Antibody to herpes simplex virus type 2 as serological marker of sexual lifestyle in populations

OBJECTIVES

To examine the epidemiology of antibody to herpes simplex virus type 2 and to assess its suitability as a serological marker of sexual behaviour in populations with high and low prevalences.

DESIGN

Cross sectional survey.

SETTING

Department of genitourinary medicine and blood donation centre in central London.

SUBJECTS

Representative sample of 869 patients attending department between November 1990 and December 1991, and 1494 consecutive blood donors attending for donation between February and April 1992.

METHOD

Participants had a blood sample taken for antibody testing with a novel type specific assay and completed a questionnaire.

RESULTS

Prevalence of antibody differed significantly between the two groups (188/833 (22.7%) clinic attenders; 102/1347 (7.6%) blood donors). In both populations antibody was strongly associated with sex, sexual orientation, years of sexual activity, number of lifetime sexual partners, and past infection with sexually transmitted diseases after other factors were controlled for. Only 130 (45%) of all those with antibody had symptoms suggestive of genital herpes, and 79 (27.4%) had had genital herpes diagnosed. Of those without antibody to herpes simplex viruses type 1 and 2, 8.0% reported genital blisters or sores and 1.1% had had genital herpes diagnosed by a doctor.

CONCLUSIONS

The strong relation between herpes simplex virus type 2 and sexual lifestyle suggests that the presence of antibody to the virus may be suitable for use as an objective, serological marker of patterns of sexual behaviour in different populations. These data show that only a minority of those infected with herpes simplex virus type 2 have a diagnosis of genital herpes or express clinical symptoms, making serological determinants of infection essential for epidemiological studies.

Sexually transmitted infections and risk behaviours in women who have sex with women

OBJECTIVES

To assess the prevalence of sexually transmitted infections (STIs) and blood borne viruses, risk behaviours, and demographics in women who have sex with women (WSW).

METHODS

Retrospective cross sectional study using a multivariate model. Demographic, behavioural, and morbidity data were analysed from standardised medical records of patients attending a public STI and HIV service in Sydney between March 1991 and December 1998. All women with any history of sex with a woman were compared with women who denied ever having sex with another woman (controls).

RESULTS

1408 WSW and 1423 controls were included in the study. Bacterial vaginosis (BV) was significantly more common among WSW (OR 1.7, p < 0.001). Abnormalities on cervical cytology were equally prevalent in both groups, except for the higher cytological BV detection rate in WSW (OR 5.3, p = 0.003). Genital herpes and genital warts were common in both groups, although warts were significantly less common in WSW (OR 0.7, p = 0.001). Prevalence of gonorrhoea and chlamydia were low and there were no differences between the groups. The prevalence of hepatitis C was significantly greater in WSW (OR 7.7, p < 0.001), consistent with the more frequent history of injecting drug use in this group (OR 8.0, p < 0.001). WSW were more likely to report previous sexual contact with a homo/bisexual man (OR 3.4, p < 0.001), or with an injecting drug user (OR 4.2, p < 0.001). Only 7% of the WSW reported never having had sexual contact with a male.

CONCLUSION

We demonstrated a higher prevalence of BV, hepatitis C, and HIV risk behaviours in WSW compared with controls. A similar prevalence of cervical cytology abnormalities was found in both groups. Measures are required to improve our understanding of STI/HIV transmission dynamics in WSW, to facilitate better health service provision and targeted education initiatives.

Prospects for control of herpes simplex virus disease through immunization

Herpes simplex viruses (HSVs) can cause a variety of infections, including genital herpes. Despite effective antiviral therapy, HSV infections remain a significant worldwide public health problem. Vaccines offer the best hope for controlling spread and limiting HSV disease. This article discusses the pathogenesis and immunobiology of mucocutaneous HSV infections, summarizes the spectrum of diseases caused by HSV, and provides a review of the field of HSV vaccine research. This article also discusses what might be realistically expected of a vaccine intended for control of genital herpes and explores the question of whether a vaccine that is effective in controlling genital HSV disease might also be effective in controlling nongenital HSV disease. The efficacy of such vaccines for the full spectrum of HSV disease will eventually determine the timing and targeting of immunization, ranging from selective immunization in preadolescence to universal childhood immunization as part of the routine childhood regimen.

Social and sexual risk factors for bacterial vaginosis

BACKGROUND

A number of sexual and social risk factors for bacterial vaginosis (BV) have been identified. However, many previous studies have used small numbers of patients, or highly selected or convenience samples, or poorly defined populations. This study aims to clarify potential sexual and non-sexual risk factors for BV.

METHODS

Women attending the Sydney Sexual Health Centre with BV, between March 1991 and July 1999, were included. Controls were randomly selected women without BV. Information on the demographics, clinical findings, and sexual and non-sexual risk behaviours were extracted from the clinic database and analysed using SPSS and SAS. A logistic regression model was used to establish which associations with BV persisted.

RESULTS

890 women with BV and 890 controls were studied. Factors that were independently associated with BV were > or =3 male sexual partners in the past 12 months (OR = 1.60, 95% CI: 1.19 to 2.04), at least one female sexual partner in the past 12 months (OR = 2.1, p = 0.003), a past pregnancy (OR = 1.5, p<0.0006), and smoking. In contrast, women with BV were significantly less likely to have used hormonal contraception (OR = 0.60, 95% CI: 0.51 to 0.81) or to have used condoms consistently (OR = 0.5, 95% CI: 0.31 to 0.71) than controls.

CONCLUSION

Our findings may be important for planning a preventive strategy for BV by discouraging smoking and increasing condom use and hormonal contraception among women.

Entamoeba histolytica as a commensal intestinal parasite in homosexual men

Entamoeba histolytica is considered to be an uncommon, imported organism in the United Kingdom and in many parts of North America, but recent attention has been drawn to the possibility of sexual transmission of this parasite among homosexual men. To determine the prevalence and clinical importance of enteric parasitic infections in men attending a clinic in London for the treatment of sexually transmitted diseases, we studied 354 randomly selected patients who provided a single stool sample that was examined for E. histolytica and other intestinal parasites. Forty-five of the 225 homosexual patients (20 percent) were infected with E. histolytica, but no such infections were found among the 129 heterosexual subjects (P less than 0.0001). With the use of isoenzyme electrophoresis, 34 of the 45 E. histolytica isolates were classified according to zymodeme. All were Zymodeme I or III, which are considered to be nonpathogenic. There was no correlation between the presence of E. histolytica and gastrointestinal symptoms. These findings suggest that E. histolytica is a common commensal in the homosexual population and that, in the absence of evidence of invasive disease, treatment of persons passing cysts of the organism may have little practical benefit.

Anal and cervical intraepithelial neoplasia: possible parallel

This study evaluated prospectively the use of an endoscope in examination of the anal canal for the detection of premalignant lesions. All patients underwent endoscopy and anal epithelial biopsy; the biopsy samples were examined histologically and human papillomavirus (HPV) DNA hybridisation was done. No evidence of anal intraepithelial neoplasia (AIN) was found in 20 control patients with anal fissure or fistula. Of 82 patients with anal HPV infection, 23 had evidence of AIN. The prevalence of AIN was significantly higher among homosexual than among heterosexual men (17 of 28 vs 1 of 26) with anal HPV infection. Of 28 women with anal HPV infection, 10 had cervical intraepithelial neoplasia (CIN); 5 of the 10 also had AIN, whereas no woman had AIN in the absence of CIN. The study shows that AIN occurs and can be diagnosed endoscopically in a manner similar to CIN. Further detailed prospective studies on the natural history of AIN and of groups at risk are required.

Dosage and safety of long-term suppressive acyclovir therapy for recurrent genital herpes

131 patients with frequently recurring genital herpes were treated for 1 year with reducing doses of oral acyclovir. The time to first recurrence in patients who commenced therapy on 400 mg twice a day was statistically significantly shorter than those on 200 mg four times a day (p less than 0.02) and as the total daily dose and frequency of therapy were lowered so the time to first recurrence was shortened. By the end of 60 days on 200 mg once a day (the lowest daily dose) 56% of patients had recurrences. Patients showed a marked reduction in the frequency of recurrence during therapy (from a mean of 1.1 per 28 days before to 0.11 during treatment, p = 0.0001). After stopping treatment the frequency of recurrences (0.71 per 28 days) was significantly less than the pre-treatment period (p = 0.001). No important side-effects were seen. It is concluded that long-term suppression with acyclovir is safe and effective for patients with recurrent genital herpes.

Prophylactic oral acyclovir in recurrent genital herpes

56 patients with frequently recurring genital herpes were treated in a randomised double-blind trial with either oral acyclovir 200 mg four times a day or placebo for 12 weeks. 29 patients received the drug and 27 the placebo. The mean recurrence rate per month of treatment was 1.4 in the placebo-treated patients and 0.05 in the acyclovir group. Median time to the first recurrence after the start of therapy was 14 days in the placebo group compared with 100 days in the acyclovir group. After the end of treatment the recurrence rate was similar in the two groups. Prophylactic oral acyclovir seems to be an effective treatment for patients with frequently recurring genital herpes.

A randomised placebo controlled trial of suppressive acyclovir in late pregnancy in women with recurrent genital herpes infection

OBJECTIVE

To evaluate the efficacy and safety of a suppressive course of acyclovir in late pregnancy in women with recurrent genital herpes infection on the incidence of viral shedding, herpes lesion development and caesarean section for recurrent genital herpes.

DESIGN

Double-blind, randomised placebo controlled clinical trial.

SETTING

A department of genitourinary medicine in Sheffield and an antenatal clinic in London.

POPULATION

Pregnant women with recurrent genital herpes infection at < 36 weeks of gestation.

METHODS

Participating women were given acyclovir 200 mg four times a day (or matching placebo) from 36 weeks of gestation until the time of delivery. Women were seen weekly and viral cultures were obtained from the cervix and vulva. Decisions regarding mode of delivery were left to the discretion of the attending obstetrician.

MAIN OUTCOME MEASURES

Delivery by caesarean section for recurrent genital herpes infection. Number of episodes of recurrent genital herpes infection and number of episodes of asymptomatic viral shedding during the treatment period. In addition blood was taken at two weekly intervals to determine acyclovir levels.

RESULTS

The total number of women recruited was 63 (31 received acyclovir and 32 received placebo). The number of women undergoing delivery by caesarean section for recurrent herpes at the time of delivery was 12 (19%). The odds ratio for delivery by caesarean section in women taking acyclovir, compared with those taking placebo, was 0.44 (95% CI 0.09-1.59). The odds ratio for clinical recurrences during treatment was 0.10 (95% confidence interval 0.00-0.86) and the odds ratio for clinical recurrence or asymptomatic shedding during treatment was 0.32 (95% CI 0.05-1.56).

CONCLUSION

This trial was unable to demonstrate that acyclovir can significantly decrease the number of caesarean section deliveries; however, the number of clinical recurrences was significantly reduced. Two episodes of asymptomatic virus shedding both occurred in women taking acyclovir. At the present time there is little evidence to suggest that acyclovir should be used outside randomised controlled trials for the suppression of recurrent genital herpes infection during pregnancy.

Prevalence of infection with herpes simplex virus types 1 and 2 in Australia: a nationwide population based survey

BACKGROUND

Studies demonstrating previous herpes simplex virus (HSV) type 2 infection as a risk factor for HIV transmission, and the development of a HSV vaccine candidate, have emphasised the need for worldwide population based studies of HSV seroprevalence. The only nationwide seroprevalence studies have been conducted in the United States.

METHODS

An Australia-wide, population based study of HSV-1 and HSV-2 seroprevalence was conducted, using serum and sociodemographic data collected between 1999-2000, for a representative study of risk factors for diabetes in over 11 000 adults. A stratified random sample of 4000 was tested for HSV-2 and 1000 for HSV-1, with sampling and weighting for various demographic factors.

RESULTS

Seroprevalence of HSV-2 in Australian adults was 12%. Prevalence in women (16%) was twice that in men (8%). Rural populations had a lower prevalence (9%) than metropolitan (13%), and Indigenous had a higher prevalence (18%) than the non-Indigenous populations (12%). The seroprevalence of HSV-1 was 76% with significant differences by age group, sex and Indigenous status.

CONCLUSION

These are the first nationwide data to compare with US studies. HSV-2 infection is less common in Australia than the United States, and this will allow planning for combating HIV transmission in high prevalence populations in northern Australia. In addition, the high HSV-1 seroprevalence will be important for future deployment of genital herpes vaccines.

New developments in the epidemiology, natural history and management of genital herpes

The prevalence of genital herpes is increasing in several populations worldwide. Factors that may be contributing to this increase include greater numbers of sexual partners, the high frequency of asymptomatic infections, poor use of safe sexual practices, and possibly the decreased incidence of childhood oral herpes simplex virus infection. Transmission occurs via skin-to-skin or mucous membrane contact during periods of viral shedding when lesions are present but may also occur when the patient is unaware of the lesions or when lesions are not clinically apparent. This has important implications for strategies to prevent transmission of the disease. The introduction of the antiherpes agent, acyclovir, and more recently famciclovir and valacyclovir, facilitates the management of genital herpes. Treatment of first-episode genital herpes reduces the severity and duration of symptoms, time to lesion healing, and cessation of viral shedding. Episodic treatment of recurrences as they occur may be of benefit to some patients. Daily suppressive therapy significantly reduces the frequency of recurrences and asymptomatic viral shedding. Accordingly, patients who experience frequent or severe recurrences, those particularly troubled by their disease, and those who wish to reduce the frequency of asymptomatic infection generally prefer suppressive therapy. The possibility that suppressive therapy may have an impact on transmission of the disease is currently under investigation. Antiviral treatments have important implications for public health and may help reduce the psychological and psychosocial impact of genital herpes on individual patients.

HIV, sexually transmitted infections, and risk behaviours in male commercial sex workers in Sydney

OBJECTIVES

To assess prevalence of HIV and sexually transmitted infections (STIs), risk behaviours, and demographics in male commercial sex workers (CSWs)/prostitutes in Sydney.

METHODS

Retrospective, cross sectional study with two comparison groups. Demographic, behavioural, and morbidity data were analysed from standardised medical records of patients attending a public STI and HIV service in Sydney between January 1991 and March 1998. Two comparison groups were used: female CSWs and non-CSW working homosexual men who attended over the same time.

RESULTS

94 male CSWs, 1671 female CSWs, and 3541 non-CSW working homosexual men were included. The prevalence of HIV in male CSWs tested (6.5%) was significantly greater than in female CSWs (0.4%, p = 0.0001), but less than in non-CSW homosexual men (23.9%, p < 0.0001). Genital warts occurred significantly more frequently in male CSWs than in comparison groups. Prevalence of other STIs was similar in all groups. Male CSWs saw significantly fewer clients per week than female CSWs and male and female CSWs used condoms with almost all clients. Male CSWs reported significantly more non-work sexual partners than female CSWs and non-CSW homosexual men and were significantly more likely to have unprotected penetrative sex with their non-work partners than non-CSW homosexual men. Injecting drug use was significantly more frequent in male CSWs than in both comparison groups.

CONCLUSIONS

Although male CSWs use condoms with clients, they are more likely to practise unsafe sex with non-work partners (especially women) and inject drugs than female CSWs and non-CSW homosexual men. Some men with HIV are working within the commercial sex industry. Targeted health education to encourage safer drug use and safer sex outside work is needed.

Herpes simplex virus type 1 infection: a sexually transmitted infection of adolescence?

OBJECTIVES

To examine the factors associated with antibodies to herpes simplex virus type 1 (HSV-1).

DESIGN

Cross sectional study with HSV-1 antibody testing performed by University of Washington western blot assay.

SETTING

Central London STD clinic (1990-1) and central London blood donation centre (1992).

PARTICIPANTS

Representative sample of 869 new and rebooked GUM clinic attenders and 1494 consecutive blood donors.

RESULTS

The prevalence of HSV-1 antibody among clinic attenders was 60.4% (95% CI 57.0 to 63.7) and among donors was 46.1% (95% CI 43.5 to 48.7). HSV-1 antibody was independently associated with increasing age in both populations (p<0.001). Among clinic attenders, HSV-1 was less common among heterosexual men than women and homosexual men (p<0.005), and was more common among black people (p=0.001) and those of lower socioeconomic status (p=0.05). Among blood donors, being single rather than married was independently associated with HSV-1 infection (p=0.03). Early age at first intercourse was strongly associated with presence of HSV-1 in both populations. The adjusted odds of HSV-1 among GUM clinic attenders was 0.37 (95% CI 0.21 to 0.65) for someone aged 20 at first intercourse compared with someone aged <or=15. Among blood donors, those aged 20 had an adjusted odds of 0.64 (95% CI 0.39 to 1.05) compared with someone aged 15. HSV-1 was not associated with increasing number of lifetime partners after adjustment for other factors.

CONCLUSIONS

Genital herpes due to HSV-1 antibody is increasing in the United Kingdom, particularly among young people. In this study we found that HSV-1 was strongly associated with early age of first sexual intercourse, which may reflect the sexual practices of people initiating sex in this age group.

Randomised controlled trial of adenine arabinoside 5'-monophosphate (ARA-AMP) in chronic hepatitis B virus infection

A randomised controlled trial was conducted in 29 HBV carriers who had been HBs and HBe antigen positive for more than six months. Fifteen patients were treated with ARA-AMP 10 mg/kg/day given as intramuscular injections 12 hours apart for five days followed by 5 mg/kg/day for 23 days. The 14 controls received no treatment. Serum HBV-DNA polymerase, and HBV-DNA decreased in all patients during therapy. Six treated patients lost serum HBV-DNA polymerase, HBV-DNA and HBeAg, HBsAg concentrations decreased, and five developed anti-HBe. One of these six patients lost HBsAg and developed anti-HBs. No such changes were observed in the control group over a similar 18 month period of observation. A four week course of ARA-AMP inhibits HBV replication and in a significant minority of patients this is long lasting and is associated with a reduced level of inflammatory activity in the liver.

Relationship between antibodies to herpes simplex virus (HSV) and symptoms of HSV infection

To determine the relationship between antibodies to herpes simplex virus (HSV) types 1 and 2 and diagnosis of orolabial and genital herpes, a cross-sectional survey was done among 869 sexually transmitted disease clinic attendees and 1594 blood donors in London. Among clinic attenders, the prevalence of HSV-1 infection was 59.5% and that of HSV-2 infection was 22.7%, and among blood donors the prevalence was 44.6% and 7.6%, respectively. The sensitivity and specificity of a diagnosis of oral herpes for the presence of HSV-1 antibody was almost identical in the 2 groups (clinic attendees: sensitivity, 33.1%, and specificity, 91.4%; blood donors: sensitivity, 32.3%, and specificity, 94.3%). A diagnosis of genital herpes was less sensitive for antibody for HSV-2 among donors than among clinic attenders (P < .001); however, the specificity was similar in the 2 populations (clinic attendees: sensitivity, 32.1%, and specificity, 96.6%; blood donors: sensitivity, 17.5%, and specificity, 99.5%). False-positive clinical histories were also relatively common (clinic attenders, 12%; donors, 6%). The sensitivity of the diagnosis of genital herpes would be improved if accurate serologic assays for detection of HSV type-specific antibodies were more widely available.

Outcome of untreated infection with Entamoeba histolytica in homosexual men with and without HIV antibody

Among homosexual men the prevalence of infection with Entamoeba histolytica is high. To determine the clinical importance of this infection 55 homosexual men carrying the parasite were investigated in detail. No clinical, serological, or histological evidence of invasive amoebiasis was found in any of them. The patients were not treated and were followed up for 12 to 29 months (mean 21.6 months), during which period none developed symptoms that could be attributed to E histolytica. Spontaneous loss of the parasite occurred in 17 patients, some of whom later became reinfected. Sixteen patients had antibody to human immunodeficiency virus, and infection with E histolytica showed the same benign course in them as in the patients who did not have antibody. Throughout the study classification of the isolates of E histolytica consistently showed that they belonged only to non-pathogenic zymodemes. The findings provide further evidence that E histolytica in homosexual men is a commensal organism.

Risk factors for the acquisition of genital warts: are condoms protective?

OBJECTIVES

To characterise risk factors for the acquisition of genital warts and specifically to determine whether condoms confer protection from infection.

METHODS

A retrospective case-control study comparing demographic, behavioural, and sexual factors in men and women with and without newly diagnosed genital warts, who attended Sydney Sexual Health Centre (SSHC), an inner city public sexual health centre, in 1996. Data were extracted from the SSHC database. Crude odds ratios (OR) were calculated to compare cases and controls and significant factors were then controlled for using multivariate logistic regression to obtain adjusted odds ratios (ORs).

RESULTS

977 patients with warts and 977 controls matched by sex and date of attendance were included. In both sexes, univariate analysis revealed that younger age, more lifetime sexual partners, failure to use condoms, greater cigarette smoking and alcohol consumption were associated with warts, and there was a negative association with previous infection with Chlamydia trachomatis, Neisseria gonorrhoeae, hepatitis B, and genital herpes. In males, on multivariate analysis, factors which remained significant were younger age, more lifetime sexual partners; failure to use condoms, greater cigarette smoking, and previous chlamydia. In women, factors which remained significant were younger age, more lifetime sexual partners, condom use, marital status, and previous infections with Chlamydia trachomatis and herpes.

CONCLUSIONS

Independent risk factors for genital warts include younger age, greater number of lifetime sexual partners, and smoking. Consistent condom use significantly reduces the risk of acquiring genital warts.

Increase in rates of herpes simplex virus type 1 as a cause of anogenital herpes in western Sydney, Australia, between 1979 and 2003

BACKGROUND/OBJECTIVE

Recent studies suggest that herpes simplex virus type 1 (HSV-1) is becoming more common as a cause for genital herpes, relative to HSV-2. We aimed to calculate trends in HSV type from isolates and serology samples sent to a reference virology laboratory in New South Wales (NSW), Australia.

METHODS

We compared the proportions of HSV-1 and HSV-2 positive samples, adjusting for age and sex of source patient, in three datasets: anogenital isolates from 1979 to 1988; anogenital isolates from 1989 to 2003; and HSV type specific IgM seropositivity from 1994 to 2003.

RESULTS

The number of specimens in each analysis was 17 512, 4359, and 497, respectively. There was a progressive rise in the proportions of typed specimens being HSV-1 in all analyses. The proportion of isolates that were HSV-1 ranged from 3% in 1980 to 41% in 2001. Female sex and age under 25 were associated with a greater proportion of HSV-1 isolates in both time periods. In the period 1979-88, comparing the proportions of HSV-1 and HSV-2 gave an odds ratio (OR) per additional year of 1.24 (95% confidence interval (CI) 1.20 to 1.27; p<0.005) after adjustment for age and sex. In the period 1989-2003 there was a steeper rise in the proportion of isolates that were HSV-1 in samples from younger individuals (OR per year 1.17, 1.12 to 1.22) compared to those over 25 (OR per year 1.06, 1.03 to 1.08). The rise in the proportion of IgM seropositive results reactive for HSV-1 compared to HSV-2 gave an OR of 1.36 per year (1.26 to 1.47; p<0.005).

CONCLUSIONS

These data suggest that HSV-1 has become more common as a cause of anogenital herpes in NSW.

Human immunodeficiency virus infection and genital warts as risk factors for anal intraepithelial neoplasia in homosexual men

The incidence of anal intraepithelial neoplasia (AIN) was studied in a group of 210 homosexual and bisexual men. The presence of genital warts and human immunodeficiency virus (HIV) infection was assessed as risk factors for the development of AIN. In all, 74 (35 per cent) of the group had histological evidence of AIN. The relative risk of being positive for HIV on AIN (relative to being negative for HIV) was 1.58 (95 per cent confidence interval (c.i.) 1.01-2.48). The relative risk of anal warts on AIN (relative to absence of anal warts) was 4.70 (95 per cent c.i. 1.81-12.20). Logistic regression analysis showed no significant interactive effect between HIV and anal warts on the risk of AIN. It is concluded from the results of a Mantel-Haenzel analysis that the presence of anal warts and HIV infection are independent risk factors for the development of AIN in homosexual and bisexual men.

Primary and secondary syphilis, 20 years' experience. 2. Clinical features

The notes of 946 patients with primary and 854 with secondary syphilis were retrospectively reviewed. Of the 184 heterosexual men with primary syphilis, 182 (99%) had chancres affecting the penis, compared with 467 (64%) of the 728 homosexual men (p less than 0.0001). Anorectal chancres occurred in 249 (34%) of homosexual men. The commonest features of secondary syphilis included a rash, lymphadenopathy, and mucous patches of the mouth or genital area. Hepatitis, meningitis, other neurological problems, iridocyclitis, and periostitis were all exceptionally rare. The clinical features of primary and secondary syphilis do not appear to have changed in recent years.

Risk of recurrence after treatment of first-episode genital herpes with intravenous acyclovir

To determine whether intravenous acyclovir treatment for a first episode of genital herpes could prevent or reduce subsequent recurrences, we combined and analyzed the results of two independently conducted, randomized, double-blind, placebo-controlled studies. Sixty-one patients were enrolled in the two trials; 30 received the drug, and 31 received placebo. At entry the demographic, epidemiologic, and clinical features of acyclovir- and placebo-treated patients from the two centers showed no significant differences. The median time to the first recurrence and the frequency of recurrences showed no significant differences when acyclovir and placebo recipients infected with either herpes simplex virus type 1 (HSV-1) or herpes simplex virus type 2 (HSV-2) were compared. However, irrespective of treatment, the median time to the first recurrence was significantly longer (293 days vs. 69 days; P less than .02) and the frequency of recurrence significantly less (0.11 recurrences per month vs. 0.43 recurrences per month; P less than .01) among patients with HSV-1 infection as compared with those who had HSV-2. It is concluded that in patients with first-attack genital herpes, the type of HSV is the most important determinant of subsequent recurrences and that intravenous acyclovir has little effect on subsequent recurrences.

Sexual and demographic risk factors for herpes simplex type 1 and 2 in women attending an antenatal clinic

OBJECTIVE

To establish risk factors for the presence of HSV-2 and HSV-1 infections in pregnant women. DESIGN, POPULATION, AND SETTING: A prospective study of 3306 women attending the antenatal department Westmead Hospital, Sydney, between June 1995 and April 1998.

METHODS

Women completed a self administered questionnaire to establish risk factors for the presence of HSV-2 and HSV-1. Sera were tested for antibodies to HSV-2 and HSV-1. Data were analysed using SPSS and SAS.

MAIN OUTCOME MEASURES

Seroprevalence of and risk factors for HSV-2 and HSV-1.

RESULTS

375 (11.3% (95% CI 10.3-12.5)) women were HSV-2 antibody positive. Increasing age, Asian country of birth, lower education level, public hospital status, confirmed genital herpes, a partner with genital herpes, early age of first sex, more than one lifetime sexual partner, and previous chlamydia infection were independently associated with HSV-2 seropositivity. Of 408 women tested for HSV-1 antibodies, 323 (79.2% (95% CI 74.9-83.0)) were positive. Oral herpes, oral blisters or sores, and being HSV-2 seropositive were independently associated with HSV-1 seropositive status. When the logistic regression model was rerun without HSV-2 status, parity of two or more and one or more sexual partners in the past 3 months were significant predictors of HSV-1 seropositivity.

CONCLUSIONS

The presence of antibodies to HSV-2 and HSV-1 is related to a number of sexual and demographic risk factors. Public health campaigns directed at encouraging young people to delay the onset of sexual activity and reduce the number of sexual partners need to be evaluated. However, the possible availability of an HSV-2 vaccine that is able to protect over 70% of women offers the best hope for control of genital herpes.