HSV-2 Incidence Research Articles

"I was just concerned about getting pregnant”: Attitudes toward pregnancy and contraceptive use among adolescent girls and young women in Thika, Kenya

BackgroundAdolescent girls and young women (AGYW) have a high incidence of unplanned pregnancies, especially in low-resource settings. AGYW assess the overlapping risks of pregnancy, contraception, and STIs as they navigate relationships. Few studies have examined how AGYW consider the comparative risks of their decisions around sexual and reproductive health in this context or how risk perception influences contraceptive use.MethodsTwenty in-depth interviews (IDIs) and 5 focus group discussions (FGDs) were conducted with a subset of sexually active AGYW enrolled in the Girls Health Study (GHS), a longitudinal cohort study in Thika, Kenya, assessing HSV-2 incidence in a cohort of AGYW aged 16–20. Interview questions were focused on perspectives and decision-making around sexual and reproductive health. Interviews were conducted in both English and Kiswahili, transcribed, and coded using inductive and deductive approaches to identify emerging themes.ResultsMisconceptions about long-acting reversible contraceptives (LARCs), injectables, and daily oral contraceptive pills strongly disincentivized their use among AGYW. Participants described pregnancy as undesirable, and AGYW reported prioritizing contraceptive methods that were effective and reliable in pregnancy prevention, even if not effective in preventing STI/HIV infection. Participants reported that AGYW relied heavily on emergency contraceptive (EC) pills for pregnancy prevention.ConclusionsThough the goal of avoiding unintended pregnancy was common, this did not suffice to motivate the uptake of long-term contraceptives among AGYWs. Given the convenience, cost-effectiveness, and lower perceived risk of side effects, EC pills were more likely to be accepted as a form of contraception. Understanding the reasons for AGYW’s acceptance of certain contraceptive methods over others can help future interventions better target communication and counseling about contraception and influence key drivers of AGYW behavior and decision-making around sexual and reproductive health.

Estimating HIV, HCV and HSV2 incidence from emergency department serosurvey

Background: Our understanding of pathogens and disease transmission has improved dramatically over the past 100 years, but coinfection, how different pathogens interact with each other, remains a challenge. Cross-sectional serological studies including multiple pathogens offer a crucial insight into this problem. Methods: We use data from three cross-sectional serological surveys (in 2003, 2007 and 2013) in a Baltimore emergency department to predict the prevalence for HIV, hepatitis C virus (HCV) and herpes simplex virus, type 2 (HSV2), in a fourth survey (in 2016). We develop a mathematical model to make this prediction and to estimate the incidence of infection and coinfection in each age and ethnic group in each year. Results: Overall we find a much stronger age cohort effect than a time effect, so that, while incidence at a given age may decrease over time, individuals born at similar times experience a more constant force of infection over time. Conclusions: These results emphasise the importance of age-cohort counselling and early intervention while people are young. Our approach adds value to data such as these by providing age- and time-specific incidence estimates which could not be obtained any other way, and allows forecasting to enable future public health planning.

Incidence of Herpes Simplex Virus Type 2 Infection Among African Women Using Depot Medroxyprogesterone Acetate, a Copper Intrauterine Device, or a Levonorgestrel Implant for Contraception: A Nested Randomized Trial

Background: Globally, women have higher herpes simplex type 2 (HSV-2) prevalence than men; data from observational studies suggest a possible association of HSV-2 acquisition with use of certain contraceptive methods, particularly intramuscular depot medroxyprogesterone acetate (DMPA-IM). Methods: Within a randomized trial of the effect of three contraceptive methods – DMPA-IM, a copper intrauterine device (IUD), and a levonorgestrel (LNG) implant – on HIV acquisition, we assessed HSV-2 acquisition. We followed women who were HSV-2 and HIV seronegative, aged 16-35 years, and seeking effective contraception for 12-18 months at 12 sites in Eswatini, Kenya, South Africa, and Zambia from 2015-2018. HSV-2 serologic testing was done at enrollment and final study visits according to a standardized algorithm. Intention–to-treat analysis using Poisson regression with robust standard errors compared HSV-2 incidence by contraceptive method. Findings: At baseline, 4062 randomized women were HSV-2 seronegative, of whom 3898 (96.0%) had a conclusive HSV-2 result at their final study visit. Of these, 614 (15.8%) acquired HSV-2, at an incidence of 12.4/100 person-years (p-y): 10.9/100 p-y among women assigned DMPA-IM, 13.7/100 p-y the copper IUD, and 12.7/100 p-y the LNG implant. Incidence rate ratios (IRR) for HSV-2 acquisition were 0.80 (95% confidence interval [CI] 0.65-0.97) for DMPA-IM compared with copper IUD, 0.86 (95% CI 0.71-1.05) for DMPA-IM compared with LNG implant, and 1.08 (95% CI 0.89-1.30) for copper IUD compared with LNG implant. HSV-2 acquisition risk was significantly increased among women who also acquired HIV during follow-up (IRR 3.55, 95% CI 2.78-4.48). Interpretation: In a randomized trial, DMPA-IM was not associated with increased risk of HSV-2 acquisition. HSV-2 incidence was >10% per year, emphasizing the need for development of novel HSV-2 prevention strategies for African women. Clinical Trial Registration Details: ClinicalTrials.gov number NCT02550067. Funding Information: The ECHO Trial was made possible by the combined generous support of the Bill & Melinda Gates Foundation, the American people through the United States Agency for International Development and the President’s Emergency Plan for AIDS Relief, the Swedish International Development Cooperation Agency as part of the EDCTP2 programme supported by the European Union, the South African Medical Research Council, and the United Nations Population Fund. Contraceptive supplies were donated by the Government of South Africa and United States Agency for International Development. Additional funding for testing for herpes simplex type 2 infection was provided in part by the US Centers for Disease Control and Prevention (U48 DP 005013 SIP 14-023) and the University of Washington/Fred Hutch Center for AIDS Research (US National Institutes of Health P30 AI057757). Declaration of Interests: None. Ethics Approval Statement: Ethics review committees at each study site approved the study protocol. All participants provided written informed consent, which included counseling about randomization, each study contraceptive method, and their rights as research participants.

Effect of On-Demand Oral Pre-exposure Prophylaxis With Tenofovir/Emtricitabine on Herpes Simplex Virus-1/2 Incidence Among Men Who Have Sex With Men: A Substudy of the ANRS IPERGAY Trial.

We evaluated the impact of on-demand oral tenofovir disoproxil fumarate (TDF)/emtricitabine (FTC) for pre-exposure prophylaxis (PrEP) on herpes simplex virus (HSV)-1/2 incidence among men who have sex with men (MSM) enrolled in the ANRS IPERGAY trial. Serum samples were tested at baseline and at the last visit for HSV-1/2 antibodies. Overall HSV-1 incidence was 11.7 per 100 person-years; 16.2 and 7.8 per 100 person-years in the TDF/FTC and placebo arm, respectively (P = .19). Overall HSV-2 incidence was 7.6 per 100 person-years; 8.1 and 7.0 per 100 person-years in the TDF/FTC and placebo arm, respectively (P = .75). On-demand oral PrEP with TDF/FTC failed to reduce HSV-1/2 incidence in this population.

Microbial Diversity of Genital Ulcers of HSV-2 Seropositive Women

We measured the microbial community structure of genital ulcers in women. Swabs from clinically detected ulcers were tested for HSV-2 and Treponema pallidum by polymerase chain reaction (PCR). HSV-2 and T. pallidum were detected by serum antibody testing. Microbial community structure was characterized by high-throughput 16 s rRNA gene amplicon sequencing. Multiple group testing and Elastic net and Lasso regressions identified taxa associated with differences in factors of interest. Among 49 ulcer specimens from 49 HSV-2 seropositive women, by PCR HSV-2 was recovered from 28 (57%) specimens and T. pallidum from none; one woman showed serologic evidence of syphilis. Overall, 63% of women were HIV-positive and 49% had an uncircumcised male sex partner. By both multiple group testing and regression, Porphyromonas (FDR p-value = 0.02), Prevotella (FDR p-value = 0.03), Anaerococcus (FDR p-value = 0.07), and Dialister (FDR p-value = 0.09) were detected at higher relative abundance in HSV-2 PCR-positive than negative ulcers. The presence of HSV-2 in a lesion was associated with presumed bacterial agents of Bacterial vaginosis. Differences in bacterial communities may contribute to HSV-2 ulcer pathogenesis, severity, or prolonged healing. If these results are confirmed, future studies may consider the influence of BV treatment on women’s GUD and HSV-2 incidence and recurrence.

Prevalence, incidence and correlates of HSV-2 infection in an HIV incidence adolescent and adult cohort study in western Kenya.

BackgroundHerpes simplex virus type 2 (HSV-2) infections are associated with increased risk of HIV transmission. We determined HSV-2 prevalence, incidence and associated risk factors, incidence among persons with indeterminate results, and prevalence of HSV-2/HIV co-infection among young adults (18–34 years) and adolescents (16–17 years) enrolled in an HIV incidence cohort study in western Kenya.MethodsParticipants (n = 1106; 846 adults) were screened and those HIV-1 negative were enrolled and followed-up quarterly for one year. HSV-2 was assessed using the Kalon enzyme immunoassay. HSV-2 incidence was calculated separately among HSV-2 seronegative participants and those indeterminate at baseline. Logistic regression was used to estimate the odds of HSV-2 infection and Poisson regression was used to assess HSV-2 incidence and associated factors.ResultsOverall, HSV-2 prevalence was 26.6% [95% confidence interval (CI): 23.9–29.4] and was higher in adults (31.5% [95% CI: 28.3–34.9]) than adolescents (10.7% [95% CI: 7.1–15.3]). Factors associated with prevalent HSV-2 included female gender, increasing age, HIV infection, history of sexually transmitted infection, low level of education, multiple sexual partners, and being married, divorced, separated or widowed. Overall HSV-2 incidence was 4.0 per 100 person-years (/100PY) 95% CI: 2.7–6.1 and was higher in adults (4.5/100PY) and females (5.1/100PY). In multivariable analysis only marital status was associated with HSV-2 incidence. Among 45 participants with indeterminate HSV-2 results at baseline, 22 seroconverted, resulting in an incidence rate of 53.2 /100PY [95% CI: 35.1–80.9]. Inclusion of indeterminate results almost doubled the overall incidence rate to 7.8 /100 PY [95% CI: 5.9–10.5]. Prevalence of HIV/HSV-2 co-infection was higher in female adults than female adolescents (17.1 [95% CI: 13.6–21.0] versus 3.4 [95% CI: 1.1–7.8]).ConclusionThe high incidence rate among persons with indeterminate results underscores the public health concerns for HSV-2 spread and underreporting of the HSV-2 burden. Careful consideration is needed when interpreting HSV-2 serology results in these settings.

Prevalence and incidence estimation of HSV-2 by two IgG ELISA methods among South African women at high risk of HIV.

IntroductionPrevious comparison studies of the Kalon and HerpeSelect 2 ELISA IgG assays on sub-Saharan samples have found differences in the sensitivity and specificity of these assays. Using longitudinal samples from an HIV prevention study, we compared both assays and determined the HSV-2 prevalence and incidence in a South African young female population at elevated risk of acquiring HIV.MethodsSamples at baseline were tested in both assays using the manufacturers’ guidelines (cut-off > 1.10). When non-reactive in one assay, the final visit samples were tested to determine the incidence rate. Using correlation and regression analyses, the intra- and inter-assay variabilities were assessed.ResultsThe prevalence rate was 41.1% and 44.9% for Kalon and HerpeSelect using the manufacturer guidelines, respectively. Agreement between the two tests were high (kappa = 0.92). The original optical density values of both assays were highly correlated (R = 0.94), but the calibrator and correspondingly cut-off index values differed between the assays. Lowering the index value cut-off for the Kalon assay by 40% (to 0.66) resulted in a HSV-2 prevalence of 43.2%, and increased agreement between the assays (to kappa = 0.96). The incidence rate was 16.3/100 Person Years using the lower cut-off for the Kalon assay.DiscussionIn this longitudinal study, we showed that the performance of the two assays was very similar. After lowering the cut-off for the Kalon assay to 0.66 early infections were detected without impairing its specificity. The prevalence and incidence rates are in line with previously described rates for sub-Saharan African cohorts.

Estimating the cost-effectiveness of pre-exposure prophylaxis to reduce HIV-1 and HSV-2 incidence in HIV-serodiscordant couples in South Africa.

ObjectiveTo estimate the cost-effectiveness of daily oral tenofovir-based PrEP, with a protective effect against HSV-2 as well as HIV-1, among HIV-1 serodiscordant couples in South Africa.MethodsWe incorporated HSV-2 acquisition, transmission, and interaction with HIV-1 into a microsimulation model of heterosexual HIV-1 serodiscordant couples in South Africa, with use of PrEP for the HIV-1 uninfected partner prior to ART initiation for the HIV-1 1infected partner, and for one year thereafter.ResultsWe estimate the cost per disability-adjusted life-year (DALY) averted for two scenarios, one in which PrEP has no effect on reducing HSV-2 acquisition, and one in which there is a 33% reduction. After a twenty-year intervention, the cost per DALY averted is estimated to be $10,383 and $9,757, respectively – a 6% reduction, given the additional benefit of reduced HSV-2 acquisition. If all couples are discordant for both HIV-1 and HSV-2, the cost per DALY averted falls to $1,445, which shows that the impact is limited by HSV-2 concordance in couples.ConclusionAfter a 20-year PrEP intervention, the cost per DALY averted with a reduction in HSV-2 is estimated to be modestly lower than without any effect, providing an increase of health benefits in addition to HIV-1 prevention at no extra cost. The small degree of the effect is in part due to a high prevalence of HSV-2 infection in HIV-1 serodiscordant couples in South Africa.

Global estimates of prevalent and incident herpes simplex virus type 2 infections in 2012.

BackgroundHerpes simplex virus type 2 (HSV-2) infection causes significant disease globally. Adolescent and adult infection may present as painful genital ulcers. Neonatal infection has high morbidity and mortality. Additionally, HSV-2 likely contributes substantially to the spread of HIV infection. The global burden of HSV-2 infection was last estimated for 2003. Here we present new global estimates for 2012 of the burden of prevalent (existing) and incident (new) HSV-2 infection among females and males aged 15–49 years, using updated methodology to adjust for test performance and estimate by World Health Organization (WHO) region.Methods and FindingsWe conducted a literature review of HSV-2 prevalence studies world-wide since 2000. We then fitted a model with constant HSV-2 incidence by age to pooled HSV-2 prevalence values by age and sex. Prevalence values were adjusted for test sensitivity and specificity. The model estimated prevalence and incidence by sex for each WHO region to obtain global burden estimates. Uncertainty bounds were computed by refitting the model to reflect the variation in the underlying prevalence data. In 2012, we estimate that there were 417 million people aged 15–49 years (range: 274–678 million) living with HSV-2 infection world-wide (11.3% global prevalence), of whom 267 million were women. We also estimate that in 2012, 19.2 million (range: 13.0–28.6 million) individuals aged 15–49 years were newly-infected (0.5% of all individuals globally). The highest burden was in Africa. However, despite lower prevalence, South-East Asia and Western Pacific regions also contributed large numbers to the global totals because of large population sizes.ConclusionsThe global burden of HSV-2 infection is large, leaving over 400 million people at increased risk of genital ulcer disease, HIV acquisition, and transmission of HSV-2 to partners or neonates. These estimates highlight the critical need for development of vaccines, microbicides, and other new HSV prevention strategies.

Population and dyadic-based seroincidence of herpes simplex virus-2 and syphilis in southern India

ObjectivesHerpes simplex virus-2 (HSV-2) and syphilis are associated with increased risk of HIV, highlighting the importance of understanding their transmission dynamics. In India, most studies of HSV-2 and syphilis incidence...

Incidence and prevalence of herpes simplex virus type-2 infections among fishermen in Kisumu, Kenya

Background: Men with high-risk sexual behavior are important drivers of HIV/STIs in the general population. Prevention of HIV/STIs among suchmen could potentially reduce these infections among women who bear the greatest HIV/STIs disease burden. HSV-2 infection has been shown to be strongly associatedwith HIV infections. We sought to estimate the incidence of HSV-2 infection among fishermen. MethodsM 183 (61%) P<0.01 and 118 (39%) P<0.05, never used condoms with their frequent sexual partners and new sexual partners respectively. Baseline HSV-2 prevalence was 56.3% and married men were 3 times more likely to have HSV-2 infections compared to single (never married) men adjOR 3.2(95% CI; 1.8-5.5), P <0.001. HIV positive men were twice more likely to be co-infected with HSV-2 compared to HIV negativemen adjOR 2.2(95% CI; 1.2-4.2). At baseline, menwho reported only one sexual partner in the last one month were less likely to have HSV-2 infections compared to those who reported multiple sexual partners for the same period adjOR 0.09(95% CI; 0.01-0.74). The annual HSV-2 incidencewas 23.6%. HSV-2 negativemen reporting a casual partner as their most recent sexual partner at baseline had increased risk of HSV-2 acquisition adjRR 6.7(95% CI; 2.4-18.1). Those reporting consistent condom use of over 75% at baseline had reduced risk of acquiring HSV-2 adjRR 0.12(95% CI; 0.03-0.54) P <0.01, whereas those who reported no condom use (0% usage) had increased risk of acquiring HSV-2 adjRR 3.2(95% CI; 1.3-7.9), P <0.01. Multiple number of sexual partners in the past 1 year was strongly associated with incident HSV-2 infection, P <0.01. Conclusion: Fishermen comprise a young sexually-high-risk population, with high HSV-2 incidence and prevalence. Low condom use coupled with concurrent multiple sexual partnerships predispose fishermen to HSV-2 infections.

Cost-effectiveness of tenofovir gel in urban South Africa: model projections of HIV impact and threshold product prices

BackgroundThere is urgent need for effective HIV prevention methods that women can initiate. The CAPRISA 004 trial showed that a tenofovir-based vaginal microbicide had significant impact on HIV incidence among women. This study uses the trial findings to estimate the population-level impact of the gel on HIV and HSV-2 transmission, and price thresholds at which widespread product introduction would be as cost-effective as male circumcision in urban South Africa.MethodsThe estimated ‘per sex-act’ HIV and HSV-2 efficacies were imputed from CAPRISA 004. A dynamic HIV/STI transmission model, parameterised and fitted to Gauteng (HIV prevalence of 16.9% in 2008), South Africa, was used to estimate the impact of gel use over 15 years. Uptake was assumed to increase linearly to 30% over 10 years, with gel use in 72% of sex-acts. Full economic programme and averted HIV treatment costs were modelled. Cost per DALY averted is estimated and a microbicide price that equalises its cost-effectiveness to that of male circumcision is estimated.ResultsUsing plausible assumptions about product introduction, we predict that tenofovir gel use could lead to a 12.5% and 4.9% reduction in HIV and HSV-2 incidence respectively, by year 15. Microbicide introduction is predicted to be highly cost-effective (under $300 per DALY averted), though the dose price would need to be just $0.12 to be equally cost-effective as male circumcision. A single dose or highly effective (83% HIV efficacy per sex-act) regimen would allow for more realistic threshold prices ($0.25 and $0.33 per dose, respectively).ConclusionsThese findings show that an effective coitally-dependent microbicide could reduce HIV incidence by 12.5% in this setting, if current condom use is maintained. For microbicides to be in the range of the most cost-effective HIV prevention interventions, product costs will need to decrease substantially.

Effect of HSV‐2 on population‐level trends in HIV incidence in Uganda between 1990 and 2007

Objective To assess the long-term effects of population-level HSV-2 infection on HIV incidence.Methods Data from a population-based cohort in south-western Uganda were used to estimate HIV incidence from 1990 to 2007. Stored blood samples were tested for HSV-2, and the impact of HSV-2 prevalence and incidence on HIV incidence was estimated by calculating population attributable fractions (PAFs). The association between population-level annual HIV incidence and annual HSV-2 incidence/prevalence was analysed using linear regression.Results HIV incidence declined over time among men, from 8.72/1000 person-years (pyr) in 1990 to 4.85/1000 pyr in 2007 (P-trend <0.001). In contrast, there was no decline in HIV incidence among women (4.86/1000 pyr in 1990 to 6.74/1000 pyr in 2007, P-trend = 0.18). PAFs of incident HIV attributable to HSV-2 were high (60% in males; 70% in females). There was no evidence of an association between long-term trends in HIV incidence and HSV-2 prevalence or incidence.Conclusion Assuming a causal relationship, a substantial proportion of new HIV infections in this population are attributable to HSV-2. The study did not find an effect of HSV-2 prevalence/incidence on trends in HIV incidence. HIV incidence did not vary much during the study period. This may partly explain the lack of association.

The epidemiology of HIV and HSV-2 infections among women participating in microbicide and vaccine feasibility studies in Northern Tanzania.

ObjectivesTo prepare for future HIV prevention trials, we conducted prospective cohort studies among women working in food and recreational facilities in northern Tanzania. We examined the prevalence and incidence of HIV and HSV-2, and associated risk factors.MethodsWomen aged 18–44 years working in food and recreational facilities were screened to determine their eligibility for the studies. Between 2008–2010, HIV-negative women were enrolled and followed for 12 months. At enrolment and 3-monthly, we collected socio-demographic and behavioural data, and performed clinical examinations for collection of biological specimens that were tested for reproductive tract infections. Risk factors for HIV and HSV-2 incidence were investigated using Poisson regression models.ResultsWe screened 2,229 and enrolled 1,378 women. The median age was 27 years (interquartile range, IQR 22, 33), and median duration working at current facility was 2 years. The prevalences of HIV at screening and HSV-2 at enrolment were 16% and 67%, respectively. Attendance at the 12-month visit was 86%. HIV and HSV-2 incidence rates were 3.7 (95% confidence interval, CI: 2.8,5.1) and 28.6 (95% CI: 23.5,35.0)/100 person-years, respectively. Women who were separated, divorced, or widowed were at increased risk of HIV (adjusted incidence rate ratio, aRR = 6.63; 95% CI: 1.97,22.2) and HSV-2 (aRR = 2.00; 95% CI: 1.15,3.47) compared with married women. Women reporting ≥3 partners in the past 3 months were at higher HIV risk compared with women with 0–1 partner (aRR = 4.75; 95% CI: 2.10,10.8), while those who had reached secondary education or above were at lower risk of HSV-2 compared with women with incomplete primary education (aRR = 0.42; 95% CI: 0.22,0.82).ConclusionsHIV and HSV-2 rates remain substantially higher in this cohort than in the general population, indicating urgent need for effective interventions. These studies demonstrate the feasibility of conducting trials to test new interventions in this highly-mobile population.

P3.055 Herpes Simplex Type 2 (HSV-2) Incidence by Age and Sex Over Four Age Periods to Age 38 Years in a Birth Cohort

BackgroundHere we report direct measures of HSV-2 incidence over four age periods to age 38 in the Dunedin Multidisciplinary Health and Development Study, a long-running New Zealand birth cohort.MethodsInformation on...

P1-S5.04 HSV-2 Prevalence and Incidence among Stable HIV-1 Discordant Couples in Nairobi, Kenya

BackgroundTo describe HSV-2 prevalence, incidence and their correlates among stable HIV-1 discordant heterosexual couples enrolled in an HIV-1 prevention cohort study in Nairobi, Kenya.MethodsBetween 2007 and 2009, 469 HIV-1 discordant...

Are women who work in bars, guesthouses and similar facilities a suitable study population for vaginal microbicide trials in Africa?

BackgroundA feasibility study was conducted to investigate whether an occupational at-risk cohort of women in Mwanza, Tanzania are a suitable study population for future phase III vaginal microbicide trials.Methodology/Principal Findings1573 women aged 16–54 y working in traditional and modern bars, restaurants, hotels, guesthouses or as local food-handlers were enrolled at community-based reproductive health clinics, provided specimens for HIV/STI and pregnancy testing, and asked to attend three-monthly clinical follow-up visits for 12-months. HIV positive and negative women were eligible to enter the feasibility study and to receive free reproductive health services at any time. HIV prevalence at baseline was 26.5% (417/1573). HIV incidence among 1156 sero-negative women attending at baseline was 2.9/100PYs. Among 1020 HIV sero-negative, non-pregnant women, HIV incidence was 2.0/100PYs, HSV-2 incidence 12.7/100PYs and pregnancy rate 17.8/100PYs. Retention at three-months was 76.3% (778/1020). Among 771 HIV sero-negative, non-pregnant women attending at three-months, subsequent follow-up at 6, 9 and 12-months was 83.7%, 79.6%, and 72.1% respectively. Older women, those who had not moved home or changed their place of work in the last year, and women working in traditional bars or as local food handlers had the highest re-attendance.Conclusions/SignificanceWomen working in food outlets and recreational facilities in Tanzania and other parts of Africa may be a suitable study population for microbicide and other HIV prevention trials. Effective locally-appropriate strategies to address high pregnancy rates and early losses to follow-up are essential to minimise risk to clinical trials in these settings.

The prevalence, incidence and risk factors of herpes simplex virus type 2 infection among pregnant Zimbabwean women followed up nine months after childbirth

BackgroundHerpes simplex virus type 2 (HSV-2) is the leading cause of genital ulcer disease worldwide. The virus can be transmitted to neonates and there are scarce data regarding incidence of HSV-2 among women in pregnancy and after childbirth. The aim of this study is to measure the incidence and risk factors for HSV-2 infection in women followed for 9 months after childbirth.MethodsPregnant women were consecutively enrolled late in pregnancy and followed at six weeks, four and nine months after childbirth. Stored samples were tested for HSV-2 at baseline and again at nine months after childbirth and HSV-2 seropositive samples at nine months after childbirth (seroconverters) were tested retrospectively to identify the seroconversion point.ResultsOne hundred and seventy-three (50.9%) of the 340 consecutively enrolled pregnant women were HSV-2 seronegative at baseline. HSV-2 incidence rate during the 10 months follow up was 9.7 (95% CI 5.4-14.4)/100 and 18.8 (95% CI 13.9-26.1)/100 person years at risk (PYAR) at four months and nine months after childbirth respectively. Analysis restricted to women reporting sexual activity yielded higher incidence rates. The prevalence of HSV-2 amongst the HIV-1 seropositive was 89.3%. Risk factors associated with HSV-2 seropositivity were having other sexual partners in past 12 months (Prevalence Risk Ratio (PRR) 1.8 (95% CI 1.4-2.4) and presence of Trichomonas vaginalis (PRR 1.7 95% CI 1.4-2.1). Polygamy (Incidence Rate Ratio (IRR) 4.4, 95% CI 1.9-10.6) and young age at sexual debut (IRR 3.6, 95% CI 1.6-8.3) were associated with primary HSV-2 infection during the 10 months follow up.ConclusionsIncidence of HSV-2 after childbirth is high and the period between late pregnancy and six weeks after childbirth needs to be targeted for prevention of primary HSV-2 infection to avert possible neonatal infections.

Screening for HSV-2 Infection in STD Clinics and Beyond: A Few Answers But More Questions

Screening for HSV-2 Infection in STD Clinics and Beyond: A Few Answers But More Questions

Riddle of the Sphinx Revisited: The Role of STDs in HIV Prevention

Riddle of the Sphinx Revisited: The Role of STDs in HIV Prevention