A monoclonal blocking EIA for herpes simplex virus type 2 antibody: validation for seroepidemiological studies in Africa

Twenty years of herpes simplex virus type 2 (HSV-2) research in low-income and middle-income countries: systematic evaluation of progress made in addressing WHO prioritiesfor research in HSV-2 epidemiology and diagnostics

INTRODUCTION

Low-income and middle-income countries (LMICs) have a high burden of herpes simplex virus type 2 (HSV-2) infection, which has been strongly associated with HIV. In 2001, the WHO hosted a workshop to set research priorities for HSV-2 in LMICs. Periodic re-evaluation of research priorities is essential to ensure effective allocation of resources. This study describes the progress made between 2000 and 2020 in addressing the priorities identified in two of the five thematic areas that were the workshop's focus: HSV-2 epidemiology and diagnostics. The remaining areas are addressed in a companion paper.

METHODS

A systematic search of MEDLINE, CINAHL, Global Health and Cochrane databases was carried out. Relevant primary and secondary research studies conducted in LMICs, written in English and published from 2000-2020 were included. Two independent researchers screened, identified papers and extracted preidentified variables from study texts. Data were organised into an Excel spreadsheet and analysed using IBM SPSS V.26.

RESULTS

Overall, 4445 discrete papers were identified, of which 165 publications were eligible for inclusion. The highest general population HSV-2 prevalence was reported in South and West Africa. Prevalence was higher among women than men and increased with age. HSV-2 prevalence studies among key populations were few, and the majority were in East and South Asia. Cohort studies of HSV-2 incidence among younger populations (mean age=25 years) and HSV-2 infection prevalence in North Africa and the Middle East were few. The most researched topic in HSV-2 diagnostics addressed serological techniques and direct molecular biology. Studies of point-of-care testing were also few.

CONCLUSION

HSV-2 research identified in LMICs has mainly addressed the epidemiology and diagnostics priorities identified by the 2001 WHO workshop. Unaddressed priorities include point-of-care testing, antiviral resistance and exploration of HSV-2 epidemiology in neglected geographical settings and population subgroups.

Computational and Theoretical Analysis of the Association Between Gender and HSV-2 Treatment Adherence

Herpes simplex virus type 2 (HSV-2) is the most prevalent sexually transmitted infection in the world, despite the availability of effective anti-viral treatments. A mathematical model to explore the association between gender and HSV-2 treatment adherence is developed. Threshold parameters are determined and stabilities analyzed. Sensitivity analysis of the reproduction number and the numerical simulations suggest that treatment adherence for both females and males are equally important in keeping the reproduction as low as possible. The basic model is then extended to incorporate time-dependent intervention strategies. The Pontryagin's Maximum Principle is used to characterize the optimal level of the controls, and the resulting optimality system is solved numerically.

2017 European guidelines for the management of genital herpes

Genital herpes is one of the commonest sexually transmitted infections worldwide. Using the best available evidence, this guideline recommends strategies for diagnosis, management, and follow-up of the condition as well as for minimising transmission. Early recognition and initiation of therapy is key and may reduce the duration of illness or avoid hospitalisation with complications, including urinary retention, meningism, or severe systemic illness. The guideline covers a range of common clinical scenarios, such as recurrent genital herpes, infection during pregnancy, and co-infection with human immunodeficiency virus.

Evaluation of the HerpeSelect Express rapid test in the detection of herpes simplex virus type 2 antibodies in patients with genital ulcer disease

BACKGROUND

A rapid point-of-care test with high sensitivity and specificity is required in order to fulfill the need for early detection and screening of Herpes simplex virus type 2 (HSV-2) infection among patients with genital ulcer disease (GUD), for better management and control of virus transmission.

METHODS

The goal of this study is to evaluate the performance of the commercially available HerpeSelect Express rapid test in comparison with three ELISA assays: HerpeSelect ELISA, Kalon HSV-2 glycoprotein G2 assay, and monoclonal antibody blocking enzyme immunoassay, which was used as the gold standard for the detection of HSV-2 antibodies.

RESULTS

This study showed high sensitivity (ranging from 82.6 to 100%) and specificity (100%) of the HerpeSelect Express rapid test when compared to the three ELISA assays. The agreement between the HerpeSelect Express rapid test with the three ELISAs ranged from 93.3 to 100%.

CONCLUSION

The HerpeSelect Express rapid test has adequate sensitivity and specificity for confirming HSV-2 infection in patients with GUD, indicating its suitability for epidemiological studies.

European guideline for the management of genital herpes, 2010

This is the guideline for genital herpes simplex virus (HSV) management for the IUSTI/WHO Europe, 2010. They describe the epidemiology, diagnosis, clinical features, treatment and prevention of genital HSV infection. They include details on the management of HSV in pregnancy, those who are immunocompromised and the clinical investigation and management of suspected HSV-resistant disease.

Do herpes e suas implicações audiológicas: uma revisao de literatura

TEMA: herpes e audiologia. OBJETIVO: realizar revisão teórica principalmente sobre os vírus herpes simples tipo 1, herpes simples tipo 2 e varicela-zoster, bem como sobre seus efeitos na audição humana. Esses se constituem nos tipos de vírus herpéticos humanos de maior relevância para a área da Audiologia dentro da ciência da Fonoaudiologia e, no entanto, são pouco conhecidos e estudados, especialmente no Brasil. MÉTODOS: realizou-se pesquisa em bases de dados eletrônicas nacionais e internacionais, incluindo SciELO, MEDLINE e LILACS, a partir da seguinte combinação de descritores: herpes simplex/zoster X hearing loss ou deafness. Foram selecionados estudos publicados desde a década de 90 até os dias atuais, relevando-se aqueles que contivessem maior valor informativo, contribuindo para os objetivos do presente trabalho. CONCLUSÃO: os vírus herpéticos estudados apresentam estreita relação com distúrbios auditivos, independentemente da idade em que o sujeito é acometido.

Performance of the HerpeSelect (Focus) and Kalon enzyme-linked immunosorbent assays for detection of antibodies against herpes simplex virus type 2 by use of monoclonal antibody-blocking enzyme immunoassay and clinicovirological reference standards in Brazil

A total of 586 serum samples were used to evaluate the performance of type-specific herpes simplex virus type 2 (HSV-2) commercial enzyme-linked immunosorbent assays (ELISAs) by using the monoclonal antibody-blocking enzyme immunoassay (MAb-EIA) and a clinicovirological panel as reference standards. The Kalon and HerpeSelect ELISAs had similar sensitivities (93.5% and 93.8% compared with the results obtained by MAb-EIA, respectively, and 100% for both ELISAs compared with the results obtained with a clinicovirological panel). The Kalon ELISA had a higher specificity (96.5% and 96.8% compared with the results obtained by MAb-EIA and with a clinicovirological panel, respectively) than the HerpeSelect ELISA (86.9% and 94% compared with the results obtained by MAb-EIA and with a clinicovirological panel, respectively). A higher cutoff significantly improved the specificity of the HerpeSelect ELISA.

Seroprevalence of herpes simplex virus type 2 in multiple sclerosis

BACKGROUND

It has been proposed that multiple sclerosis (MS) might be a sexually transmitted disorder. There is evidence that seropositivity to herpes simplex virus type 2 (HSV-2) correlates well with the number of sexual partners. Accordingly, a raised overall HSV-2 seroprevalence in MS would lend support to this theory.

MATERIALS AND METHODS

Serum from 497 UK subjects with clinically definite MS was tested for antibodies to HSV-2 and compared with matched historical controls from within and outside London, blood donors and genito-urinary medicine (GUM) clinics.

RESULTS

The unadjusted MS seropositivity rate was 14%. HSV-2 seroprevalence in MS patients aged 35-64 years was significantly higher overall compared with a non-London general population in an unadjusted comparison. HSV-2 seroprevalence in London MS patients compared with London blood donors was significantly greater irrespective of age, but the MS seropositive rate was lower than GUM clinic attenders. In a logistic regression analysis, increased age, female sex and MS diagnosis all independently increased the odds of seropositivity after adjustment for each other.

CONCLUSION

It is concluded that there is increased likelihood of HSV-2 exposure in patients with MS and this may indicate a higher than average number of partners.

Development and evaluation of Varicella zoster virus ELISA for oral fluid suitable for epidemiological studies

An enzyme-linked immunosorbent assay (ELISA) for detection of Varicella zoster virus (VZV) antibodies in oral fluid is described. The assay was optimised and evaluated using paired serum and oral fluid from healthy adult volunteers (n = 205) and preschool children (n = 98), oral fluid samples collected for routine measles, mumps and rubella testing (n = 537) and samples from a study of atopic dermatitis (n = 252). As chickenpox is predominantly a childhood disease and most adults are immune, it was crucial to have samples from children aged 1-5 years to evaluate the assay. Mixture modelling of the oral fluid results was used to determine the optimum cut-off, sensitivity and specificity of the assay. Compared to paired sera tested by the same ELISA the sensitivity of the oral fluid assay was 93% and specificity 95.7% overall, varying slightly with age group. The assay was shown to have good potential for use in large-scale epidemiological studies.

National survey of diagnostic services for genital herpes

OBJECTIVE

To investigate the provision of diagnostic services for genital herpes simplex virus (HSV) infection in the United Kingdom.

METHODS

National survey of laboratories providing diagnostic services for genital herpes.

RESULTS

Completed questionnaires were returned from 25/32 (78%) laboratories participating in the Clinical Virology Network, including seven in London, 12 in the rest of England, one in Wales, four in Scotland, and one in Northern Ireland. Virus culture was the diagnostic method of choice in 20/25 (80%) laboratories; 5/25 (20%) routinely used HSV DNA detection by polymerase chain reaction (PCR). HSV PCR for DNA detection in cerebrospinal fluid (CSF) was available in 17/25 (68%) laboratories. Typing of isolates (HSV-1 or HSV-2) was performed routinely in 22/25 (88%) laboratories. Only 2/25 (8%) laboratories offered HSV type specific serology, although an additional 12/25 (48%) referred requests elsewhere. Consistent with this finding, the number of HSV type specific antibody tests referred to the Health Protection Agency increased by nearly fivefold between 1997 and 2003.

CONCLUSIONS

Virus culture remains the preferred diagnostic method for genital herpes, despite evidence indicating that its sensitivity is suboptimal compared to PCR. As HSV PCR is widely available for testing of CSF, it is recommended that clinicians and virologists discuss ways to implement PCR testing of genital swabs, thus enabling greater diagnostic accuracy. A call is made for studies to assess the use of HSV type specific serology in genitourinary medicine (GUM) settings, now that rapid and validated assays have become available and guidelines have been issues to provide recommendations on their use.

Seroprevalence of herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2) in former East and West Germany, 1997-1998

The aim of this study was to investigate the seroprevalence of herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2) in representative samples of the total former East German (FEG) and total former West German (FWG) populations. Type-specific testing with the HSV-1 (gG1) and HSV-2 (gG2) indirect ELISA was performed on an age- and sex-stratified random subsample of 3,792 sera collected during the 1997-1998 German National Health Survey. Weighted seroprevalence estimates were calculated for the total FEG and FWG populations. The overall age-standardised seroprevalence of HSV-1 was 82.6% in Germany, 85.5% (95%CI, 83.4-87.3%) in FEG and 81.8% (95%CI, 79.9-83.6%) in FWG. The overall seroprevalence of HSV-2 was 13.3% (95%CI, 11.8-14.9) in Germany, 16.5% (95%CI, 14.1-18.9) in FEG and 12.6% (95%CI, 10.7-14.5%) in FWG. The difference between FEG and FWG was largely due to the significantly higher age-adjusted seroprevalence of HSV-1 and HSV-2 in women (but not men) in FEG as compared to FWG. The HSV seroprevalence estimates in this study are consistent with results of previous less representative seroprevalence studies in Germany. Differences in HSV-2 seroprevalence between FEG and FWG suggest differences in sexual behaviour that warrant further investigation.

The seroepidemiology of herpes simplex virus type 1 and 2 in Europe

OBJECTIVES

To describe the seroepidemiology of herpes simplex virus (HSV) types 1 and 2 in the general populations of eight European countries to better understand recent reported changes in disease epidemiology.

METHODS

Belgium, Bulgaria, Czech Republic, England and Wales, Finland, Germany, Netherlands, and Slovenia conducted national cross sectional serological surveys for HSV-1 and HSV-2 between 1989 and 2000. Survey sizes ranged from 3000 to 7166 sera. External quality control was ensured through reference panel testing.

RESULTS

Large intercountry and intracountry differences in HSV-1 and HSV-2 seroprevalence were observed. Age standardised HSV-1 seroprevalence ranged from 52% in Finland, to 57% in the Netherlands, 67% in Belgium, 81% in Czech Republic, and 84% in Bulgaria. Age standardised (>12 years) HSV-2 seroprevalence ranged from 24% in Bulgaria, to 14% in Germany, 13% in Finland, 11% in Belgium, 9% in Netherlands, 6% in Czech Republic, and 4% in England and Wales. In all countries, probability of seropositivity for both infections increased with age. A large proportion of teenagers and young adults remain HSV-1 susceptible particularly in northern Europe. Women were significantly more likely to be HSV-2 seropositive in six of seven (p<0.05) countries and HSV-1 seropositive in four of seven (p<0.05) countries, particularly in northern Europe. No significant evidence of a protective role of HSV-1 for HSV-2 infection was found adjusting for age and sex (p<0.05).

CONCLUSIONS

There is large variation in the seroepidemiology of HSV-1 and HSV-2 across Europe. The observation that a significant proportion of adolescents are now HSV-1 susceptible may have implications for transmission and clinical presentation of HSV-1 and HSV-2.

New estimates of herpes simplex virus type 2 seroprevalence in England: 'high' but stable seroprevalence over the last decade

OBJECTIVES

There have been few recent population-based herpes simplex virus type 2 (HSV-2) seroprevalence studies in England, but reports from the United States have indicated a 30% rise in HSV-2 seroprevalence between 1976 and 1994. This study aimed to ascertain trends in HSV-2 infection in England between 1991 and 2000.

STUDY DESIGN

Anonymized serum residues collected through public health laboratories across England from individuals aged 16 to 64 years seeking health care through the National Health Service in 1991 (n = 2259) and 2000 (n = 3646) were tested for anti-HSV-2 IgG using the HerpeSelect 2 enzyme-linked immunosorbent assay IgG (Focus).

RESULTS

In 9 sites across England, the age- and sex-standardized HSV-2 seroprevalence was 9.7% (95% confidence interval, 8.4-11.0%). Data from 4 sites common to both study years indicated no change in HSV-2 seroprevalence between 1991 and 2000.

CONCLUSIONS

After adjustment for age, sex, and geographic location, there was no evidence of a change in seroprevalence between 1991 and 2000.

Performance and use of a ribonucleotide reductase herpes simplex virus type-specific serological assay

In response to the increasingly evident need for herpes simplex virus (HSV) serotype-specific serologic assays that rely on proteins other than glycoprotein-G (gG), we developed a rapid serologic assay that is based on type-specific epitopes within the large subunit of HSV ribonucleotide reductase (R1). The assay (Au-2 enzyme-linked immunosorbent assay [ELISA]) uses an HSV type 2 (HSV-2) R1 peptide antigen. It provides a reliable method for detecting serotype-specific antibody to a protein other than gG-2. The Au-2 ELISA has high sensitivity and specificity as determined by direct comparison to Western blotting, a widely accepted "gold standard," and to ELISA with an HSV-1 R1 peptide (Au-1). The use of the Au-2 ELISA in conjunction with the gG-2-based assays will improve the sensitivity and specificity of serologic diagnosis and patient management.

Seroepidemiological study of herpes simplex virus types 1 and 2 in Brazil, Estonia, India, Morocco, and Sri Lanka

BACKGROUND

The association between herpes simplex virus type 2 (HSV-2) and human immunodeficiency virus (HIV) and the development of HSV vaccines have increased interest in the study of HSV epidemiology.

OBJECTIVES

To estimate the age and sex specific seroprevalence of HSV-1 and HSV-2 infections in selected populations in Brazil, Estonia, India, Morocco, and Sri Lanka.

METHODS

Serum samples were collected from various populations including children, antenatal clinic attenders, blood donors, hospital inpatients, and HIV sentinel surveillance groups. STD clinic attenders were enrolled in Sri Lanka, male military personnel in Morocco. Sera were tested using a common algorithm by type specific HSV-1 and HSV-2 antibody assay.

RESULTS

13,986 samples were tested, 45.0% from adult females, 32.7% from adult males, and 22.3% from children. The prevalence of HSV-1 varied by site ranging from 78.5%-93.6% in adult males and from 75.5%-97.8% in adult females. In all countries HSV-1 seroprevalence increased significantly with age (p<0.001) in both men and women. The prevalence of HSV-2 infection varied between sites. Brazil had the highest age specific rates of infection for both men and women, followed by Sri Lanka for men and Estonia for women, the lowest rates being found in Estonia for men and India for women. In all countries, HSV-2 seroprevalence increased significantly with age (p<0.01) and adult females had higher rates of infection than adult males by age of infection.

CONCLUSIONS

HSV-1 and HSV-2 seroprevalence was consistently higher in women than men, particularly for HSV-2. Population based data on HSV-1 and HSV-2 will be useful for designing potential HSV-2 vaccination strategies and for focusing prevention efforts for HSV-1 and HSV-2 infection.

Comparison of washing and swabbing procedures for collecting genital fluids to assess cervicovaginal shedding of herpes simplex virus type 2 DNA

Asymptomatic genital shedding of herpes simplex virus type 2 (HSV-2) DNA was evidenced by real-time PCR in 25 (13.2%) of 188 cervicovaginal lavage samples and in only 13 (6.9%) paired cervicovaginal samples from 188 HSV-2-seropositive, nonpregnant childbearing-aged human immunodeficiency virus-seronegative women living in Gabon. These observations demonstrate that cervicovaginal washing is more suitable than endocervicovaginal swabbing for detecting and quantifying HSV-2 DNA by PCR in female genital secretions.

Cervicovaginal neutralizing antibodies to herpes simplex virus (HSV) in women seropositive for HSV Types 1 and 2

Antibodies to herpes simplex virus type 1 (HSV-1) and HSV-2 of the immunoglobulin G (IgG) and IgA isotypes were detected in the cervicovaginal secretions (CVS) of 77 HSV-1- and HSV-2-seropositive but clinically asymptomatic African women by type-specific enhanced chemiluminescence Western blotting (ECL-WB). Of the 77 subjects, 34 were HIV negative, shedding HSV-2 DNA in their genital secretions; 20 were HIV positive, shedding HSV-2 DNA; and 23 were HIV negative, not shedding HSV-2 DNA. HSV-specific IgG was detected in CVS of nearly 70% of the women studied. HSV-specific IgA was found in CVS of 50% of the women studied. The distribution of CVS HSV-specific antibodies to each HSV type was highly heterogeneous, with a slight predominance of detectable IgG to HSV-1 (59%) over IgG to HSV-2 (41%), whereas the frequency of detectable IgA to HSV-1 (39%) was similar to that of IgA to HSV-2 (36%). The presence of detectable HSV-specific antibodies was inversely associated with HSV-2 DNA genital asymptomatic shedding but was not affected by HIV seropositivity. In addition, 13 of 77 (17%) CVS samples showed neutralizing activity against HSV-2, as assessed by an HSV-2 in vitro infectivity reduction assay. Neutralizing activity in CVS was associated with the presence of IgG and/or IgA antibodies to HSV-1 and/or to HSV-2 by ECL-WB. Among women whose CVS showed HSV-2-neutralizing activity, the specific activity of HSV-specific neutralizing antibodies was substantially (fivefold) higher in HSV-2 DNA shedders than in nonshedders. In conclusion, HSV-specific antibodies are frequently detected in CVS of asymptomatic African women seropositive for HSV-1 and HSV-2. A subset of these women had functional neutralizing activity against HSV-2 in their CVS. The origin of these antibodies and their role in HSV-2 disease of the female genital tract remain to be determined.

Comparison of STD prevalences in the Mwanza, Rakai, and Masaka trial populations: the role of selection bias and diagnostic errors

OBJECTIVES

To assess bias in estimates of STD prevalence in population based surveys resulting from diagnostic error and selection bias. To evaluate the effects of such biases on STD prevalence estimates from three community randomised trials of STD treatment for HIV prevention in Masaka and Rakai, Uganda and Mwanza, Tanzania.

METHODS

Age and sex stratified prevalences of gonorrhoea, chlamydia, syphilis, HSV-2 infection, and trichomoniasis observed at baseline in the three trials were adjusted for sensitivity and specificity of diagnostic tests and for sample selection criteria.

RESULTS

STD prevalences were underestimated in all three populations because of diagnostic errors and selection bias. After adjustment, gonorrhoea prevalence was higher in men and women in Mwanza (2.8% and 2.3%) compared to Rakai (1.1% and 1.9%) and Masaka (0.9% and 1.8%). Chlamydia prevalence was higher in women in Mwanza (13.0%) compared to Rakai (3.2%) and Masaka (1.6%) but similar in men (2.3% in Mwanza, 2.7% in Rakai, and 2.2% in Masaka). Prevalence of trichomoniasis was higher in women in Mwanza compared to women in Rakai (41.9% versus 30.8%). Herpes simplex virus type 2 (HSV-2) seroprevalence and prevalence of serological syphilis (TPHA+/RPR+) were similar in the three populations but the prevalence of high titre syphilis (TPHA+/RPR >/=1:8) in men and women was higher in Mwanza (5.6% and 6.3%) than in Rakai (2.3% and 1.4%) and Masaka (1.2% and 0.7%).

CONCLUSIONS

Limited sensitivity of diagnostic and screening tests led to underestimation of STD prevalence in all three trials but especially in Mwanza. Adjusted prevalences of curable STD were higher in Mwanza than in Rakai and Masaka.

Syndromic management of sexually-transmitted infections and behaviour change interventions on transmission of HIV-1 in rural Uganda: a community randomised trial

BACKGROUND

Treatment of sexually-transmitted infections (STIs) and behavioural interventions are the main methods to prevent HIV in developing countries. We aimed to assess the effect of these interventions on incidence of HIV-1 and other sexually-transmitted infections.

METHODS

We randomly allocated all adults living in 18 communities in rural Uganda to receive behavioural interventions alone (group A), behavioural and STI interventions (group B), or routine government health services and community development activities (group C). The primary outcome was HIV-1 incidence. Secondary outcomes were incidence of herpes simplex virus type 2 (HSV2) and active syphilis and prevalence of gonorrhoea, chlamydia, reported genital ulcers, reported genital discharge, and markers of behavioural change. Analysis was per protocol.

FINDINGS

Compared with group C, the incidence rate ratio of HIV-1 was 0.94 (0.60-1.45, p=0.72) in group A and 1.00 (0.63-1.58, p=0.98) in group B, and the prevalence ratio of use of condoms with last casual partner was 1.12 (95% CI 0.99-1.25) in group A and 1.27 (1.02-1.56) in group B. Incidence of HSV2 was lower in group A than in group C (incidence rate ratio 0.65, 0.53-0.80) and incidence of active syphilis for high rapid plasma reagent test titre and prevalence of gonorrhoea were both lower in group B than in group C (active syphilis incidence rate ratio, 0.52, 0.27-0.98; gonorrhoea prevalence ratio, 0.25, 0.10-0.64).

INTERPRETATION

The interventions we used were insufficient to reduce HIV-1 incidence in rural Uganda, where secular changes are occurring. More effective STI and behavioural interventions need to be developed for HIV control in mature epidemics.

Herpes simplex 2 risk among women in a polygynous setting in rural West Africa

OBJECTIVES

To determine risk factors for herpes simplex 2 (HSV2) infection in women in a polygynous rural Gambian population.

METHODS

Data from women who participated in a cross-sectional survey of reproductive health were matched to their own and, for women who had been or were married (ever-married), their spouses' data collected in a cross-sectional survey of fertility interests, including information on marital histories.

RESULTS

Data were available on 150 never-married and 525 ever-married women. HSV2 prevalence was 16% amongst never-married women and 36% amongst ever-married women. For ever-married women, their own personal characteristics (age, ethnicity and genital cutting status) and events from their husbands' marriage history were important determinants of HSV2 infection. Women whose husbands married for the first time over age 35 were at greater risk than women whose husbands married by age 24 [odds ratio (OR) 2.72, 95% confidence interval (CI) 1.20-6.10]. Women whose husband reported interest in a new marriage were more likely to be HSV2 positive (OR 1.91, 95% CI 1.18-3.09). Women whose husbands were currently monogamous but had had previous marriages (OR 2.76, 95% CI 1.30-5.88) and women in currently polygynous marriages (OR 2.88, 95% CI 1.66-5.01) were three times as likely to be HSV2 positive as women who were their husband's only wife ever.

CONCLUSION

Much transmission of HSV2 in this setting occurs within marriage where opportunity for personal protection is limited. High levels of transmission within marriage may undermine the impact of sexual behaviour change programmes aiming to reduce HSV2 and HIV incidence and complicate their evaluation.

A community randomized controlled trial to investigate impact of improved STD management and behavioural interventions on HIV incidence in rural Masaka, Uganda: trial design, methods and baseline findings

OBJECTIVE

To describe study design, methods and baseline findings of a behavioural intervention alone and in combination with improved management of sexually transmitted diseases (STDs) aimed at reducing HIV incidence and other STDs.

DESIGN

A three-arm community randomized controlled trial (RCT) of 18 rural communities (approximately 96 000 adults) in SW Uganda. A standardized behavioural intervention was implemented in 12 communities (arms A and B) through community-based education, meetings and information leaflets. Six of these communities in addition received improved STD management through government and private health units (arm B). Arm C communities received routine government health services. Impact assessment was through three questionnaire and serological surveys of 750-1000 adults in each community at 18-24-month intervals. The primary outcome measure was HIV incidence and secondary measures were syphilis and herpes simplex virus type 2 incidence, prevalence of Neisseria gonorrhoea and Chlamydia trachomatis and sexual behaviour changes.

RESULTS

Approximately 15 000 adults (72% of eligible population) were enrolled at baseline. HIV baseline prevalence rates were 9-10% in all arms and demographic and behavioural characteristics and STD prevalence were also similar. In intervention communities, there were 391 995 attendance at 81 502 activities (6.1 per target adult), 164 063 leaflets distributed (2.6 per person) and 1 586 270 condoms (16.5 condoms per adult). In the STD communities a total of 12 239 STD cases (65% women) were seen over a 5-year period (7.7 per 100 adults/year).

CONCLUSION

This is the first community RCT of its type with a behavioural component. There is fair baseline comparability between study arms and process data suggest that interventions were adequately implemented.

Serological testing for herpes simplex virus (HSV)-1 and HSV-2 infection

Serological tests for herpes simplex virus (HSV) that can accurately distinguish between HSV-1 and HSV-2 are now commercially available. These tests detect antibodies to HSV glycoproteins G-1 and G-2, which evoke a type-specific antibody response. Focus Technologies produces the HerpeSelect-1 and HerpeSelect-2 enzyme-linked immunosorbent assay tests and the HSV-1 and HSV-2 HerpeSelect1/2 Immunoblot. Diagnology has marketed POCkit-HSV-2, a point-of-care test for HSV-2 that allows blood from a finger stick to be tested in a clinic. These tests can be used to confirm a genital herpes diagnosis, establish diagnosis of HSV infection in patients with atypical complaints, identify asymptomatic carriers, and identify persons at risk for acquiring HSV. Potential settings for use of these tests include sexually transmitted disease clinics, prenatal clinics, and clinics that care for patients with human immunodeficiency virus. Patient interest in HSV serological tests appears high.

Challenges in genital herpes simplex virus management

Development of serologic assays to detect antibodies to herpes simplex virus (HSV) glycoproteins (g)G1 and (g)G2 has allowed accurate definition of the seroprevalence of HSV-2 worldwide. Studies from all continents indicate epidemic proportions of HSV-2 infection. In the United States, 1 in 5 sexually active adults is infected. In Africa and the Caribbean, HSV prevalence is higher. Since the development of the acyclic nucleoside derivatives acyclovir, famciclovir, and valacyclovir, treatment of mucocutaneous HSV is a practice of everyday medical care. Yet, despite effective drugs, there is widespread discontent by clients and providers about care of patients with genital herpes. Much of this relates to transmission complexities and the varied natural history of the infection. However, over time, most patients adjust to their disease and the medical and psychosocial complications. Recent studies show condoms reduce transmission, providing an important tool for counseling the patient with newly diagnosed genital herpes.

Use of a fragment of glycoprotein G-2 produced in the baculovirus expression system for detecting herpes simplex virus type 2-specific antibodies

Fragments of glycoprotein G (gG-2(281-594His)), comprising residues 281 to 594 of herpes simplex virus type 2 (HSV-2), glycoprotein G of HSV-1 (gG-1(t26-189His)), and glycoprotein D of HSV-1 (gD-1(1-313)), were expressed in the baculovirus expression system to develop an assay for the detection of HSV-1 and HSV-2 type-specific antibodies. The expression of the gG-1(t26-189His) and gG-2(281-594His) fragments was analyzed by Western blotting using monoclonal antibodies LP10 and AP1, respectively. The molecular masses of the major products of gG-1(t26-189His) and the fragment of gG-2(281-594His) were 36 to 39 kDa and 64 to 72 kDa, respectively. Human sera positive for HSV-1 reacted with gG-1(t26-189His), sera positive for HSV-2 reacted with the gG-2(281-594His) fragment, and sera positive for both types reacted with gG-1(t26-189His) and gG-2(281-594His) in Western blotting. The human sera recognized polypeptides of gG-2(281-594His) with molecular masses of 57 to 67 and 120 to 150 kDa and additional faint bands of 21, 29, and 45 kDa. The recombinant gG-1(t26-189His) and the recombinant gG-2(281-594His) fragment were used as type-specific antigens for the detection of HSV-1- and HSV-2-specific antibody responses in human sera, respectively. As type-common antigens, an extract of HSV-1-infected Vero cells and recombinant gD-1(1-313) were used. An enzyme-linked immunosorbent assay to detect type-specific antibodies was developed, and the sensitivity and specificity were evaluated by comparison with commercial tests by using sera obtained from different sources. The sensitivity and specificity were 91.5 and 95.5%, respectively, compared to the Gull assay. The gG-2(281-594His) fragment can be obtained in relatively large quantities at low cost.

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.

Comparison of a monoclonal antibody-blocking enzyme-linked immunoassay and a strip immunoblot assay for identifying type-specific herpes simplex virus type 2 serological responses

Detection of herpes simplex virus type 2 (HSV-2)-specific antibodies by a monoclonal antibody (MAb)-blocking enzyme-linked immunoassay (EIA) was compared with detection by a strip immunoblot assay (SIA) in a sexually transmitted disease (STD) clinic population. The study population consisted of 1,683 genitourinary medicine clinic attendees (582 women and 1,101 men). Sera were tested for the presence of HSV-2 antibody by use of the blocking EIA, in which binding of the MAb AP-1 to HSV-2 glycoprotein G-2 (gG-2) is blocked by HSV-2-specific antibody. The Chiron RIBA HSV-1 and -2 strip immunoassay (SIA) utilizes HSV-1- and HSV-2-specific or cross-reactive antigens immobilized on nitrocellulose strips (HSV gB-1 and HSV gG-1 peptide bands specific for HSV-1 antibody, HSV-2 gG-2 band specific for HSV-2 antibody, and HSV gD-2 band cross-reactive for HSV-1 and HSV-2 antibodies). A total of 1,612 sera were tested by MAb-blocking EIA for HSV-2 antibody and by SIA for HSV-1 and HSV-2 antibodies. By EIA, 541 (33.6%) sera were positive for HSV-2 antibody and 1,068 sera were negative for HSV-2 antibody; 3 sera gave equivocal results. HSV-2 antibody was detected in 555 (34.4%) sera by SIA; 144 (26%) of these sera possessed only HSV-2 antibody, and 411 (74%) sera contained both HSV-1 and HSV-2 antibodies. SIA detected HSV-1 antibody in 1,155 (71.6%) sera; 744 (64%) of these sera contained HSV-1 antibody alone. Sixteen sera contained antibody against HSV but could not be typed by SIA. A total of 512 sera were positive for HSV-2 antibody by both the EIA and SIA. We concluded that the blocking EIA and SIA showed a high level of agreement in detecting HSV-2 antibody in this population. In contrast to the SIA, the blocking EIA is a useful tool for large epidemiological studies, though the SIA proved to be slightly more sensitive once sera with discrepant results were further tested.