantify infectivity in low-income countries.

Separation of spouses due to travel and living apart raises HIV risk in Tanzanian couples

BACKGROUND

Persons with absent partners may be more vulnerable to risky sexual behavior and therefore HIV. Partner absence can be due to traveling (e.g., family visits or funerals) or to living apart (e.g., work-related or in polygamous marriages). We investigated to what extent partner absence leads to more risky sexual behavior in Tanzanian couples.

METHODS

We compared 95 men and 85 women living apart with 283 men and 331 women living together. Only persons who were still married were included, either living apart or cohabiting at the time of the interview. Subjects were classified into 4 groups: coresidents being either nonmobile or mobile, and people living apart either frequently or infrequently seeing each other.

RESULTS

Most people living apart were polygamously married. Men living apart did not report more extramarital sex than coresident men. However, among coresident men, extramarital sex was reported by 35% of those being mobile compared with 15% of those nonmobile. Among women, those living apart reported extramarital sex more often than coresidents (14% vs. 7%), and this was mainly due to women living apart who infrequently saw their husbands.

CONCLUSIONS

Risky sexual behavior occurs more often in mobile coresident men, and in women living apart infrequently seeing their spouses. These groups are relatively easy to identify and need extra attention in HIV prevention campaigns.

A nested case-control study of sexual practices and risk factors for prevalent HIV-1 infection among young men in Kisumu, Kenya

OBJECTIVES

To investigate sexual practices and risk factors for prevalent HIV infection among young men in Kisumu, Kenya.

GOAL

The goal of this study was to identify behaviors associated with HIV in Kisumu to maximize the effectiveness of future prevention programs.

STUDY DESIGN

Lifetime sexual histories were collected from a nested sample of 1337 uncircumcised participants within the context of a randomized controlled trial of male circumcision to reduce HIV incidence.

RESULTS

Sixty-five men (5%) tested positive for HIV. Multiple logistic regression revealed the following independent predictors of HIV: older age, less education, being married, being Catholic, >4 lifetime sex partners, prior treatment for an STI, sex during partner's menstruation, ever practicing bloodletting, and receipt of a medical injection in the last 6 months. Prior HIV testing and postcoital cleansing were protective.

CONCLUSIONS

This analysis confirms the importance of established risk factors for HIV and identifies practices that warrant further investigation.

Mobility and its liminal context: Exploring sexual partnering among truck drivers crossing the Southern Brazilian border

Mobile populations, including truck drivers, are at elevated risk of acquiring HIV and other sexually transmitted infections (STI). However, measures of mobility have been poorly operationalized and little research exists exploring the psychosocial context of mobility and sexual risk taking. A systematic sample of 1775 male truck drivers underwent interview at two customs stations on the Southern Brazilian international border in 2003. The psychosocial effect of being mobile was assessed by clustering truckers based on perceptions of the liminal environment, or being outside of one's normal social environment. The relationship between physical mobility (nights spent at home) and liminal cluster with sexual partnerships was assessed. The clustering procedure yielded three dispositions towards the liminal environment. Compared to truckers in the baseline cluster, those who perceive the environment as (1) very, or (2) moderately permissive had increased odds of reporting a commercial sex partner in the past six months and reported increased numbers of commercial partners. For each week slept at home, the odds of reporting a commercial partner decreased by a factor of 0.73 and the average number of commercial partners decreased by a rate of 0.76. Physical and psychosocial measures of mobility were associated independently with increased partnering on the road. Additional exploration of how the liminal environment shapes mobile populations' sexual decision making and vulnerability to STI is warranted.

Assessment of condom use among Bolivian truck drivers through the lens of social cognitive theory

This study demonstrates that Bolivian long distance truck drivers are a high risk population of HIV infection and transmission, supporting other global studies involving truck drivers and their high risk. The aims of this investigation were to estimate the prevalence of high risk behaviors and to identify predictors of condom use in this population. Analysis was completed on survey results from 246 male truckers (aged 18-67). About one in three of the truck drivers (30%) reported having had a sexually transmitted infection sometime in their past. More than half (56%) reported having sex with casual partners. Other risks involved unprotected anal sex. Age and two social cognitive constructs (outcome expectations and perceived social norms) predicted condom use from logistic regression analysis. The authors discuss the need for expanded HIV/sexually transmitted infection prevention programs that incorporate social cognitions.

STD treatment: how can it improve HIV prevention in the South?

BACKGROUND

Rates of human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS) and sexually transmitted diseases (STDs) are disproportionately high in the Southern United States. A high percentage of the population is black, and STD/HIV rates are particularly high among this group. Control and treatment of STDs offers promise as an HIV prevention strategy, and nowhere more than in the South.

OBJECTIVE

Identify those specific recommendations for control and treatment of STDs that available evidence indicates can reduce HIV transmission.

STUDY

Review of published literature.

RESULTS

Community trials produced inconsistent results but still suggest that STD treatment can reduce HIV transmission in the United States. Treatment of symptomatic STDs among those with HIV-infection should reduce HIV infectivity. There is as yet only limited evidence that STD treatment can reduce HIV susceptibility, although promising studies addressing herpes simplex virus are under way.

CONCLUSIONS

The unacceptably large racial disparities in STD rates must be addressed, symptomatic STDs among HIV-infected individuals treated, and syphilis prevention activities continued. Detection of unrecognized HIV infections among those seeking STD services should be a priority; identification of those with STDs and acute HIV infection may provide unique HIV prevention opportunities.

Risk Factors for HIV Infection in a National Adult Population

OBJECTIVE

To study demographic, social, behavioral, and biological variables as risk factors for HIV infection among men and women in Kenya.

METHODS

Data from the cross-sectional, population-based 2003 Kenya Demographic and Health Survey were used. During the course of survey fieldwork, 3,273 women aged 15 to 49 years and 2,941 men aged 15 to 54 years gave consent to have a few drops of blood taken for anonymous testing. HIV serostatus data for men and women were analyzed for their relationships to key characteristics using bivariate and multivariate techniques to determine factors associated with being HIV-positive.

RESULTS

National HIV prevalence in Kenya was found to be 6.7%. In the analysis of the study sample, uncircumcised men were 4 times more likely to be HIV-positive than those who were not. Compared with nonpolygynously married women, widowed women (odds ratio [OR] = 10.9), divorced women (OR = 2.3), and women who were 1 of 3 or more wives (OR = 3.4) were all at higher risk for being HIV-positive. Both men and women from Nyanza province were at a significantly higher risk for infection with HIV (OR = 2.9 and 2.3, respectively) than were the men and women from Nairobi. Men aged 35 to 44 years had the highest risk of being HIV-positive, whereas the ages of highest risk for women were 25 to 29 years. Increased wealth was positively related to risk for HIV: the wealthiest women were 2.6 times more likely than the poorest women to be HIV-positive. A key finding was that both men and women who considered themselves to be at low risk for contracting HIV were, in fact, the most likely to be HIV-positive.

CONCLUSIONS

This analysis demonstrates that HIV is a multidimensional epidemic, with demographic, residential, social, biological, and behavioral factors all exerting influence on individual probability of becoming infected with HIV. Although all of these factors contribute to the risk profile for a given individual, the results suggest that differences in biological factors such as circumcision and sexually transmitted infections may be more important in assessing risk for HIV than differences in sexual behavior.

Male circumcision and risk of syphilis, chancroid, and genital herpes: a systematic review and meta-analysis

OBJECTIVES

Male circumcision is associated with reduced risk of HIV infection. This may be partly because of a protective effect of circumcision on other sexually transmitted infections (STI), especially those causing genital ulcers, but evidence for such protection is unclear. Our objective was to conduct a systematic review and meta-analyses of the associations between male circumcision and infection with herpes simplex virus type 2 (HSV-2), Treponema pallidum, or Haemophilus ducreyi.

METHODS

Electronic databases (1950-2004) were searched using keywords and text terms for herpes simplex, syphilis, chancroid, ulcerative sexually transmitted diseases, or their causative agents, in conjunction with terms to identify epidemiological studies. References of key articles were hand searched, and data were extracted using standardised forms. Random effects models were used to summarise relative risk (RR) where appropriate.

RESULTS

26 articles met the inclusion criteria. Most syphilis studies reported a substantially reduced risk among circumcised men (summary RR = 0.67, 95% confidence interval (CI) 0.54 to 0.83), although there was significant between study heterogeneity (p = 0.01). The reduced risk of HSV-2 infection was of borderline statistical significance (summary RR = 0.88, 95% CI 0.77 to 1.01). Circumcised men were at lower risk of chancroid in six of seven studies (individual study RRs: 0.12 to 1.11).

CONCLUSIONS

This first systematic review of male circumcision and ulcerative STI strongly indicates that circumcised men are at lower risk of chancroid and syphilis. There is less association with HSV-2. Potential male circumcision interventions to reduce HIV in high risk populations may provide additional benefit by protecting against other STI.

High rates of syphilis among STI patients are contributing to the spread of HIV-1 in India

BACKGROUND

Recent syphilis outbreaks have raised concern regarding the potential enhancement of HIV transmission. The incidence of syphilis and its association with HIV-1 infection rates among a cohort of sexually transmitted infection (STI) clinic attendees was investigated.

METHODS

2732 HIV-1 seronegative patients attending three STI and one gynaecology clinic, were enrolled from 1993-2000 in an ongoing prospective cohort study of acute HIV-1 infection in Pune, India. At screening and quarterly follow up visits, participants underwent HIV-1 risk reduction counselling, risk behaviour assessment and HIV/STI screening that included testing for serological evidence of syphilis by RPR with TPHA confirmation. Patients with genital ulcers were screened with dark field microscopy.

RESULTS

Among 2324 participants who were HIV-1 and RPR seronegative at baseline, 172 participants were found to have clinical or laboratory evidence of syphilis during follow up (5.4 per 100 person years, 95% CI 4.8 to 6.5 per 100 person years). Independent predictors of syphilis acquisition based on a Cox proportional hazards model included age less than 20 years, lack of formal education, earlier calendar year of follow up, and recent HIV-1 infection. Based on a median follow up time of 11 months, the incidence of HIV-1 was 5.8 per 100 person years (95% CI 5.0 to 6.6 per 100 person years). Using a Cox proportional hazards model to adjust for known HIV risk factors, the adjusted hazard ratio of HIV-1 infection associated with incident syphilis was 4.44 (95% CI 2.96 to 6.65; p<0.001).

CONCLUSIONS

A high incidence rate of syphilis was observed among STI clinic attendees. The elevated risk of HIV-1 infection that was observed among participants with incident syphilis supports the hypothesis that syphilis enhances the sexual transmission of HIV-1 and highlights the importance of early diagnosis and treatment of syphilis.

Herpes simplex virus 2 infection increases HIV acquisition in men and women: systematic review and meta-analysis of longitudinal studies

OBJECTIVE

To estimate the sex-specific effect of herpes simplex virus type 2 (HSV-2) on the acquisition of HIV infection.

BACKGROUND

The increased number of longitudinal studies available since the last meta-analysis was published allows for the calculation of age- and sexual behaviour-adjusted relative risks (RR) separately for men and women.

DESIGN

Systematic review and meta-analysis of longitudinal studies.

METHODS

PubMed, Embase and relevant conference abstracts were systematically searched to identify longitudinal studies in which the relative timing of HSV-2 infection and HIV infection could be established. Where necessary, authors were contacted for separate estimates in men and women, adjusted for age and a measure of sexual behaviour. Summary adjusted RR were calculated using random-effects meta-analyses where appropriate. Studies on recent HSV-2 incidence as a risk factor for HIV acquisition were also collated.

RESULTS

Of 19 eligible studies identified, 18 adjusted for age and at least one measure of sexual behaviour after author contact. Among these, HSV-2 seropositivity was a statistically significant risk factor for HIV acquisition in general population studies of men [summary adjusted RR, 2.7; 95% confidence interval (CI), 1.9-3.9] and women (RR, 3.1; 95% CI, 1.7-5.6), and among men who have sex with men (RR, 1.7; 95% CI, 1.2-2.4). The effect in high-risk women showed significant heterogeneity, with no overall evidence of an association.

CONCLUSIONS

Prevalent HSV-2 infection is associated with a three-fold increased risk of HIV acquisition among both men and women in the general population, suggesting that, in areas of high HSV-2 prevalence, a high proportion of HIV is attributable to HSV-2.

Metaanalysis and metaregression in interpreting study variability in the impact of sexually transmitted diseases on susceptibility to HIV infection

BACKGROUND

Observational studies examining the effects of other sexually transmitted diseases (STDs) on HIV susceptibility differ in the populations observed and in which "other STDs" are examined. The extent to which an STD alters the risk of transmission of HIV may vary according to disease and population characteristics.

GOALS

The goals of this study were to review studies examining the effect of other STDs on HIV-1 susceptibility and to correlate their effect estimates with type of "other STD", study design, and population characteristics.

STUDY

Relevant studies with longitudinal design were identified through a systematic search of the PubMed database, and their evidence was critically evaluated. Metaregression techniques were then used to correlate study characteristics with corresponding effect estimates.

RESULTS

Of 31 studies included, 4 contained direct data on exposure to HIV-1. Three of these were inconclusive, the fourth indicating a strong relationship between STDs and transmission of HIV. Pooled effect estimates using all studies are statistically significant and indicate a 2- to 3-fold increase in risk of HIV-1 acquisition. Effect estimates corresponding some of the "other STD" categories exhibit heterogeneity, but no significant associations with study characteristics were found.

CONCLUSIONS

Most of the studies lack direct exposure data, lending them susceptible to exposure bias. Another problem may be measurement error about risk factors and STD status at time of HIV-1 infection. Because direct exposure data are difficult to come by (4 of 31 studies contained such data, all but 1 inconclusive), future observational studies on the influence of STDs on HIV-1 transmission should include quantitative analyses of the sensitivity of results to potential confounding and measurement error if they are to further understanding.

Behavior Assessment of Blood Donors Facing the Risk of HIV Infection, Abidjan, Côte D'Ivoire, 2001-2002

Despite precautions taken to guarantee blood safety, in the National Blood Transfusion Center (CNTS) of Abidjan, about 30 regular blood donors are detected with HIV seroconversion each year, two-thirds of them men. A survey through face-to-face interviews was carried out at the CNTS of Abidjan from September 2001 to March 2002 among HIV-positive and HIV-negative regular blood donors, informed about their serologic status. HIV-negative regular blood donors informed about their serologic status since a median time of 67 months (n = 50) disclosed more risky behaviors such as multiple sexual partners (68%) than HIV-positive blood donors informed about their status (n = 112) since a median time of 35 months (41%) (P < 0.001). Condoms were systematically used by 17% of HIV-negative blood donors and 55% of HIV-positive blood donors (P < 0.001). Enhanced counseling and awareness could reduce in the future the number of cases of seroconversion among regular blood donors and improve their subsequent behavior. Blood donors who have unprotected sex with partners of unknown HIV serologic status and especially with casual partners are strongly exposed to HIV transmission and should be discouraged to continue giving blood, after adequate counseling.

HIV and Islam: is HIV prevalence lower among Muslims?

Religious constraints on sexuality may have consequences for the transmission of sexually transmitted diseases. Recognising that several Islamic tenets may have the effect, if followed, of reducing the sexual transmission of HIV, this paper tests the hypothesis that Muslims have lower HIV prevalence than non-Muslims. Among 38 sub-Saharan African countries, the percentage of Muslims within countries negatively predicted HIV prevalence. A survey of published journal articles containing data on HIV prevalence and religious affiliation showed that six of seven such studies indicated a negative relationship between HIV prevalence and being Muslim. Additional studies on the relationship of risk factors to HIV prevalence gave mixed evidence with respect to following Islamic sexual codes (e.g., vs. extramarital affairs) and other factors, but that benefits arising from circumcision may help account for lower HIV prevalence among Muslims.

Risk of HIV-1 in rural Kenya: a comparison of circumcised and uncircumcised men

BACKGROUND

Most studies that have found an association between uncircumcised status and infection with human immunodeficiency virus type 1 (HIV-1) have compared participants from various demographic backgrounds, among which the prevalence of other risk factors might have varied. We report findings from a study conducted among men within a single ethnic community in which circumcision was dictated by the religious denomination to which the men belonged.

METHODS

Of the 1217 eligible men, we included in the analysis 845 who gave blood samples for HIV-1 testing and who were confirmed as either fully circumcised (n = 398) or uncircumcised (n = 447). The seroprevalence of HIV-1 was compared between the 2 groups.

RESULTS

All correlates of HIV-1 prevalence that we measured were distributed similarly between circumcised and uncircumcised men. The seroprevalence of HIV-1 was 30% among the uncircumcised men and 20% among the circumcised men. Among uncircumcised men, HIV-1 seroprevalence was similar between men from circumcising denominations (31%; n = 111) and noncircumcising denominations (30%; n = 336). The crude prevalence ratio for HIV infection associated with not being circumcised was 1.5 (95% confidence interval = 1.2-2.0); and adjustment for other measured risk factors for HIV-1 infection had little impact on this result.

CONCLUSION

Our study provides evidence that circumcision is associated with a reduced risk of HIV-1 infection.

Spatial bridges for the importation of gonorrhea and chlamydial infection

A study of heterosexuals with gonorrhea and/or chlamydial infection in King County, Washington, found that 5.2% of study participants had both local and geographically distant sex partners in the 60 days before diagnosis. Individuals who served as spatial bridges were of higher socioeconomic status and older than other patients.

BACKGROUND

Sexual mixing between distant geographic areas (spatial bridging) is important in the spread of antimicrobial resistance and new sexually transmitted disease pathogens.

GOAL

The goal was to define the extent of sexual mixing between persons with gonorrhea or chlamydial infection in King County, Washington, and persons outside the Seattle area, and to identify characteristics of persons and partnerships associated with spatial bridging.

METHODS

Patients contacted for purposes of partner notification were interviewed regarding demographics, sexual behavior, and the characteristics of their sex partners.

RESULTS

Of 2912 participants, 150 (5.2%) were spatial bridgers. Bridgers were of higher socioeconomic status than nonbridgers and more often reported concurrent partnerships. Over a 39-month period, bridgers and potential bridgers linked King County with 35 states and 13 foreign countries.

CONCLUSION

Spatial bridging could represent an important channel of transmission between geographic areas. These results highlight the need for linkage of prevention efforts across geographic boundaries.

Increasing relative prevalence of HSV-2 infection among men with genital ulcers from a mining community in South Africa

OBJECTIVES

To determine the aetiology of genital ulcer disease (GUD) and its association with HIV infection in the mining community of Carletonville, South Africa, from two cross sectional surveys of consecutive men presenting with genital lesions during October 1993 to January 1994 and July to November 1998.

METHODS

A multiplex polymerase chain reaction (M-PCR) assay combined with amplicon detection was used to identify DNA specific sequences of Treponema pallidum, herpes simplex virus (HSV), and Haemophilus ducreyi. A real time PCR assay was used to differentiate between HSV-1 and HSV-2.

RESULTS

M-PCR detected T pallidum, HSV, and H ducreyi in 10.3%, 17.2%, and 69.4% of 232 GUD patients during 1993-4 and in 12.4%, 36.0%, and 50.5% of 186 GUD patients in 1998. The proportion of patients with more than one agent increased significantly from 7.3% (17/232) in 1993-4 to 16.7% (31/186) in 1998 (p <0.01). HSV-2 was detected in a higher proportion of ulcer specimens from HIV infected patients than in specimens from HIV uninfected patients during both time periods (1993-4: 26.2% v 6.7%, p <0.001; 1998: 42.1% v 29.6%, p >0.09).

CONCLUSIONS

Based on two cross sectional surveys, 4 years apart, chancroid remained the leading cause of GUD in men who presented at the STD clinic with genital ulcers in the mining community of Carletonville, South Africa. The relative prevalence of primary syphilis has remained low. However, HSV-2 has emerged as a more significant cause of GUD and the proportion of GUD patients infected with more than one agent also increased significantly. HSV-2 DNA was detected in a significantly higher proportion of ulcer specimens from HIV positive patients than from HIV negative patients. No association was found between HIV infection status and the relative prevalence of chancroid or syphilis.

Correlates of human herpesvirus 8 seropositivity among heterosexual men in Kenya

BACKGROUND

Several studies have suggested that sexual transmission of human herpesvirus 8 (HHV-8) occurs among homosexual men in developed countries. However, few studies have examined heterosexual HHV-8 transmission, especially among African populations in which HHV-8 is endemic.

OBJECTIVES

To determine the seroprevalence and correlates of HHV-8 infection among heterosexual African men.

DESIGN

Cross-sectional study.

METHODS

Participants were 1061 men enrolled in a prospective cohort study of risk factors for HIV-1 acquisition among trucking company employees in Mombasa, Kenya. Stored frozen sera from the study baseline visit were tested for antibodies to HHV-8 by whole-virus lysate ELISA.

RESULTS

HHV-8 seroprevalence was 43%. In multivariate logistic regression analysis, HHV-8 infection was independently associated with older age [for men aged 30-39 years: odds ratio (OR), 1.5; 95% confidence interval (CI), 1.1-2.0; for men aged > or = 40 years: OR, 1.7; 95% CI, 1.1-2.7, compared with men aged < 30 years], Christian religion (OR, 1.6; 95% CI, 1.2-2.1), being uncircumcised (OR, 1.5; 95% CI, 1.0-2.2), and ever having syphilis (OR, 2.2; 95% CI, 1.4-3.5). Ever having used condoms was associated with decreased likelihood of infection (OR, 0.7; 95% CI, 0.6-1.0). Seropositivity was not significantly related to other sexual behaviors characterized or to HIV-1 status.

CONCLUSIONS

HHV-8 seropositivity is common in this population and increases with age, suggesting on-going transmission during adulthood. Infection was more common among men who were uncircumcised or who had ever had syphilis and was less common among those who had ever used condoms, suggesting that sexual factors may play a role in HHV-8 transmission. Prospective studies of HHV-8 acquisition in heterosexual African populations are needed to demonstrate whether safer sexual practices can reduce transmission.

Age-specific prevalence of infection with herpes simplex virus types 2 and 1: a global review

Information on age- and sex-specific prevalence of herpes simplex virus (HSV) types 2 and 1 infections is essential to optimize genital herpes control strategies, which increase in importance because accumulating data indicate that HSV-2 infection may increase acquisition and transmission of human immunodeficiency virus. This review summarizes data from peer-reviewed publications of type-specific HSV seroepidemiologic surveys. HSV-2 prevalence is, in general, highest in Africa and the Americas, lower in western and southern Europe than in northern Europe and North America, and lowest in Asia. HSV-2 and -1 prevalence, overall and by age, varies markedly by country, region within country, and population subgroup. Age-specific HSV-2 prevalence is usually higher in women than men and in populations with higher risk sexual behavior. HSV-2 prevalence has increased in the United States but national data from other countries are unavailable. HSV-1 infection is acquired during childhood and adolescence and is markedly more widespread than HSV-2 infection. Further studies are needed in many geographic areas.

Herpes simplex virus type 2 infection increases HIV incidence: a prospective study in rural Tanzania

OBJECTIVES

To quantify the association between prevalent or incident Herpes simplex virus type-2 (HSV2) infection and the incidence of HIV seroconversion among adults in the general population in rural Tanzania.

STUDY POPULATION

Adults aged 15-54 years sampled randomly from 12 rural communities in Mwanza Region, Tanzania and recruited to a randomized trial of improved treatment of sexually transmitted diseases.

STUDY DESIGN

Unmatched case-control study nested within trial cohort.

METHODS

Participants included 127 cases who seroconverted to HIV during the 2-year follow-up period and 636 randomly selected controls who remained HIV negative. Subjects were tested for HSV2 serology at baseline and follow-up, and associations between HIV and HSV2 were analysed with adjustment for socio-demographic and behavioural factors.

RESULTS

After adjusting for confounding factors, a strong association between HSV2 infection and HIV seroconversion was observed in men (test for trend: P < 0.001), with adjusted odds ratios (OR) of 6.12 [95% confidence interval (CI), 2.52-14.9] in those HSV2 positive at baseline, and 16.8 (95% CI, 6.06-46.3) in those acquiring HSV2 infection during follow-up. A weaker association was observed in women (tests for trend: P = 0.14), with adjusted OR of 1.32 (95% CI, 0.62-2.78) and 2.36 (95% CI, 0.81-6.84), respectively. Population attributable fractions of incident HIV infection due to HSV2 were estimated as 74% in men and 22% in women.

CONCLUSIONS

The results suggest that HSV2 plays an important role in the transmission of HIV infection in this population. There is an urgent need to identify effective HSV2 control measures in order to reduce HIV incidence in Africa.

Estimating the magnitude of STD cofactor effects on HIV transmission: how well can it be done?

BACKGROUND

If sexually transmitted disease (STD) cofactor effects are strong and STDs are highly prevalent, STD control can be a strategy for HIV prevention.

OBJECTIVE

To review possibilities for estimating cofactor effects of STDs on HIV transmission based on observational studies.

STUDY DESIGN

This study consisted of an analysis of factors influencing associations between HIV and STDs, which can bias STD cofactor studies, from a sexual network perspective. Study designs that reduce distortions and methods to improve estimates in the presence of confounding are discussed.

RESULTS

Standard statistical adjustments of cofactor estimates are insufficient because they ignore clustering between HIV and STDs in partners of study subjects, resulting from population heterogeneity in risk factors and assortative mixing. Reverse causation due to HIV-related immunosuppression may further inflate cofactor estimates. Misclassification of STDs and clustering between STDs can bias estimates in either direction. This study demonstrates quantitatively that ignorance of sexual network effects may result in considerable overestimation of cofactor magnitudes.

CONCLUSION

The limitations of observational studies complicate quantitative inferences on the role of STDs in HIV transmission.