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

Role of Herd Immunity in Determining the Effect of Vaccines against Sexually Transmitted Disease

BACKGROUND

Vaccination programs provide both direct protection to those immunized and herd immunity, which is indirect protection of those who remain susceptible, owing to a reduced prevalence of infections.

METHODS

The well-understood impact of vaccination against ubiquitous childhood infections is compared with that of vaccination against sexually transmitted infections (STIs), and theoretical insights are derived from a review of mathematical modeling studies.

RESULTS

Typically, a large fraction of cases of STIs are acquired by those with modest risk, and these cases could be prevented by low-efficacy vaccines. If coverage is good, vaccination of only one sex can protect the other sex. Candidate vaccines against human papillomavirus (HPV) and genital herpes are in the final stages of testing. The former is likely to be highly efficacious for a limited number of disease-causing HPV types, and the latter has provided protection against disease in women who initially were seronegative for both herpes simplex virus (HSV) type 1 and HSV-2, with 73% efficacy. In models, this vaccine had a substantial impact when infectiousness was assumed to be reduced along with incidence of disease.

CONCLUSION

With such vaccines on the horizon, the requirements for vaccine delivery need to be considered, particularly who should be vaccinated and at what age.

Recent trends in the epidemiology of sexually transmitted infections in the European Union

Sexually transmitted infections (STIs) are a major public health problem in Europe. We review recent trends in the epidemiology of the major acute STIs in the European Union and Norway, their key determinants, and opportunities for enhancing STI prevention interventions in the region.

Ethics of screening for asymptomatic herpes virus type 2 infection

Commercial tests for herpes simplex virus are now widely available, and some experts have advocated screening. But can screening be ethical when false positive results occur, many infected people are asymptomatic, and no cure is available?

Performance of focus ELISA tests for herpes simplex virus type 1 (HSV-1) and HSV-2 antibodies among women in ten diverse geographical locations

To determine the sensitivity and specificity of Focus HerpeSelect ELISAs, sera or plasma samples from women aged 18-55 years were collected in ten cities from eight countries and tested by HerpeSelect HSV-1 ELISA (Focus-HSV-1) and by HerpeSelect HSV-2 ELISA (Focus-HSV-2). Sera with Focus-HSV-2-positive results were retested; 94% of the 3617 samples retested were positive. A subset of sera from each site was then selected, based on the HSV-2 results, and tested by Western blot (WB). The sensitivity and specificity were determined with samples from ten sites (n = 967) for Focus-HSV-1 and from seven sites (n = 675) for Focus-HSV-2. Focus-HSV-1 and WB results were concordant (both negative or both positive) for 97% of samples, with 99% sensitivity and 77% specificity. Specimens from Songkla, Thailand had 84% concordance with WB results for HSV-1, while three other sites had 100% concordance. Concordance of Focus-HSV-2 and WB was 92%, with 97% sensitivity and 89% specificity. Ibadan, Nigeria had 78% concordance. Focus-HSV-2 sensitivity and specificity in sites other than Ibadan were 97% and 93%, respectively. Raising the positive cut-off index value for HSV-2 from 1.1 to 3.5 yielded a sensitivity of 90% and a specificity of 96%. A sensitivity of 90% and a specificity of 98% were achieved for sites other than Nigeria with the higher cut-off. In summary, the sensitivity and specificity of the Focus-HSV-1 and Focus-HSV-2 tests varied by site. Performance data generated in one area may not be applicable to other populations.

Patient satisfaction with care for genital herpes: insights from a global survey

OBJECTIVE

To describe patient experiences and views regarding genital herpes management.

METHODS

Between February 2002 and January 2003, subjects with genital herpes were recruited via the International Herpes Alliance website and through banners on additional sites. Surveys were available in English, French, Spanish, Italian, and German and assessed views on access to care, diagnosis, related emotional experiences, educational resources, counselling, pharmacotherapy, and satisfaction with care.

RESULTS

2075 patient responses from 78 countries were analysed. 49% reported their diagnosis was by culture (or other direct detection) and 9% by antibody test, while 34% reported they had been diagnosed by examination alone. 65% used a prescription antiviral therapy, 18% a topical antiviral therapy, and 17% an alternative therapy. Of 901 subjects who reported on frequency of antiviral use, only 30% reported a frequency consistent with a suppressive regimen while 59% of respondents said they would be likely to take daily therapy if it reduced the frequency of outbreaks. Patient satisfaction with management of physical symptoms was independently associated with duration of initial visit >or=15 minutes (adjusted odds ratio (OR) = 4.52), receiving a prescription (adj OR = 2.34) and receipt of a brochure/fact sheet (adj OR = 2.14). Satisfaction with attention to emotional issues also correlated with the first two of these factors.

CONCLUSIONS

Genital herpes management may be improved by including the use of confirmatory laboratory testing, employing a full range of antiviral therapy options, providing educational materials, and committing more time to counselling at the initial visit.

Performance of commercially available enzyme immunoassays for detection of antibodies against herpes simplex virus type 2 in African populations

Data are accumulating on the performance of enzyme immunoassays (EIAs) for the detection of herpes simplex virus type 2 (HSV-2) infection in North America and Europe, but little is known about their performance in other populations. Nine test kits were evaluated with 330 serum samples from sub-Saharan Africa. The tests were first compared to the monoclonal antibody (MAb) EIA (Central Public Health Laboratory, London, United Kingdom). Samples that gave discordant results in the MAb EIA and in the three tests that performed best compared to the MAb EIA were tested by Western blotting (University of Washington, Seattle). A random sample of concordant samples was also tested, and the sensitivities and specificities of the different tests were calculated, taking into account this sampling strategy. The sensitivities of the tests ranged from 86 to 100%; the specificities ranged from 47 to 99%. The tests that performed best were the Gull Premier EIA (sensitivity, 86.3%; specificity, 97.6%) and the Kalon Biological (sensitivity, 92.3%; specificity, 97.7%) and Biokit (sensitivity, 86.7%; specificity, 92.6%) tests. It cannot be assumed that enzyme immunoassays for the detection of HSV-2 infection that perform well in industrialized countries will perform equally well in other populations.

Seroepidemiology of Herpes Simplex Type 2 in Pregnant Women in Belgium

OBJECTIVE

The objective of this study was to study the prevalence of herpes simplex virus (HSV) type 2 in pregnant women in Belgium.

STUDY DESIGN

The serum of 1000 consecutive women was collected. HSV-1 and HSV-2 control sera were added to the study. HSV-2 antibodies were tested with the HerpeSelect 2 enzyme-linked immunosorbent assay (ELISA; Focus) based on the use of the recombinant gG-2 antigen.

RESULTS

The 21 HSV-2 control subjects were positive. Among the HSV-1 control subjects, 18 were negative and 4 were positive. Among the pregnant women, 80.3% were negative, 1.5% had equivocal results, and 18.2% were positive. No statistical difference was observed according to the origin (European or African) of the women.

CONCLUSIONS

The results obtained with the control sera indicate a high sensitivity of the Focus ELISA, as well as a capacity to discriminate between HSV-1/HSV-2 infection. The HSV-2 prevalence in the studied population raises the question of the possible benefit of a specific preventive program in pregnant women.

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.

Correlates of National HIV Seroprevalence

BACKGROUND

Ecologic analyses of social and developmental correlates of country-level HIV seroprevalence may suggest strategies for combating the HIV/AIDS epidemic.

METHODS

Regression analyses were performed for 81 variables obtained primarily from United Nation agencies for 122 developing countries. Variable measures were compared between highest and lowest tertiles of HIV seroprevalence.

RESULTS

Geography, religion, and income inequality were independently associated with HIV seroprevalence. Countries with earlier ages at first sex, higher teenage birth rates, and higher fertility rates had higher HIV seroprevalence. Countries with high HIV seroprevalence had fewer women using contraceptives, more persons with casual sex partners, and higher herpes simplex virus 2 seroprevalence. Male circumcision and Muslim religion were colinearly associated with lower HIV seroprevalence. Countries with high HIV seroprevalence had fewer doctors, more midwives, and less access to essential medications, but health spending differences were minor.

CONCLUSIONS

Ecologic analyses support population-level behavioral approaches, such as delaying sexual debut and discouraging casual sex partners, and reinforce biologic measures, such as controlling sexually transmitted infections and promoting male circumcision, for HIV prevention. Fewer births attended by skilled personnel, but more midwives, in countries with the highest HIV seroprevalence suggest potential strategies for reducing mother-to-child transmission. Correlations with selected health indicators suggest additional obstacles for implementing HIV treatment programs.

Infection with herpes simplex virus type 1 is associated with cognitive deficits in bipolar disorder

BACKGROUND

In a previous investigation, we found an association between reduced cognitive functioning and the prevalence of antibodies to herpes simplex virus type 1 in individuals with schizophrenia. The current study was undertaken to determine if this association also occurs in individuals with bipolar disorder.

METHODS

Cognitive functioning and serologic evidence of infection with potentially neurotropic herpesviruses were measured in 117 individuals with bipolar disorder and in 100 individuals without a history of psychiatric disorder. Cognitive functioning was evaluated with the Repeatable Battery for the Assessment of Neuropsychological Status. For each patient, serologic evidence of infection was ascertained by the measurement of serum immunoglobulin G class antibodies with specificities for six potentially neurotropic human herpesviruses. The association between serologic evidence of herpesvirus infection and cognitive functioning was analyzed by univariate analyses, as well as multivariate analyses that included demographic and clinical factors associated with cognitive functioning.

RESULTS

Serologic evidence of infection with herpes simplex virus type 1 was an independent predictor of decreased cognitive functioning in the individuals with bipolar disorder (F = 20.5, p <.0001). Discriminant function analysis indicated that most of the difference in cognitive functioning between individuals who were antibody positive and antibody negative for herpes simplex virus type 1 could be attributed to immediate verbal memory (F = 12.07, p <.001). There was no significant association between cognitive functioning and the other human herpesviruses. No association between antibodies to herpesviruses and cognitive functioning was found in the control individuals without a history of psychiatric disorder.

CONCLUSIONS

Serologic evidence of herpes simplex virus type 1 infection is associated with cognitive impairment in individuals with bipolar disorder.

Transmission of HIV-1 infection in sub-Saharan Africa and effect of elimination of unsafe injections

During the past year, a group has argued that unsafe injections are a major if not the main mode of HIV-1 transmission in sub-Saharan Africa. We review the main arguments used to question the epidemiological interpretations on the lead role of unsafe sex in HIV-1 transmission, and conclude there is no compelling evidence that unsafe injections are a predominant mode of HIV-1 transmission in sub-Saharan Africa. Conversely, though there is a clear need to eliminate all unsafe injections, epidemiological evidence indicates that sexual transmission continues to be by far the major mode of spread of HIV-1 in the region. Increased efforts are needed to reduce sexual transmission of HIV-1.

Evaluations of unformulated and formulated dendrimer-based microbicide candidates in mouse and guinea pig models of genital herpes

Prevention of sexually transmitted infections is a priority in developed and developing countries. One approach to prevention is the use of topical microbicides, and one promising approach is the use of dendrimers, highly branched macromolecules synthesized from a polyfunctional core. Three new dendrimer products developed to provide stable and cost-efficient microbicides were initially evaluated in vitro for anti-herpes simplex virus activity and then in vivo by using a mouse model of genital herpes. From these experiments one product, SPL7013, was chosen for further evaluation to define the dose and duration of protection. Unformulated SPL7013 provided significant protection from genital herpes disease and infection at concentrations as low as 1 mg/ml and for at least 1 h following topical (intravaginal) administration of 10 mg/ml. This compound was then formulated into three vehicles and further evaluated in mouse and guinea pig models of genital herpes infection. In the murine evaluations each of the formulations provided significant protection at concentrations of 10 and 50 mg/ml. Formulated compounds provided protection for at least 1 h at a concentration of 10 mg/ml. From these experiments formulation 2V was chosen for dose ranging experiments using the guinea pig model of genital herpes. The guinea pig evaluations suggested that doses of 30 to 50 mg/ml were required for optimal protection. From these studies a lead compound and formulation (2V of SPL7013) was chosen for ongoing evaluations in primate models of simian immunodeficiency virus and Chlamydia trachomatis infection.

Patient and physician partnerships in managing genital herpes

Genital herpes simplex virus infections are widespread throughout the world and are characterized by stigma, myth, and anxiety by patients and the public but are perceived as trivial by most physicians. Surveys in the United States, Europe, Australia, and South Africa have measured the unfavorable effect of genital herpes on infected patients, health care resources, and workplace productivity. These surveys identified limited satisfaction of patients with current care and support (41% satisfied), although satisfaction scores were greater for patients receiving suppressive antiviral therapy (56% satisfied). Bridging the gap between patients and physicians is vital for improving the management of genital herpes. Key to facilitating patient-physician partnerships is education and recognition by physicians that patients with genital herpes may have expert knowledge. In effective partnerships, physicians and patients can have informed constructive discussions such that patients share in the responsibility for managing their disease and in therapeutic decision making.

Clinical manifestations and treatment considerations of herpes simplex virus infection

Herpes simplex viruses (HSV) types 1 and 2 cause infections manifesting as dermatologic, immunologic, and neurologic disorders. Some of the most important manifestations and complications of HSV infection are considered here in a neuroanatomic context. This discussion should aid in understanding the pathogenesis and, in some cases, diagnosis and management of associated HSV-related diseases. The sensory nervous system, rather than skin and mucous membranes, is the primary target of HSV infection. With the intention of extending the benefits of acyclovir, valacyclovir is now being explored in a number of HSV-related conditions. This review extends contemporary thinking about how new antiherpetic drugs might be put to greater therapeutic use in the future.