Detection of HSV-2 in genital ulcers from STD patients in Dar es Salaam, Tanzania

Herpes simplex virus type 1 epidemiology in Africa: Systematic review, meta-analyses, and meta-regressions

OBJECTIVE

To assess herpes simplex virus type 1 (HSV-1) epidemiology in Africa.

METHODS

This systematic review was conducted per the Cochrane Collaboration guidelines. Findings were reported following the PRISMA guidelines. Research questions were addressed using random-effects meta-analyses and meta-regressions.

RESULTS

Forty-three overall (and 69 stratified) HSV-1 seroprevalence measures, and 18 and eight proportions of HSV-1 viral detection in genital ulcer disease (GUD) and in genital herpes, respectively, were extracted from 37 reports. Pooled mean seroprevalence was 67.1% (95% confidence interval (CI): 54.7-78.5%) in children, and 96.2% (95% CI: 95.0-97.3%) in adults. Across age groups, pooled mean was 44.4% (95% CI: 29.9-59.3%) in ≤5 years-old, 85.6% (95% CI: 81.0-89.6%) in 6-15 years-old, 93.3% (95% CI: 89.2-96.6%) in 16-25 years-old, and 93.8% (95% CI: 84.6-99.4%) in >25 years-old. Age explained 78.8% of seroprevalence variation. Pooled mean proportion of HSV-1 detection was 0.4% (95% CI: 0.0-1.5%) in GUD, and 1.2% (95% CI: 0.0-4.0%) in genital herpes.

CONCLUSIONS

HSV-1 is universally prevalent in Africa, at higher levels than other regions, with no evidence for declines in seroprevalence in recent decades. Nearly every person acquires the infection in childhood through oral-to-oral transmission, before sexual debut. Sexual oral-to-genital and genital-to-genital transmission appear very limited.

Prevalence and risk factors for skin diseases among antiretroviral-naïve HIV-infected pregnant women in Dar es Salaam, Tanzania

BACKGROUND

Reduced cell-mediated immunity associated with pregnancy may cause a flaring or exacerbation of some skin conditions. Little is known about the magnitude of and risk factors for skin diseases among human immunodeficiency virus (HIV)-infected antiretroviral therapy-naïve pregnant women.

METHODS

Cross-sectional study of 1078 HIV-infected antiretroviral therapy-naïve pregnant women was conducted in Dar es Salaam, Tanzania. Skin diagnoses were mainly clinical. Log-binomial regression models were used to explore factors associated with the outcomes.

RESULTS

About 84% of the women were in World Health Organization (WHO) HIV stage I. Median CD4(+) count was 405 × 10(6)  cells/l. The prevalence of any skin disease was 18%. Fungal infections (11%), genital ulcers (7%), and viral infections (5%) were the most common skin conditions. Skin infections were 2.64 times more common in HIV stage III (95% CI 1.51-4.62) compared to stage I. Fungal infections were 1.77 times common among single, divorced, and widowed women than among married women (95% CI 1.16-2.69), 2.8 times common among women in HIV stage III (95% CI 1.18-6.64) compared to stage I. Genital ulcers were significantly more common among women whose source of income was their own compared with those who got full support from partners, and among WHO HIV stage III disease compared to stage I.

CONCLUSION

The burden of skin diseases was relatively low. Advanced HIV stage was associated with a range of skin conditions. CD4(+) cell count was not related to skin infection prevalence.

Current thinking on genital herpes

PURPOSE OF REVIEW

Genital herpes has a high global prevalence and burden of disease. This manuscript highlights recent advances in our understanding of genital herpes simplex virus (HSV) infections.

RECENT FINDINGS

Studies demonstrate a changing epidemiological landscape with an increasing proportion of genital herpes cases associated with HSV type 1. There is also growing evidence that the majority of infected individuals exhibit frequent, brief shedding episodes that are most often asymptomatic, which likely contribute to high HSV transmission rates. Given this finding as well as readily available serological assays, some have proposed that routine HSV screening be performed; however, this remains controversial and is not currently recommended. Host immune responses, particularly local CD4 and CD8 T cell activity, are crucial for HSV control and clearance following initial infection, during latency and after reactivation. Prior HSV immunity may also afford partial protection against HSV reinfection and disease. Although HSV vaccine trials have been disappointing to date and existing antiviral medications are limited, novel prophylactic and therapeutic modalities are currently in development.

SUMMARY

Although much remains unknown about genital herpes, improved knowledge of HSV epidemiology, pathogenesis and host immunity may help guide new strategies for disease prevention and control.

Possible reasons for an increase in the proportion of genital ulcers due to herpes simplex virus from a cohort of female bar workers in Tanzania

OBJECTIVES

To determine trends in the prevalence and aetiological distribution of genital ulcer syndrome (GUS) in a cohort of female bar workers and to assess factors associated with these trends.

METHODS

An open cohort of 600 women at high risk of HIV and sexually transmitted infection (STI) was offered screening and treatment for STI at 3-month intervals. The prevalence of GUS and associated aetiological agents (Herpes simplex virus (HSV), Treponema pallidum and Haemophilus ducreyi) were monitored over 27 months through clinical examination, dry lesion swabbing and multiplex polymerase chain reaction. The effects of HIV status and other factors on the prevalence trends of STI were assessed.

RESULTS

A total of 753 women were recruited into the cohort over 10 examination rounds. At recruitment, the seroprevalence was 67% for HIV and 89% for HSV type 2 (HSV-2). During follow-up, 57% of ulcers had unknown aetiology, 37% were due to genital herpes and 6% to bacterial aetiologies, which disappeared completely in later rounds. The absolute prevalence of genital herpes remained stable at around 2%. The proportion of GUS caused by HSV increased from 22% to 58%, whereas bacterial causes declined. These trends were observed in both HIV-negative and HIV-positive women.

CONCLUSIONS

The changes observed in the frequency and proportional distribution of GUS aetiologies suggest that regular STI screening and treatment over an extended period can effectively reduce bacterial STI and should therefore be sustained. However, in populations with a high prevalence of HSV-2, there remains a considerable burden of genital herpes, which soon becomes the predominant cause of GUS. Given the observed associations between genital herpes and HIV transmission, high priority should be given to the evaluation of potential interventions to control HSV-2 either through a vaccine or through episodic or suppressive antiviral therapy and primary prevention.

Atypical cutaneous manifestation of HSV-2 with Candida albicans co-infection in a patient with HIV-1

Herpes simplex virus type 2 (HSV-2) infection was one of the first opportunistic infections identified among patients with AIDS. In the literature there are many data suggesting that the natural history of HSV-2 infection is altered in HIV-HSV-2 co-infected patients. Furthermore, a relationship between HIV seropositivity and HBV infection because of their analogous way of transmission is also described. We report the case of a 37-year-old patient who suffered from multiple painful ulcerative lesions of the perianal region. Laboratory examination showed positivity for HIV and HBV infections. In HIV-positive patients perianal HSV-2 can have atypical manifestations, especially if co-infection by Candida albicans occurs.

Herpes simplex virus type 2: epidemiology and management options in developing countries

Genital herpes simplex virus type 2 (HSV2) is highly prevalent worldwide and an increasingly important cause of genital ulcer disease (GUD). Continued HSV2 transmission is facilitated by the large number of undiagnosed cases, the frequency of atypical disease and the occurrence of asymptomatic shedding. The lack of easy, affordable diagnostic methods and specific antiviral treatment in countries with low and middle income is of great concern, given the ability of GUD to enhance HIV transmission and acquisition. With rising HSV2 prevalence contributing to an increase in the proportion of GUD attributed to genital herpes in high-HIV prevalence settings, a safe and effective HSV vaccine is urgently needed. Meanwhile, multifaceted interventions are required to improve recognition of genital herpes, to prevent its spread and also to prevent its potential to promote HIV transmission in developing countries.

Mature glycoprotein g presents high performance in diagnosing herpes simplex virus type 2 infection in sera of different tanzanian cohorts

Herpes simplex virus type 2 (HSV-2) is a common sexually transmitted infection in sub-Saharan Africa. Glycoprotein G (gG) of HSV-2 elicits a type-specific antibody response and is widely used for serodiagnosis. gG is cleaved into a secreted portion (sgG-2) and a highly O-glycosylated mature portion (mgG-2). The performances of these two native immunosorbent purified antigens were compared in an enzyme-linked immunosorbent assay (ELISA) format with a commercially available assay (FOCUS2) using sera from blood donors (n = 194) and individuals (n = 198) with genital ulcer disease (GUD) from Tanzania. Discordant results were resolved by Western blotting. The HSV-2 seroprevalence for blood donors was estimated as 42%, and that for the GUD cohort was estimated as 78%. The prevalence increased significantly with age for both cohorts and was higher among human immunodeficiency virus (HIV)-positive individuals than among HIV-negative subjects. In the GUD cohort with a high HSV-2 prevalence, all three assays showed statistically similar performances, with sensitivities between 97% and 99% and specificities in the range of 86% to 91%. In contrast, among blood donors with a lower seroprevalence, the mgG-2-based ELISA presented significantly higher specificity (97%) than the sgG-2 ELISA (89%) and FOCUS2 (74%). Overall, the mgG-2 ELISA gave a high performance, with negative and positive predictive values of 96% for blood donors and a negative predictive value of 95% and a positive predictive value of 97% for the GUD cohort. We conclude that native purified mgG-2 showed the highest accuracy for detection of HSV-2 in patient sera from Tanzania and is therefore suitable for seroprevalence studies as well as in clinical settings.

Antiviral agents for the prevention of the sexual transmission of herpes simplex in discordant couples

PURPOSE OF REVIEW

The aim of this review is to summarize recent developments in our understanding of the modifiable behavioural and biological factors contributing to the transmission of genital herpes simplex infection, and the limited data on the use of antiviral agents for reducing transmission risk in serodiscordant couples.

RECENT FINDINGS

With the developing herpes simplex virus epidemic, the significance of biological and behavioural factors for the acquisition and transmission of genital herpes infection are increasingly recognized as important. Studies looking at the modification of behavioural factors indicate that knowledge of disease status, disease recognition and the promotion of condoms appears to modify transmission risk. However, these effects are disputed and their value is likely to be limited. In the absence of effective prophylactic vaccines, the reduction of clinical and subclinal herpes simplex virus shedding with the use of antiviral agents is an attractive option. A large study recently reported on the value of once daily valaciclovir for the prevention of transmission of genital herpes infection in serodiscordant couples. The study showed that continuous suppressive therapy not only controls symptomatic disease in the source partner, but reduces the likelihood of disease in the susceptible partner by between 48 and 75%. These findings will have a major impact on clinical practice. Questions remain, however, on whether these results can be extended to non-heterosexual populations and to drugs other then valaciclovir.

Once-daily valacyclovir to reduce the risk of transmission of genital herpes

BACKGROUND

Nucleoside analogues against herpes simplex virus (HSV) have been shown to suppress shedding of HSV type 2 (HSV-2) on genital mucosal surfaces and may prevent sexual transmission of HSV.

METHODS

We followed 1484 immunocompetent, heterosexual, monogamous couples: one with clinically symptomatic genital HSV-2 and one susceptible to HSV-2. The partners with HSV-2 infection were randomly assigned to receive either 500 mg of valacyclovir once daily or placebo for eight months. The susceptible partner was evaluated monthly for clinical signs and symptoms of genital herpes. Source partners were followed for recurrences of genital herpes; 89 were enrolled in a substudy of HSV-2 mucosal shedding. Both partners were counseled on safer sex and were offered condoms at each visit. The predefined primary end point was the reduction in transmission of symptomatic genital herpes.

RESULTS

Clinically symptomatic HSV-2 infection developed in 4 of 743 susceptible partners who were given valacyclovir, as compared with 16 of 741 who were given placebo (hazard ratio, 0.25; 95 percent confidence interval, 0.08 to 0.75; P=0.008). Overall, acquisition of HSV-2 was observed in 14 of the susceptible partners who received valacyclovir (1.9 percent), as compared with 27 (3.6 percent) who received placebo (hazard ratio, 0.52; 95 percent confidence interval, 0.27 to 0.99; P=0.04). HSV DNA was detected in samples of genital secretions on 2.9 percent of the days among the HSV-2-infected (source) partners who received valacyclovir, as compared with 10.8 percent of the days among those who received placebo (P<0.001). The mean rates of recurrence were 0.11 per month and 0.40 per month, respectively (P<0.001).

CONCLUSIONS

Once-daily suppressive therapy with valacyclovir significantly reduces the risk of transmission of genital herpes among heterosexual, HSV-2-discordant couples.

Seroprevalence and correlates of herpes simplex virus type 2 among urban Tanzanian women

BACKGROUND

Data on herpes simplex virus type 2 (HSV-2) among women in the general population of developing countries are limited.

GOALS

The goal of the study was to determine the seroprevalence of HSV-2 and to identify clinical, demographic, and behavioral correlates among women attending primary health care clinics.

STUDY DESIGN

This was a cross-sectional survey of 382 randomly chosen women aged 15 to 49 years.

RESULTS

The seroprevalence of HSV-2 was 39%. Only 2% had a history of genital herpes. HSV-2 was associated with antibody to HIV-1 (OR=2.3 [CI, 1.1-4.7]), syphilis (OR=4.7 [CI, 1.4-4.7]), and genital ulcers (OR=9.7 [CI 2.5-36.9]). Age, sexual debut, number of sex partners, and history of spontaneous abortion were found to be significantly associated with HSV-2. Eighty-two percent of the women with genital ulcers were HSV-2-seropositive, while syphilis accounted for 6% of cases. HSV-2 may thus be the most common cause of genital ulcers in this population.

CONCLUSION

In view of the high HSV-2 seroprevalence and its association with HIV-1 and genital ulcers, integration of HSV-2 therapeutic management in STD syndromic algorithms is recommended. Counseling on symptom recognition, asymptomatic shedding, and preventive measures is needed.

Herpes simplex virus type 2 infection among bar and hotel workers in northern Tanzania: prevalence and risk factors

BACKGROUND

Type-specific serological tests have allowed for a better understanding of the epidemiology of herpes simplex virus type 2 (HSV-2) infection in Africa.

GOAL

The goal was to determine risk factors for HSV-2 among bar and hotel workers in Moshi, Tanzania.

STUDY DESIGN

A cross-sectional study was conducted involving 515 workers in randomly selected bars and hotels in Moshi.

RESULTS

The seroprevalence of HSV-2 was 43.5%. Women were more likely to be HSV-2-seropositive than men (age-adjusted OR = 3.8; 95% CI = 2.5-5.8). In multivariate analyses, age was positively associated with HSV-2 in both women and men. HIV-1-seropositive women had a significantly increased risk of HSV-2 infection (adjusted OR = 2.8; 95% CI = 1.5-5.1). Other predictors of HSV-2 were religion and sexual behavior for women and level of education, frequency of alcohol use, and concurrent partners for men.

CONCLUSION

The most common genital infection was that with HSV-2. Control of HSV-2 might be an important strategy for HIV-1 infection prevention in this population.