Confirmation of herpes simplex virus type 2 infections in herpes-like genital lesions by a simple complement-fixation test.

The presence of complement-fixing antibody to an early herpes simplex virus type 2 (HSV-2) antigen (the AG-4 antigen) was correlated with HSV-2 infection in the sera of patients with genital herpes. Eighty-eight per cent of sera taken two weeks after clinical diagnosis of a primary or recurrent herpes infection in patients, confirmed to have HSV-2 by virus isolation and typing, contained the anti-AG-4 complement-fixing antibody. None of the patients with genital HSV-1 had the antibody, and only 9% of controls or patients with facial HSV-1 infection had positive results for the antibody. This correlation was used to identify genital HSV-2 infections when either no virus sample had been taken or when virus isolations had been unsuccessful. Thus, a simple complement-fixation test can confirm an HSV-2 virus infection without isolation of the virus from the herpetic lesion.     

Confirmation of herpes simplex virus type 2 infections in herpes-like genital lesions by a simple complement-fixation test

The presence of complement-fixing antibody to an early herpes simplex virus type 2 (HSV-2) antigen (the AG-4 antigen) was correlated with HSV-2 infection in the sera of patients with genital herpes. Eighty-eight per cent of sera taken two weeks after clinical diagnosis of a primary or recurrent herpes infection in patients, confirmed to have HSV-2 by virus isolation and typing, contained the anti-AG-4 complement-fixing antibody. None of the patients with genital HSV-1 had the antibody, and only 9% of controls or patients with facial HSV-1 infection had positive results for the antibody. This correlation was used to identify genital HSV-2 infections when either no virus sample had been taken or when virus isolations had been unsuccessful. Thus, a simple complement-fixation test can confirm an HSV-2 virus infection without isolation of the virus from the herpetic lesion.     

Detection of varicella zoster virus in genital specimens using a multiplex polymerase chain reaction

OBJECTIVE: To compare the relative proportions of varicella zoster virus (VZV) and herpes simplex viruses in specimens obtained from the genital lesions of adults presenting with presumed genital herpes infection. METHODS: Swabs of genital lesions from 6210 patients attending general practices, infectious diseases clinics within hospitals, or sexual health centres for treatment of their genital lesions were tested using polymerase chain reaction (PCR) technology. The multiplexed PCR was capable of detecting herpes simplex virus types 1 and 2 (HSV-1, HSV-2), VZV, and cytomegalovirus in a single sample. RESULTS: A total of 2225 patients had viruses detected by PCR. HSV-1 was detected in 36%, HSV-2 in 61%, and VZV in 2.9% of PCR positive samples. Of the 65 patients with VZV genital infection, many were thought to have HSV infection before laboratory testing. CONCLUSIONS: The finding of VZV in nearly 3% of virus positive genital specimens demonstrates that this virus needs to be considered as a differential diagnosis for genital herpetic lesions. Advice provided to patients with VZV genital infection regarding the source of infection, likelihood of recurrence, and potential for transmission of the virus will be different from that given to patients with HSV infection.     

Sequential genital infections by herpes simplex viruses types 1 and 2: restriction nuclease analyses of viruses from recurrent infections

Virus isolated from a woman presenting with the first symptomatic episode of genital herpes was identified as herpes simplex virus type 1 (HSV-1) by restriction nuclease fingerprinting. Testing for IgM antibody to HSV indicated that the patient had recently contracted a new HSV infection. Virus microneutralization and the micro-solid phase radioimmunometric test for IgG, however, showed that the patient had had prior infection with herpes simplex virus type 2 (HSV-2); thus the HSV-1 infection was acquired despite the presence of antibody to HSV-2. Genital herpes recurred about four, seven, and nine months after the HSV-1 infection. Isolates from the latter three episodes all were of an identical strain of HSV-2 and were not recombinants or a mixture of the viruses. The data show that two distinctly different herpes simplex viruses can initiate genital infections in one individual and suggest that HSV-2 is more likely to recur than HSV-1.     

Recurrent genital herpes in a population attending a clinic for sexually transmitted diseases.

Patients with recurrent genital herpes attending a sexually transmitted disease clinic were studied and transmission of the infection was elucidated by evaluating serostatus in their partners. Of 84 patients attending for recurrent genital herpes, 94% had a herpes simplex virus type 2 (HSV-2) infection and only 6% (5 patients) a type 1 infection. The mean age of the patients was 36 years and the duration of their infection was up to 37 years (median 4 years). In most patients the number of recurrences had not decreased between the first year and the last year. About half had experienced a more severe first episode infection. Of the patients, 64% were not aware of asymptomatic shedding and the risk of sexual transmission without clinical symptoms. Of 67 steady partners of patients with genital HSV-2, 15% had a history of genital herpes. By HSV serology, HSV-2 antibodies (indicating subclinical genital herpes) were demonstrated in more than half of the partners. The duration of the relationship or condom use did not seem to influence the frequency of transmission to the partner, which may indicate an individual susceptibility for acquiring a genital HSV-2 infection. Eleven per cent of the patients were on suppressive antiviral therapy, while 39% had no experience of antiviral therapy. Type-specific HSV serology was found to be of value in counselling partners of patients with genital herpes.     

Duplex real-time polymerase chain reaction assay for detection and quantification of herpes simplex virus type 1 and herpes simplex virus type 2 in genital and cutaneous lesions

BACKGROUND: A sensitive and specific method for detecting herpes simplex virus type 1 (HSV-1) and herpes simplex virus type 2 (HSV-2) is important for diagnosing genital and cutaneous infections. GOAL: The goal of this study was to compare quantitative real-time polymerase chain reaction (qPCR) with virus culture for diagnosis of genital and cutaneous HSV-1 and HSV-2. STUDY DESIGN: A duplex qPCR system for quantification of DNA from HSV-1 and HSV-2 was developed. Duplicate swabs for PCR and virus culture were collected from 89 patients attending our sexually transmitted infection and dermatology clinic. RESULTS: The duplex qPCR had a linear measure interval of 10-10 copies/mL. The detection limit was between 1 and 5 copies per reaction. qPCR detected HSV in 57 (64%) specimens and virus was isolated in 45 (50%) cases. First-episode infections showed higher viral quantities with a median value of 4.2 x 10 copies per reaction compared with recurrent infections with 1.0 x 10 (P = 0.0002). HSV-1 was more likely to be the cause of first-episode genital infections (72%), and HSV-2 of recurrent and atypical genital manifestations (73%). CONCLUSION: Real-time PCR is a sensitive method for diagnosing genital herpes, and the duplex format is convenient for typing. The method increased the detection rate by 27% compared with virus culture.     

Natural history of genital herpes simplex virus type 1 infection

BACKGROUND: Herpes simplex virus type 1 (HSV-1) has been increasingly reported as a cause of genital herpes, yet there have been few studies on the long-term natural history of this infection.GOAL The goal was to examine the clinical course of genital HSV-1 infection. STUDY DESIGN: This was a cohort study of patients presenting with culture-proven primary genital HSV-1 infection. RESULTS: The median follow-up of the 77 patients was 736 days. The overall rate of recurrences was 1.3/year in the first year of infection, decreasing to 0.7/year in the second year. In the first year of infection, 43% of study patients did not have a recurrence. In the second year of infection, 67% of study patients did not have a recurrence. CONCLUSION: Genital HSV-1 recurs infrequently in most patients, and the rate decreases further in the subsequent years of infection. Because the prognoses of genital HSV-1 and HSV-2 infections differ, determination of the viral type is important for patient counseling.     

Herpes simplex virus type 1 is the prevailing cause of genital herpes in the Tel Aviv area, Israel

BACKGROUND AND GOAL: The changing epidemiology of genital herpes with the increasing importance of herpes simplex virus (HSV) type 1 prompted a study on the relative prevalence of HSV-1 and HSV-2 among cases of genital herpes in the Tel Aviv area, Israel. STUDY DESIGN: A retrospective laboratory-based study of positive genital and nongenital herpes cultures performed at the Beilinson Medical Center between 1993 and 2002. Data regarding the number of isolates of each type and the age and sex of patients with genital lesions were retrieved from the database. Cultures were performed using Vero cells, and positive results were confirmed and typed by immunofluorescence. RESULTS: A total of 285 positive genital cultures and 659 positive nongenital cultures were recorded. HSV-1 was identified in 189 (66.3%) of the positive genital specimens and in 656 (99.55%) of the nongenital specimens. HSV-1 was isolated in 174 of 262 (66.4%) female subjects and 15 of 23 (65.2%) male subjects. The proportion of HSV-1 genital isolates was 72.7% in patients 15 to 24 years of age, 62% in those 25 to 44 years, and 46% in those aged 45 years or older. Overall, the annual isolation rate of genital HSV-1 has not changed markedly over the years. CONCLUSION: Herpes simplex virus type 1 has clearly been the predominant HSV type isolated from genital specimens in the Tel Aviv area over the last decade.     

Epidemiology of recurrent genital herpes simplex virus types 1 and 2

OBJECTIVES: To describe the epidemiology of type specific recurrent genital herpes, and to compare the duration of recurrent genital lesions caused by herpes simplex virus (HSV) types 1 and 2. METHODS: Participants were enrolled at clinics across the United States. Adults suspected of having active genital herpes were eligible. Lesions were cultured for HSV and typed. Data from 940 participants with recurrent culture positive HSV lesions were analysed. Pearson's chi(2) and Fisher's exact tests, multivariate logistic regression models, and a stratified Cox proportional hazards model were used to compare epidemiological characteristics and lesion duration of HSV-1 and HSV-2. RESULTS: HSV-1 was present in 4.2% of the recurrent HSV culture positive lesions. HSV-1 was most prevalent among whites (6.5%) and individuals with 0-2 recurrences in the previous year (9.1%) and, among men, in those with rectal/perirectal lesions (13.2%). Longer lesion duration was not significantly associated with virus type (hazard ratio (HR) 0.95, 95% confidence interval (CI) 0.65 to 1.38, p = 0.79), but was associated with male sex (HR 0.85, 95% CI 0.74 to 0.99, p = 0.04), and HIV seropositivity (HR 0.62, 95% CI 0.48 to 0.81, p<0.01). CONCLUSIONS: The authors found that, in the United States, recurrent genital HSV-1 is relatively rare in the STD and HIV clinic setting, especially among black people. Among men, rectal/perirectal recurrent lesions are more likely to be caused by HSV-1 than are penile lesions. In addition, lesion duration depends on sex and HIV status but not virus type. These findings shed new light on the type specific epidemiology of recurrent genital HSV, and suggest that type specific testing can inform the prognosis and management of genital herpes.     

Development and use of a type-specific antibody avidity test based on herpes simplex virus type 2 glycoprotein G

OBJECTIVES: It is difficult to discriminate between lesions resulting from recently acquired versus established genital herpes simplex virus type 2 (HSV-2) infection. Methods not based on history or serum IgM status are needed. GOAL: Our goal was to use type-specific gG-2 antibody avidity determinations based on HerpeSelect HSV-2 enzyme-linked immunosorbent assay (ELISA) to identify new infections. STUDY: Sera (N = 168) from 71 patients with first-episode genital herpes and 45 sera from 21 patients with recurrent episodes were tested. RESULTS: Median avidity increased from 30.2 in sera drawn 6 weeks after infection (P <0.001). Patients with recurrent episodes and established HSV-2 infections (median, 6.1 years' duration) had higher avidity antibodies (median, 92.7; range, 55.1-100) than patients after first episodes (median, 33.7; range, 6.4-73.9; P <0.001). CONCLUSION: Avidity testing based on HerpeSelect ELISA could be a cost-effective method to identify patients with new HSV-2 infections.     

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.     

Epidemiology of genital herpes simplex virus infections in a community-based sample in France: results of the HERPIMAX study

OBJECTIVE: The objective of this study was to provide information on the prevalence of herpes simplex infections in the general population in Europe. GOALS: The goals of this study were to determine the prevalence of clinically probable genital herpes and the relationship between serotype and clinical expression in a French community-based sample. STUDY: A total of 4410 subjects chosen at random were serotyped for herpes simplex virus type 1 (HSV-1) and herpes simplex virus type 2 (HSV-2). Data on symptoms were obtained by questionnaire allowing retrospective diagnosis of clinically probable genital herpes. RESULTS: Questionnaire data and serotype were available for 3192 subjects. Seroprevalences of HSV-1 and HSV-2 were 65.6% and 15.5%, respectively. Prevalence of clinically probable genital herpes was 11.8%, identified in 11.1% of HSV-1-positive subjects and 26.8% of HSV-2-positive subjects, with a lower prevalence in those coinfected with both virus types. CONCLUSIONS: Clinically probable genital herpes was observed in one fourth of subjects with HSV-2 infections and in some subjects with HSV-1 infection. Coinfection with HSV-1 appeared to protect against symptom expression in subjects infected with HSV-2.     

Oral shedding of herpes simplex virus type 2

OBJECTIVES: Herpes simplex virus (HSV) 1 and HSV-2 reactivate preferentially in the oral and genital area, respectively. We aimed to define frequency and characteristics associated with oral shedding of HSV-2. METHODS: Demographic, clinical and laboratory data of patients with documented HSV-2 infection and at least one oral viral culture obtained were selected from the University of Washington Virology Research Clinic database. RESULTS: Of 1388 people meeting the entry criteria, 44 (3.2%) had HSV-2 isolated at least once from their mouths. In comparison with the 1344 people who did not have HSV-2 isolated from their mouth, participants with oral HSV-2 were more likely to be male (OR = 1.9, 95% CI 1.0 to 3.7), HIV positive (OR = 2.9, 95% CI 1.4 to 6.0), and homosexual (OR = 2.2, 95% CI 1.1 to 4.2), and to have collected a larger number of oral specimens (median 32 v 4, p<0.001). Of the 58 days with oral HSV-2 isolation, 15 (25%) occurred during newly acquired HSV-2 infection, 12 (21%) during a recurrence with genital lesions, three (5%) during a recurrence with oral lesions, and three (5%) during a recurrence with oral and genital lesions; 25 (43%) occurred during asymptomatic shedding. Oral HSV-2 was found less frequently than oral HSV-1 (0.06% v 1%, p<0.001) in people with HSV-1 and HSV-2 antibody, and less frequently than genital HSV-2 (0.09% v 7%, p<0.001). CONCLUSIONS: Oral reactivation of HSV-2 as defined by viral isolation is uncommon and usually occurs in the setting of first episode of genital HSV-2 or during genital recurrence of HSV-2.     

First episodes of genital herpes in a Swedish STD population: a study of epidemiology and transmission by the use of herpes simplex virus (HSV) typing and specific serology

OBJECTIVES: To determine the proportion of herpes simplex virus type 1 (HSV-1) and HSV type 2 (HSV-2) in first episodes of genital herpes. To evaluate the use of HSV specific serology for classifying first episodes of genital herpes and for defining HSV serostatus in the patients' sexual partners. METHODS: 108 consecutive patients with first episodes of genital herpes seen at three STD clinics in Sweden from 1995 to 1999 were included in the study. HSV culture and typing were performed and serum was tested for antibodies against a type common HSV antigen and a type specific HSV-2 antigen, glycoprotein G2 (gG2). A structured interview including questions about sexual behaviour and sexual partners was taken. "Steady" partners were offered a blood test for HSV serology and counselling. RESULTS: Of 108 patients, 11 had a negative HSV culture. Of the 97 who were HSV culture positive, 44% (43/97) were typed as HSV-1 and 56% (54/97) as HSV-2. For 86 of these 97 patients, HSV serology from the initial visit was available. Of 52 primary infections, thus initially seronegative, 64% were HSV-1 infections and of 19 female primary infections 16 (84%) were HSV-1. In 17% the first episode of genital herpes corresponded to the first clinical recurrence of an infection acquired earlier in life. There was a significant correlation between having orogenital sex and being infected with HSV-1 and also a history of labial herpes in the partner. Only 20% of partners of patients with an HSV-2 infection had a history of genital herpes. CONCLUSIONS: Almost half of first episodes of genital herpes are caused by HSV-1. In young women with a primary genital infection, HSV-1 is much more frequent than HSV-2. Besides HSV typing, we found specific HSV serology of value for classifying first episodes and for diagnosing a subclinical HSV-2 infection in partners. Anamnestic data supported the suggestion that the orogenital route of transmission was common in genital HSV-1 infections.     

Seroprevalence of herpes simplex virus type 1 and type 2 in Turkey

BACKGROUND: Herpes simplex virus (HSV) infections are among the most common infectious diseases in humans. The prevalence of herpes simplex viruses type 1 (HSV-1) and type 2 (HSV-2) varies widely across the world. HSV-2 infection is the primary cause of genital herpes. It is highly prevalent in human populations in many parts of the world, and is the most common cause of genital ulcer disease worldwide. In spite of the large prevalence and growing incidence of herpes simplex infection (HSV-1 and HSV-2), relatively few data have been published regarding the seroprevalence of herpes simplex infection, while no data exist regarding the Turkish population. METHODS: We aimed to investigate the prevalence of HSV-1 and HSV-2 in selected populations in Turkey. A cross-sectional study was conducted involving 2082 serum samples of 725 adults, 300 pregnant women, 200 blood donors, 483 sex workers and 110 patients with genital warts and 264 hotel staff in Istanbul, Turkey. All serum samples were assessed for HSV1 and HSV-2 IgG antibodies using an HSV-type specific, enzyme-linked immunosorbent assay (ELISA). RESULTS: The prevalence of HSV-2 and HSV-1 antibodies was 4.8 and 85.3% in sexually active adults; 5.5 and 96% in blood donors; 5 and 98% in pregnant women, 17.3 and 93.6% in patients with genital warts; 8.3 and 97.3% in hotel staff; and 60% and 99% in sex workers. CONCLUSION: These results confirm a higher prevalence of HSV infection than estimated, especially in high risk groups in Turkey. The high prevalence of HSV infection underlines the need for education among these populations.     

Prevalence of serum antibodies to herpes simplex virus types 1 and 2: application of an ELISA technique to 100 cases of anogenital herpes

Sera of 100 patients affected by anogenital herpes were tested by an enzyme-linked immunosorbent assay (ELISA) technique using partially purified antigens obtained by extraction from the nuclei of infected Vero cells. Herpes simplex virus type 1 (HSV-1) was isolated from the anogenital lesions of 17 patients and herpes simplex virus type 2 (HSV-2) from 83 patients. The relative proportions of antibody of the IgG class to HSV-1 and HSV-2 were determined and their ratio (R) was calculated, except for 23 patients for whom the corrected optical density (COD) obtained for HSV-1 or HSV-2 antibody was less than the lower value limit of 0.025. A predominance of HSV-2 antibody (R less than 1) was found in 40 patients and was uniformly associated with isolation of HSV-2, whereas a predominance of HSV-1 antibody (R greater than 1) in 37 patients was found in the presence of infection with HSV-1 in 11 (30%) and with HSV-2 in 26 (70%) patients. This study also confirms the association of a higher frequency of recurrences with HSV-2: among the 55 patients with recurrent herpes, those from whom HSV-2 was isolated had a history of more recurrences than those infected with HSV-1 (P less than 0.05; Mann and Whitney's nonparametric test). No correlation between the number of recurrences and the level of HSV-2 antibody was found.     

Changing epidemiology of genital herpes simplex virus infection in Melbourne, Australia, between 1980 and 2003

OBJECTIVE: To investigate changes in the proportions of patients infected with genital herpes simplex virus (HSV) types 1 and 2 from 1980 to 2003 in Melbourne, Australia. METHODS: A total of 25 372 patients were studied retrospectively. The proportions of HSV-1 and HSV-2 detected in these individuals were analysed by age, sex, and genital site. RESULTS: In 1980 only 15.8% of HSV positive genital specimens were HSV-1 compared to 34.9% in 2003. In 2003 HSV-1 was detected in 77% of patients aged less than 20 years. Females were more likely to be infected with HSV-1, although the rate of increased detection was more pronounced in males. Except for females over the age of 40, the trend for the increase in HSV-1 was detected in all age groups. No specific genital site in either sex was associated with the increase. CONCLUSIONS: The proportion of genital HSV-1 has increased in Australian patients, although HSV-2 is still the most common cause of genital infection. Confirmation of HSV type is necessary for optimal patient management.     

Inapparent genital herpes simplex infection in women attending a venereal disease clinic

The purpose of this study was to determine the prevalence of asymptomatic genital infection with herpes simplex virus in women attending a venereal disease clinic in Puerto Rico. Genital samples were obtained from 123 consecutively enrolled patients. Vero cells were used for viral isolation; isolates demonstrating cytopathic effect were stored at -70 C and were typed by use of monoclonal antibodies. Herpes simplex virus was isolated from six patients, three of whom were free of any possible complaint that might be associated with a genital herpes virus infection. One patient was diagnosed as having herpetic cervicitis, and the remaining two were clinically diagnosed as well as laboratory confirmed cases of genital herpes. Virus isolated from all six women was identified as herpes simplex virus type 2. Thus the prevalence of laboratory confirmed genital herpes infection in women attending this clinic was 4.9% (6/123). Inapparent virus infection was detected in 2.5% (3/120) of the patients.     

Herpes simplex virus type 2 (HSV-2) Western blot confirmatory testing among men testing positive for HSV-2 using the focus enzyme-linked immunosorbent assay in a sexually transmitted disease clinic

OBJECTIVE: The objective of this study was to define the positive predictive value (PPV) of the Focus herpes simplex virus type 2 (HSV-2) enzyme-linked immunosorbent assay (ELISA) in a low HSV-2 prevalence population and to develop a new test interpretation algorithm. METHODS: HSV-2 Western blots were performed on sera from male sexually transmitted disease clinic patients testing HSV-2 ELISA-positive and used to define a new class of indeterminate HSV-2 ELISA result. HSV-2 Western blots were then prospectively performed on sequential sera with indeterminate HSV-2 ELISAs. RESULTS: Ninety-one (84%) of 108 HSV-2 ELISA-positive sera tested HSV-2 Western blot-positive. Western blot positivity was more common in men without herpes simplex virus type 1 (HSV-1) antibody than in those with HSV-1 antibody (93% vs 76%, P = 0.02) and in men with a history or clinical evidence of genital lesions (88% vs 80%, P = 0.30). Selectively raising the ELISA index value defining HSV-2 positivity from >1.1 to >or=3.0 either among HSV-1-positive men or among those without a history or clinical evidence of genital lesions increased the PPV to >or=93%. Prospective evaluation of an algorithm incorporating HSV-1 serostatus found that 11 of 70 persons with indeterminate HSV-2 ELISAs were Western blot-positive. CONCLUSIONS: Clinicians should consider selectively using a higher index value to define Focus ELISA HSV-2 positivity based on either HSV-1 serostatus or clinical circumstances.     

One-day regimen of valacyclovir for treatment of recurrent genital herpes simplex virus 2 infection

OBJECTIVES: To evaluate the efficacy of a 1-day course of valacyclovir in reducing the duration and severity of genital herpes recurrences and to measure the frequency of viral shedding episodes subsequent to antiviral therapy. STUDY DESIGN: In an open-label pilot study, patients with recurrent genital herpes simplex virus 2 (HSV-2) infection were given a 1-day course of valacyclovir (2000 mg given by mouth twice daily) to be taken at the first sign of recurrence or prodrome. Participants maintained diaries of signs and symptoms and collected genital swabs for viral culture while lesions persisted and HSV DNA PCR for 14 days after initiating treatment. RESULTS: Ninety (78%; 41 men, 49 women) of the 115 enrolled persons experienced either a lesional recurrence or prodrome. Seventy-seven (86%) participants developed lesions; 4 (5%) participants experienced a second lesional recurrence during the 14-day study period. The median lesion duration was 5 days, episode duration was 5 days, and pain duration was 3 days. Viral shedding was detected in 60 persons by PCR and 31 persons by culture. Shedding detected by culture lasted for a median of 2 days, and shedding detected by PCR lasted for a median of 3 days. Of 60 participants with viral shedding, 14 (23%) had an additional shedding episode after their initial lesion healed, lasting for a median of 2 days. CONCLUSIONS: A 1-day course of valacyclovir may be a convenient treatment for recurrent genital herpes and comparative trials are warranted.