Demographic rather than behavioral risk factors predict herpes simplex virus type 2 infection in sexually active adolescents

Exploration of gender differences of Chlamydia trachomatis infection amongst young people reveals limitations of using sexual histories to assess risk in high-prevalence areas

Summary

In England, chlamydia positivity in young men occurs at a slightly older age group (20–24 years) than positivity among young women (16–20 years) but total rates of infection among the population aged under 25 years are similar. Where there is variation, explanations often focus on individual sexual risk behaviours. We aimed to explore the extent to which variations in chlamydia positivity could be explained by reasons for attendance and sexual behaviour at a sexual health clinic in a high-prevalence area of England. Data routinely collected during clinic appointments were extracted retrospectively from the medical records of 952 clinic users (634 women) aged 16 to 24. We tested for associations with chlamydia positivity using the Chi square statistic and multiple logistic regression for men and women separately; 19.5% of men tested positive (95% CI: 15.1–23.8) compared to 11.5% of women (95% CI: 9.0–14.0). Reporting a partner with symptoms or a sexually transmitted infection diagnosis was significantly associated with a positive diagnosis (Men OR: 3.14, 95% CI: 1.5–6.25; Women OR: 3.78, 95% CI: 1.83–7.83). All other reasons for attendance and all sexual behaviour variables were not significantly associated with a positive diagnosis. Differences in chlamydia positivity between men and women attending this service cannot be explained by individual sexual behaviours found to be associated with higher risk of infection in national studies. Our findings question the utility of individual behavioural data routinely collected during clinic appointments for predicting risk of sexually transmitted infections in high-prevalence areas.

A pooled analysis of the effect of condoms in preventing HSV-2 acquisition

BACKGROUND

The degree of effectiveness of condom use in preventing the transmission of herpes simplex virus 2 (HSV-2) is uncertain. To address this issue, we performed a large pooled analysis.

METHODS

We identified prospective studies with individual-level condom use data and laboratory-defined HSV-2 acquisition. Six studies were identified through a review of publications through 2007: 3 candidate HSV-2 vaccine studies, an HSV-2 drug study, an observational sexually transmitted infection (STI) incidence study, and a behavioral STI intervention study. Study investigators provided us individual-level data to perform a pooled analysis. Effect of condom use was modeled using a continuous percentage of sex acts during which a condom was used and, alternatively, using absolute numbers of unprotected sex acts.

RESULTS

A total of 5384 HSV-2-negative people at baseline contributed 2 040 894 follow-up days; 415 persons acquired laboratory-documented HSV-2 during follow-up. Consistent condom users (used 100% of the time) had a 30% lower risk of HSV-2 acquisition compared with those who never used condoms (hazard ratio [HR], 0.70; 95% confidence interval [CI], 0.40-0.94) (P = .01). Risk for HSV-2 acquisition increased steadily and significantly with each unprotected sex act (HR, 1.16; 95% CI, 1.08-1.25) (P < .001). Condom effectiveness did not vary by gender.

CONCLUSIONS

To our knowledge, this is the largest analysis using prospective data to assess the effect of condom use in preventing HSV-2 acquisition. Although the magnitude of protection was not as large as has been observed with other STIs, we found that condoms offer moderate protection against HSV-2 acquisition in men and women.

Herpes simplex virus type 2 among Mexican high school adolescents: prevalence and association with community characteristics

BACKGROUND

We undertook this study to estimate the prevalence and correlates of herpes simplex virus type 2 (HSV-2) among Mexican adolescents in high school.

METHODS

This was a cross-sectional analysis using data that had been collected to evaluate a school-based HIV prevention intervention. As part of the final round of evaluation, capillary blood samples were taken from volunteers to test for antibodies to HSV-2. The effect of each school's seroprevalence on the probability of an individual being seropositive was estimated, and the results were grouped by town to evaluate the association between characteristics of the locality and student HSV-2 seroprevalence.

RESULTS

Dried blood spots were collected for 80% of the 1607 participants in the survey who reported that they were sexually active. Of these samples, 21% tested positive for HSV-2 antibodies, with no significant difference in prevalence between men and women. Seroprevalence among schools ranged from 0 to 57%. The number of sex workers registered in the locality was the most important covariate of seroprevalence, with each additional female sex worker (FSW) per 1000 women between 18 and 45 years of age in the town associated with an increase of 1% in the seroprevalence of HSV-2.

CONCLUSIONS

Characteristics of adolescents' micro-environments that influence their pool of potential sexual partners and the likelihood that these partners are HSV-2 positive may be more important predictors of the risk of STI infection than self-reported condom use.

Risk behaviors of 15-21 year olds in Mexico lead to a high prevalence of sexually transmitted infections: results of a survey in disadvantaged urban areas

BACKGROUND

Due to the fact that adolescents are more likely to participate in high-risk behaviors, this sector of the population is particularly vulnerable to contracting sexually transmitted infections (STIs) and resultant health problems.

METHODS

A survey was carried out among adolescents from poor homes in 204 small-urban areas of Mexico. Information was collected in relation to risk behaviors and socio-economic environment. A sub-group of the participants also provided blood and urine samples which were analyzed to detect sexually transmitted infections.

RESULTS

The presence of Chlamydia was detected in nearly 8% of participants who had stated that they were sexually active (18%) and approximately 12% were positive for herpes type 2-specific antibodies. For both, a greater proportion of girls resulted positive compared to boys. The presence of these biological outcomes of sexual risk behavior was associated with other risk behaviors (smoking), but not with self-reported indicators of protected sex (reported use of condom during most recent sexual activity).

CONCLUSION

The results presented in this study show a startlingly high prevalence of HSV-2 among sexually active Mexican adolescents in poor urban areas, suggesting that this group has participated to a great extent in risky sexual practices. The relationships between socioeconomic environment and adolescent risk behavior need to be better understood if we are to design preventive interventions that modify the determinants of risk behaviors.

Sex with women as a risk factor for herpes simplex virus type 2 among young men who have sex with men in Baltimore

BACKGROUND

Herpes simplex virus type 2 is common among MSM and is a risk factor for transmission of HIV. The findings of studies investigating the relationship between infection with HSV-2 and number of sex partners among MSM are inconsistent and rarely distinguish between male and female partners.

GOAL

To determine the prevalence and risk factors for infection with HSV-2, including the number and gender of sex partners, in a group of MSM in Baltimore, MD.

STUDY

This was a cross-sectional study among young MSM in Baltimore.

RESULTS

Of the blood samples from 824 participants, 19.3% had HSV-2 antibodies. After adjusting for known HSV-2 correlates, independent predictors of HSV-2 seropositivity included HIV seropositivity, black race, older age, number of lifetime female sex partners, recent unprotected receptive anal intercourse with a man.

CONCLUSIONS

This study suggests that female sex partners may be an important source of HSV-2 infection among young bisexual MSM. After adjusting for known HSV-2 correlates, the number of lifetime female but not male sex partners was independently associated with HSV-2. These results highlight the need for HSV-2 prevention and treatment efforts targeting MSM who also have sex with women. Future investigations of HSV-2 and sexual behavior among MSM need to distinguish between male and female sex partners.

Herpes Simplex Virus Infections of the Newborn

Herpes simplex virus (HSV) infection in newborns is an important cause of death and permanent neurodevelopmental disability among young children. Neonatal HSV infections can be categorized as 1) mucocutaneous (skin-eyes-mouth), 2) disseminated, or 3) encephalitic. In addition, congenital HSV infection, a distinct clinical syndrome, accounts for approximately 5% of HSV infections identified in the neonatal period. Polymerase chain reaction greatly enhances the clinician's ability to diagnosis HSV infections, but as many as 25% of infants with neonatal HSV encephalitis have negative polymerase chain reaction studies of cerebrospinal fluid. Infants with proven or suspected HSV infections should receive acyclovir 60 mg/kg/day divided every 8 hours for 14 days if disease is restricted to the skin, eyes, or mucous membranes and for 21 days if the infant has disseminated infection or encephalitis. The benefit of long-term suppression therapy after completion of the initial treatment regimen has not been established definitively. Despite therapy with acyclovir, the best available anti-HSV drug, a substantial number of HSV-infected infants with disseminated infections or encephalitis die or have long-term neurodevelopmental sequelae.

Predominant type 1 CMV-specific memory T-helper response in humans: evidence for gender differences in cytokine secretion

Cell-mediated memory immune responses to viral antigens are important for protection against viruses causing persistent or acute infections. This study compared the cytokine profile of memory T-helper cells specific for cytomegalovirus (CMV) in healthy CMV-seropositive men and women. The cytokine response reflected T(H)1 bias, with dominant secretion of interferon (IFN)-gamma along with moderate levels of tumor necrosis factor-alpha, interleukin (IL)-10, and IL-2. Analyzed by gender, women had higher and significant spontaneous release of IFN-gamma and CMV-specific IL-2 secretion. Similar analysis with herpes simplex virus-1 showed a trend toward higher cytokine responsiveness in women, but the differences were not statistically significant. In contrast, men had statistically significant higher influenza virus-specific tumor necrosis factor-alpha secretion. IL-4 and IL-5, both T(H)2 cytokines, were low for all three viruses. The results show a predominant T(H)1 antiviral cytokine T-help memory response with significant differences linked to gender. Such differences may have an impact in the design of immunization strategies against CMV.

Sexually transmitted infections, blood-borne viruses and risk behaviour in an Australian senior high school population—the SHLiRP study

Objectives: To determine the feasibility and acceptability of screening for sexually transmitted infections and blood-borne viruses and to study the profile of sexual activity and other risk behaviours in a senior high school population. Methods: In this descriptive study we provided sexual health education and screening to students from two senior high schools in the Australian Capital Territory. We collected behavioural data using a self-administered questionnaire. Urines and swabs were tested for Chlamydia trachomatis (Ct), Neisseria gonorrhoea (Ng), Trichomonas vaginalis (Tv) and human papilloma virus (HPV). Blood specimens were tested for hepatitis B and C, HIV, herpes simplex viruses (HSV-1 and HSV-2) and syphilis. Results: A total of 795 students participated (31% of the enrolled population; female to male ratio 60 : 40) and 67.0% were sexually active. Of 795 students, 644 (81.0%) were screened. Rates of infection were Ct 1.1% (95% CI: 0.4–2.6), HPV 11.7% (95% CI: 7.4–17.3), HSV-1 32.5% (95% CI: 28.9–36.3), HSV-2 2.4% (95% CI: 1.3–3.9), hepatitis B surface antigen 0.3% (95% CI: 0.04–1.1) and hepatitis C antibodies 0.7% (95% CI: 0.07–1.6). Only 22.3% (95% CI: 19.3–25.7) of students had immunity to hepatitis B. There were no cases of HIV, gonorrhoea, trichomoniasis or syphilis. Of the sexually active students, 49.2% (95% CI: 38.9–59.2%) reported never or only sometimes using condoms, 41.5% (95% CI: 32.2–52.3%) reported unsafe drinking, 33.3% (95% CI: 23.9–43.1%) were smokers and 1.9% (95% CI: 0.2–7.0%) reported injecting drug use. Conclusions: Rates of STI and blood-borne viruses and immunity to hepatitis B were low in this population, but unsafe sex and other risk behaviours were common. We have demonstrated that STI screening, including serological testing, was well accepted in a senior high school population.

Genital herpes in adolescents

Herpes simplex virus (HSV) infections occur commonly among adolescents. Most HSV-2 infections are genital, but genital herpes can be caused by either HSV-1 or HSV-2. Weighted means were calculated based on published seroprevalence data on adolescents from the United States and found HSV-1 rates of 53.1 percent for adolescent males and 49.4 percent for adolescent females. The weighted means for HSV-2 was 15 percent for adolescent females and 12 percent for adolescent males. Most individuals who are infected with HSV-2 are unaware of their infection. Healthcare providers of adolescents should consider genital herpes even when an adolescent presents with nonspecific genital symptoms. In this article, we review current recommendations for diagnosis and management and review the psychological sequelae that can be associated with having genital herpes. Finally, we discuss biomedical interventions that are being developed to help reduce the epidemic of HSV and the challenges that these interventions face with regard to implementation.

Longitudinal Risk of Herpes Simplex Virus (HSV) Type 1, HSV Type 2, and Cytomegalovirus Infections among Young Adolescent Girls

BACKGROUND

Cross-sectional seroprevalence studies indicate that infections with herpes simplex virus (HSV) types 1 (HSV-1) and 2 (HSV-2) and cytomegalovirus (CMV) are common. However, data on the rates of acquisition of these infections are limited.

METHODS

A 3-year longitudinal study of HSV-1, HSV-2, and CMV seroprevalence was conducted in a cohort of 174 adolescent girls (age at enrollment, 12-15 years).

RESULTS

At study entry, 41% of the girls reported a history of sexual activity, and by the end of the study, 73% reported a history of sexual activity. At enrollment, 71% of all participants were seropositive for CMV, 44% were seropositive for HSV-1, and 7% were seropositive for HSV-2. By the end of the study, 81% of the girls were seropositive for CMV, 49% were seropositive for HSV-1, and 14% were seropositive for HSV-2. Among girls with a history of sexual activity, 15.5% were HSV-2 seropositive at the beginning of the study, and 18.9% were HSV-2 seropositive at the end of the study. The attack rates, based on the number of cases per 100 person-years, were 13.8 for CMV infection and 3.2 for HSV-1 infection (among all girls) and 4.4 for HSV-2 infection (among girls with a history of sexual activity). Participants with preexisting HSV-1 antibodies were associated with a significantly lower attack rate for HSV-2 infection. A generalized estimating equation model indicated that participants with a longer history of sexual activity and those who had more sexually transmitted diseases during the 6-month periods before the study visits were more likely to be HSV-2 seropositive.

CONCLUSIONS

This longitudinal study of adolescent girls found high baseline CMV and HSV-1 seroprevalence rates and substantial attack rates for all 3 pathogens.

Effect of preexisting chronic disease on primary cesarean delivery rates by race for births in U.S. military hospitals, 1999-2002

BACKGROUND

A previous study of the United States Department of Defense healthcare beneficiaries reported elevated cesarean delivery rates for black and Asian women relative to white women that were independent of maternal socioeconomic status. This finding suggests that other maternal factors may explain the elevated rates. The purpose of this study was to examine the prevalence of specific chronic diseases identified as risk factors for complications during pregnancy, labor, and delivery, and to explore the strength of each disease to predict a cesarean outcome.

METHODS

United States military hospital discharge records from 1999 to 2002 for singleton births to women without a previous cesarean were used to calculate primary cesarean and chronic disease rates for diabetes, hypertension, cardiovascular disease, renal disease, anemia, asthma, sexually transmitted diseases, and substance abuse. Stepwise logistic regression was used to calculate adjusted odds ratios for dichotomized race and chronic disease indicators for five maternal age groups using the chi2 difference (p < 0.05) to identify significant variables for inclusion in the model. Primary cesarean delivery rates were then adjusted for the presence of chronic diseases that were significantly associated with a cesarean outcome.

RESULTS

Diabetes, genital herpes, and hypertension were significant predictors of cesarean use among all maternal age groups. Cardiovascular disease, renal disease, asthma, and anemia were predictors in some age groups. The remaining disease conditions were not significant predictors for cesarean delivery. Adjustment of cesarean rates for these chronic diseases did not significantly alter the differences in primary cesarean rates for black and Asian mothers relative to white mothers.

CONCLUSIONS

The presence of certain chronic conditions before pregnancy may increase the likelihood that a woman will deliver by cesarean section. Adjustment of cesarean rates for the presence of these chronic diseases, however, does not account for the difference in cesarean rates observed for white and minority mothers in the study population. The potential for underreporting of chronic diseases complicates a true assessment of the impact of chronic disease on cesarean delivery rate variations between white and minority women.

Sexual and demographic risk factors for herpes simplex virus type 2 according to schooling level among Mexican youths

BACKGROUND

Herpes simplex virus type 2 (HSV-2), the agent causing one of the most common sexually transmitted infections in sexually active individuals, is currently considered a public health problem. In Mexico, there have been no population-based studies of the prevalence and factors associated with HSV-2 infection among young students.

GOAL

The goal was to measure HSV-2 seroprevalence and identify possible associated factors among students in the state of Morelos, Mexico.

STUDY DESIGN

Through a cross-sectional population-based study involving students at 92 schools in the state of Morelos, Mexico, 898 students aged 11 to 24 years old were identified. All of them reported they had already initiated sexual activity and provided a blood sample to detect the presence of anti-HSV-2 antibodies through the Western blot technique. The association between risk factors and HSV-2 was evaluated through multiple logistic regression analysis with stratification by sex and schooling level.

RESULTS

In the population under study, the prevalence of HSV-2 seropositivity was 5.7% (51/898), and the ratio of females to males was 2:1. The prevalence of consistent condom use overall was 22.6% among the 898 students. For students in Morelos State, Mexico, the HSV-2 seroprevalence was higher among the youngest female students (9.5% among junior high school versus 3.3% among university students; P<0.001). The main factors associated with HSV-2 infection were sex (for females the risk was 2.2 times higher than for males; 95% CI, 1.2-3.9); junior high school status (2.5 times higher risk than university students (95% CI, 1.1-6.0); and having had same-sex sexual intercourse (3.5 times higher risk; 95% CI, 1.4-8.9).

CONCLUSION

In contrast with other reports, the HSV-2 seroprevalence was higher among younger people. This finding can be explained by a cohort effect of more exposition to behavioral risks, particularly an earlier age at first intercourse and very low use of condoms among youngest students. Longitudinal surveys about serological responses to HSV-2 infection in different age groups are warranted.

Testing for HSV-2 infection among pregnant teens: implications for clinical practice

OBJECTIVES

To pilot test the feasibility of screening pregnant teens for HSV-2 infection during their first prenatal visit.

STUDY DESIGN

A cross-sectional study of 127 African-American adolescent females recruited during their first attendance to a prenatal clinic in a large urban hospital. A rapid serologic test (POCkit, manufactured by Diagnology Inc.) was used to assess HSV-2. The test uses a membrane-based immunoassay to detect circulating IgG antibodies to a specific antigen obtained from HSV-2 (semi-purified glycoprotein G2).

RESULTS

More than one-fifth (21.3%) of the adolescents tested positive for HSV-2; only 1 adolescent was previously aware of her infection. Older adolescents and those reporting a history of other STDs were significantly more likely to test positive for HSV-2.

CONCLUSIONS

Testing for HSV-2 in early pregnancy may be an efficient strategy for (1) initiating patient education designed to promote adoption of protective behaviors among adolescents at risk of HSV-2 acquisition during the remainder of their pregnancy and (2) teaching those who test positive how to recognize symptoms of HSV-2 outbreaks; patients reporting recurrent outbreaks during pregnancy may benefit from predelivery assessment.

Congenital infections

Despite major medical advances, such as the introduction of the rubella vaccine and prolonged postnatal therapy of infants with congenital toxoplasmosis, intrauterine infections remain important causes of deafness, vision loss, and behavioral or neurologic disorders among children worldwide. This article describes the common pathogens causing intrauterine infections and summarizes the current status of diagnosis, treatment, and prevention.

Genital herpes simplex virus infection in the adolescent: special considerations for management

Genital herpes simplex virus (HSV) infections are increasingly common among adolescents. In developed countries, during the 1990s, adolescent HSV type 2 seroprevalence rates ranged from 4 to 30% depending on the population studied. The clinical diagnosis of genital herpes may be unreliable and laboratory testing is recommended. Aciclovir, valaciclovir, and famciclovir are three antiviral drugs that have proven efficacy in the treatment of genital herpes. These drugs can be used in the treatment of the first episode or for recurrent infections, or can be used long term to suppress recurrent infections. Once or twice daily administration regimens are preferable for adolescents for reasons of adherence, and because it avoids the need to take medication at school. Unproven remedies are used commonly and can be harmful. In addition to antiviral therapy, proper management of the adolescent with genital herpes should also include developmentally appropriate explanations of the diagnosis, treatment and potential complications, recommendations for symptomatic relief, screening for other sexually transmitted infections, and discussion of safer sexual practices. All adolescents should have follow-up visits to complete education and counseling and to assess compliance with antiviral therapy.

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

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