Risk factors for incident herpes simplex type 2 virus infection among women attending a sexually transmitted disease clinic

Protective Mechanisms of Vaginal Lactobacilli against Sexually Transmitted Viral Infections

The healthy cervicovaginal microbiota is dominated by various Lactobacillus species, which support a condition of eubiosis. Among their many functions, vaginal lactobacilli contribute to the maintenance of an acidic pH, produce antimicrobial compounds, and modulate the host immune response to protect against vaginal bacterial and fungal infections. Increasing evidence suggests that these beneficial bacteria may also confer protection against sexually transmitted infections (STIs) caused by viruses such as human papillomavirus (HPV), human immunodeficiency virus (HIV) and herpes simplex virus (HSV). Viral STIs pose a substantial public health burden globally, causing a range of infectious diseases with potentially severe consequences. Understanding the molecular mechanisms by which lactobacilli exert their protective effects against viral STIs is paramount for the development of novel preventive and therapeutic strategies. This review aims to provide more recent insights into the intricate interactions between lactobacilli and viral STIs, exploring their impact on the vaginal microenvironment, host immune response, viral infectivity and pathogenesis, and highlighting their potential implications for public health interventions and clinical management strategies.

Association of Recent Bacterial Vaginosis With Acquisition of Mycoplasma genitalium

We assessed the association between recent bacterial vaginosis (BV) and incident Mycoplasma genitalium, a sexually transmitted bacterium associated with adverse female reproductive health outcomes. Female sex workers in Mombasa, Kenya, completed a monthly sexual behavior interview and clinical examination. During February 2005-February 2006, vaginal fluid specimens collected from women every other month were tested for M. genitalium by nucleic acid amplification testing. Vaginal microbiota were assessed monthly and categorized by Nugent score (0-3 = normal microbiota, 4-6 = intermediate microbiota disruption, and 7-10 = BV). A discrete failure time analysis for multiple events using logistic regression was employed to estimate the odds of incident M. genitalium infection at follow-up visits among women with BV (vs. normal microbiota) at the preceding visit. Among the 280 women, 54.3% were positive for human immunodeficiency virus. At baseline, 16.1% had prevalent M. genitalium infection and 40.4% had prevalent BV. There were 59 incident M. genitalium infections among 50 women, for an incidence rate of 34.6 cases per 100 person-years. Following adjustment for age, human immunodeficiency virus status, and time, prior BV was associated with a 3.5-fold increase in odds of incident M. genitalium (adjusted odds ratio = 3.49, 95% confidence interval: 1.86, 6.56). This strong association suggests that BV may enhance susceptibility to M. genitalium infection.

Is the role of human female reproductive tract microbiota underestimated?

An issue that is currently undergoing extensive study is the influence of human vaginal microbiota (VMB) on the health status of women and their neonates. Healthy women are mainly colonised with lactobacilli such as Lactobacillus crispatus, Lactobacillus jensenii, and Lactobacillus iners; however, other bacteria may be elements of the VMB, particularly in women with bacterial vaginosis. The implementation of culture-independent molecular methods in VMB characterisation, especially next-generation sequencing, have provided new information regarding bacterial diversity in the vagina, revealing a large number of novel, fastidious, and/or uncultivated bacterial species. These molecular studies have contributed new insights regarding the role of bacterial community composition. In this study, we discuss recent findings regarding the reproductive tract microbiome. Not only bacteria but also viruses and fungi constitute important components of the reproductive tract microbiome. We focus on aspects related to the impact of the maternal microbiome on foetal development, as well as the establishment of the neonatal microbiomes, including the placenta microbiome, and the haematogenous source of intrauterine infection. We also discuss whether the role of the vaginal microbiome is currently understood and appreciated.

Prevalence of Herpes Simplex Virus 2 (HSV-2) infection and associated risk factors in a cohort of HIV negative women in Durban, South Africa

Background

Herpes Simplex Virus 2 (HSV-2) is one of the most common sexually transmitted infections (STIs) worldwide and is a risk factor for the acquisition and transmission of other STIs, including HIV. We determined the prevalence and predictors of HSV-2 infection among women screened for a HIV prevention trial in Durban, South Africa. Univariate and multivariate logistic and Cox regression models were used to determine the correlates and predictors of HSV-2 infection at enrolment and seroconversion during the study respectively.

Results

Prevalence of HSV-2 at screening was 65% and crude incidence was 22.3 per 100 person-years (PY) (95% CI 20.4–24.3). The HIV seroconversion was significantly higher among those testing positive for HSV-2 at baseline compared to women who were negative [8.7 per 100 person years (PY) versus 5.2 per 100 PY; (p < 0.001)]. In univariate analysis, age was determined to be the most significant predictor for HSV-2 diagnosis, while co-infection with syphilis was also a significant predictor, while age and co-infection with syphilis remained the two most significant predictors of having HSV-2 in multivariate analysis at baseline. Consistent with these results, along with HIV seroconversion, age was also identified as a significant predictor for incidence of HSV-2.

Conclusion

Given the unacceptably high prevalence and incidence rates of HSV-2 infection reported here, HSV-2 and general STI education needs to be reinforced in these communities, with a focus on condom education for prevention. HSV-2 has emerged as the most prevalent STI which is most often asymptomatic and unrecognized, and which increases women’s risk of acquiring other STIs, including HIV.

Effect of Condom Use on Per-act HSV-2 Transmission Risk in HIV-1, HSV-2-discordant Couples

BACKGROUND

The efficacy of condoms for protection against transmission of herpes simplex virus type 2 (HSV-2) has been examined in a variety of populations with different effect measures. Often the efficacy has been assessed as change in hazard of transmission with consistent vs inconsistent use, independent of the number of acts. Condom efficacy has not previously measured on a per-act basis.

METHODS

We examined the per-act HSV-2 transmission rates with and without condom use among 911 African HSV-2 and human immunodeficiency virus type 1 (HIV-1) serodiscordant couples followed for an average of 18 months in an HIV prevention study. Infectivity models were used to associate the log10 probability of HSV-2 transmission over monthly risk periods with reported numbers of protected and unprotected sex acts. Condom efficacy was computed as the proportionate reduction in transmission risk for protected relative to unprotected sex acts.

RESULTS

Transmission of HSV-2 occurred in 68 couples, including 17 with susceptible women and 51 with susceptible men. The highest rate of transmission was from men to women: 28.5 transmissions per 1000 unprotected sex acts. We found that condoms were differentially protective against HSV-2 transmission by sex; condom use reduced per-act risk of transmission from men to women by 96% (P < .001) and marginally from women to men by 65% (P = .060).

CONCLUSIONS

Condoms are recommended as an effective preventive method for heterosexual transmission of HSV-2.

Lactobacillus species as biomarkers and agents that can promote various aspects of vaginal health

The human body is colonized by a vast number of microorganisms collectively referred to as the human microbiota. One of the main microbiota body sites is the female genital tract, commonly dominated by Lactobacillus spp., in approximately 70% of women. Each individual species can constitute approximately 99% of the ribotypes observed in any individual woman. The most frequently isolated species are Lactobacillus crispatus, Lactobacillus gasseri, Lactobacillus jensenii and Lactobacillus iners. Residing at the port of entry of bacterial and viral pathogens, the vaginal Lactobacillus species can create a barrier against pathogen invasion since mainly products of their metabolism secreted in the cervicovaginal fluid can play an important role in the inhibition of bacterial and viral infections. Therefore, a Lactobacillus-dominated microbiota appears to be a good biomarker for a healthy vaginal ecosystem. This balance can be rapidly altered during processes such as menstruation, sexual activity, pregnancy and various infections. An abnormal vaginal microbiota is characterized by an increased diversity of microbial species, leading to a condition known as bacterial vaginosis. Information on the vaginal microbiota can be gathered from the analysis of cervicovaginal fluid, by using the Nugent scoring or the Amsel's criteria, or at the molecular level by investigating the number and type of Lactobacillus species. However, when translating this to the clinical setting, it should be noted that the absence of a Lactobacillus-dominated microbiota does not appear to directly imply a diseased condition or dysbiosis. Nevertheless, the widely documented beneficial role of vaginal Lactobacillus species demonstrates the potential of data on the composition and activity of lactobacilli as biomarkers for vaginal health. The substantiation and further validation of such biomarkers will allow the design of better targeted probiotic strategies.

Randomized Trial of Periodic Presumptive Treatment With High-Dose Intravaginal Metronidazole and Miconazole to Prevent Vaginal Infections in HIV-negative Women

BACKGROUND

Vaginal infections are common, frequently recur, and may increase women's risk for sexually transmitted infections (STIs). We tested the efficacy of a novel regimen to prevent recurrent vaginal infections.

METHODS

Human immunodeficiency virus (HIV)-negative women 18-45 years old with 1 or more vaginal infections, including bacterial vaginosis (BV), vulvovaginal candidiasis (VVC), or Trichomonas vaginalis (TV), were randomly assigned to receive vaginal suppositories containing metronidazole 750 mg plus miconazole 200 mg or matching placebo for 5 consecutive nights each month for 12 months. Primary endpoints, evaluated every 2 months, were BV (Gram stain) and VVC (positive wet mount and culture).

RESULTS

Participants (N = 234) were randomly assigned to the intervention (N = 118) or placebo (N = 116) arm. Two hundred seventeen (93%) women completed an end-of-study evaluation. The intervention reduced the proportion of visits with BV compared to placebo (21.2% vs 32.5%; relative risk [RR] 0.65, 95% confidence interval [CI] .48-.87). In contrast, the proportion of visits with VVC was similar in the intervention (10.4%) versus placebo (11.3%) arms (RR 0.92, 95% CI .62-1.37).

CONCLUSIONS

Monthly treatment with intravaginal metronidazole plus miconazole reduced the proportion of visits with BV during 12 months of follow-up. Further study will be important to determine whether this intervention can reduce women's risk of STIs.

The vaginal microbiota and susceptibility to HIV

There is some evidence that the risk of HIV infection per heterosexual act is higher in low-income countries than in high-income countries. We hypothesize that variations in per sex-act transmission probability of HIV may in part be attributed to differences in the composition and function of the vaginal microbiota between different populations. This paper presents data that are in support of this hypothesis. Experimental and clinical studies have provided evidence that the normal vaginal microbiota plays a protective role against acquisition of HIV and other sexually transmitted infections. Epidemiological studies have convincingly shown that disturbances of the vaginal microbiome, namely intermediate flora and bacterial vaginosis, increase the risk of acquisition of HIV infection. A review of the literature found large differences in prevalence of bacterial vaginosis between different populations, with the highest prevalence rates found in black populations. Possible explanations for these differences are presented including data suggesting that there are ethnic differences in the composition of the normal vaginal microbiota. Lastly, interventions are discussed to restore and maintain a healthy vaginal environment.

Treatment of bacterial vaginosis: what we have and what we miss

INTRODUCTION

The disturbing, foul-smelling discharge of bacterial vaginosis (BV) is a nuisance to women. Treatment possibilities for BV are limited and only achieve complete cure in 65 to 85% of cases. In most women, the condition relapses within weeks to months after treatment.

AREAS COVERED

In search of new therapeutic actions to cure, prevent or delay recurrences of BV, PubMed and web of science were searched for papers with i) decent study layout, ii) proper statistics, iii) comparison group (placebo or standard treatment) and iv) language English, French, Dutch or German. The following keywords were used: bacterial vaginosis and treatment or management or therapy or prophylaxis or prevention. Results were grouped in treatment categories and were discussed.

EXPERT OPINION

Clindamycin and metronidazole are the standard drugs for BV. As other antibiotic and acidifying treatments are progressively being studied, like tinidazole, rifaximin, nitrofuran, dequalinium chloride, vitamin C and lactic acid, more options have become available for switching therapy, combining therapies and long-term prophylactic use to prevent recurrences. Further studies are needed. Also, adjuvant therapy with probiotics may have a significant role in improving efficacy and in preventing recurrences. However, it is unlikely that probiotics will replace antibiotherapy.

The epidemiology of HIV and HSV-2 infections among women participating in microbicide and vaccine feasibility studies in Northern Tanzania

OBJECTIVES

To prepare for future HIV prevention trials, we conducted prospective cohort studies among women working in food and recreational facilities in northern Tanzania. We examined the prevalence and incidence of HIV and HSV-2, and associated risk factors.

METHODS

Women aged 18-44 years working in food and recreational facilities were screened to determine their eligibility for the studies. Between 2008-2010, HIV-negative women were enrolled and followed for 12 months. At enrolment and 3-monthly, we collected socio-demographic and behavioural data, and performed clinical examinations for collection of biological specimens that were tested for reproductive tract infections. Risk factors for HIV and HSV-2 incidence were investigated using Poisson regression models.

RESULTS

We screened 2,229 and enrolled 1,378 women. The median age was 27 years (interquartile range, IQR 22, 33), and median duration working at current facility was 2 years. The prevalences of HIV at screening and HSV-2 at enrolment were 16% and 67%, respectively. Attendance at the 12-month visit was 86%. HIV and HSV-2 incidence rates were 3.7 (95% confidence interval, CI: 2.8,5.1) and 28.6 (95% CI: 23.5,35.0)/100 person-years, respectively. Women who were separated, divorced, or widowed were at increased risk of HIV (adjusted incidence rate ratio, aRR = 6.63; 95% CI: 1.97,22.2) and HSV-2 (aRR = 2.00; 95% CI: 1.15,3.47) compared with married women. Women reporting ≥3 partners in the past 3 months were at higher HIV risk compared with women with 0-1 partner (aRR = 4.75; 95% CI: 2.10,10.8), while those who had reached secondary education or above were at lower risk of HSV-2 compared with women with incomplete primary education (aRR = 0.42; 95% CI: 0.22,0.82).

CONCLUSIONS

HIV and HSV-2 rates remain substantially higher in this cohort than in the general population, indicating urgent need for effective interventions. These studies demonstrate the feasibility of conducting trials to test new interventions in this highly-mobile population.

Epidemiology, clinical presentation, and antibody response to primary infection with herpes simplex virus type 1 and type 2 in young women

BACKGROUND

Herpes simplex virus infections type 1 (HSV-1) and type 2 (HSV-2) are common, but the epidemiology of HSV disease is changing.

METHODS

HSV-seronegative women, aged 18-30 years, who were in the control arm of the HERPEVAC Trial for Women were followed for 20 months for primary HSV infections.

RESULTS

Of the 3438 evaluable participants, 183 became infected with HSV: 127 (3.7%) with HSV-1 and 56 (1.6%) with HSV-2. The rate of infection for HSV-1 (2.5 per 100 person-years) was more than twice that for HSV-2 (1.1 per 100 person-years). Most infections (74% of HSV-1 and 63% of HSV-2) occurred without recognized signs or symptoms of herpes disease. The HSV-2 infection rate was 2.6 times higher in non-Hispanic black participants than in Hispanics and 5.5 times higher than in non-Hispanic whites (P < .001), while the HSV-1 infection rate was 1.7 times higher in non-Hispanic whites than non-Hispanic blacks. Younger participants (18-22 years) were more likely to acquire HSV-1 infections and less likely to develop recognized disease than older participants. Overall, 84% of recognized disease cases were genital. No differences were noted in the clinical manifestations of genital HSV-1 vs genital HSV-2 disease. The clinicians' assessment that cases were caused by HSV was good when they assessed cases as clinically confirmed or unlikely (validated in 83% and 100% of cases, respectively).

CONCLUSIONS

HSV-1 is now more common than HSV-2 as a cause of oral and genital mucosal infections in young women, but there are important age and race differences.

Case-crossover analysis of condom use and herpes simplex virus type 2 acquisition

BACKGROUND

Although growing evidence suggests that condoms offer moderate protection against herpes simplex virus type 2 (HSV-2), inability to control for unknown or unmeasured confounders associated with sexual activity may reduce the accuracy of the estimates. The case-crossover design offers increased control of individual-level confounders, and was thus used with the aim of producing a more accurate estimate of the effect of condom use on HSV-2 acquisition.

METHODS

Data were pooled from 6 prospective studies that measured HSV-2 status at enrollment and over follow-up, and included periodic self-reported condom use and sexual activity. Sexual activity contemporaneous with acquisition was assigned to a case period; earlier sexual activity was assigned to a control period. Conditional logistic regression was used to assess differences in behavior during the case and control periods.

RESULTS

One hundred ninety-one eligible participants acquired HSV-2 during follow-up. This approach detected a 3.6% increase in the odds of HSV-2 acquisition with each unprotected act (odds ratio = 1.036; 95% confidence interval: 1.021-1.052), but no increase in the odds of acquisition associated with protected acts (odds ratio = 1.008; 95% confidence interval: 0.987-1.030).

CONCLUSIONS

This analysis suggests that condoms offer significant protection against HSV-2 transmission.

Incidence, prevalence, and epidemiology of herpes simplex virus-2 in HIV-1-positive and HIV-1-negative adolescents

BACKGROUND

Several studies have assessed risk factors associated with herpes simplex virus-2 (HSV-2) prevalence in adults; however, few have focused on HSV-2 incidence, particularly in adolescents. The objective of this study was to determine HSV-2 prevalence and incidence and associated risk factors in a HIV-1-positive and at risk HIV-1-negative adolescent population.

METHODS

Sera were tested for HSV-2 antibodies in 518 adolescents in the Reaching for Excellence in Adolescent Care and Health cohort at baseline and again at the final follow-up visit. Prevalence at baseline and incidence (per person years) of HSV-2 infection were calculated. Furthermore, among HIV-1-positive individuals, a subgroup analysis was performed to assess risk factors for HSV-2 infection. Conditional logistic regression was used to estimate odds ratios and P values for associations between CD4+ T-cell (CD4+) count, HIV-1 viral load (VL), and HSV-2 acquisition, adjusting for antiretroviral therapy use, other sexually transmitted infections, gender, race, and number of sexual partners.

RESULTS

At baseline, 179 (35%) subjects were HSV-2 positive, with an additional 47 (16%) new cases being identified during a median follow-up time of 1.95 years and an incidence rate of 7.35 cases per 100 person years. Several risk factors were associated with HSV-2 prevalence (being female, non-Hispanic, uncertainty of sexual preference, and HIV-1 positive) and incidence (using drugs, alcohol, and number of new sexual partners). Among HIV-1 positives, an increase in CD4+ count by 50 cell/mm(3) (odds ratio, 1.17; 95% CI, 1.04-1.31, P = 0.008) was associated with HSV-2 acquisition.

CONCLUSIONS

The high prevalence and incidence of HSV-2 infection among adolescents, compared with the general population at this age group suggests a critical need for screening and preventive programs among this targeted group.

National estimates of seroincidence and seroprevalence for herpes simplex virus type 1 and type 2 among US military adults aged 18 to 29 years

BACKGROUND

While population-based seroprevalence studies of herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2) are widespread, seroincidence studies are largely limited to select or high-risk populations. The US military offers a potential population to derive national seroincidence rate estimates for young adults (ages 18-29).

METHODS

We used banked, longitudinal serum specimens collected in a cohort of 1094 military personnel aged 18 to 30 years who served between 1989 and 2005 to estimate national HSV-1 and HSV-2 seroincidence and seroprevalence for the young, adult military population, weighted according to the US Census. Serum was tested with indirect ELISA (enzyme-linked immunosorbent assay).

RESULTS

Estimated national seroincidence rates for the US young, adult military population were 9.1 per 100 person-years (95% confidence interval: 4.6-13.5) for HSV-1 and 6.2 (95% confidence interval: 3.1-9.3) for HSV-2. Female sex and black race were associated with significantly higher HSV-2 seroconversion rates. Our estimated HSV1/2 seroprevalences were comparable to US national data provided by National Health and Nutrition Examination Surveys' serosurveys except for non-Hispanic blacks and Hispanics.

CONCLUSION

Although these US 2000 Census-weighted estimates of HSV-1 and HSV-2 seroincidence apply only to young, military adults, they nonetheless supply, to our knowledge, the only national figures that might be used to predict US national HSV1/2 seroincidence in young adults. Thus, we believe that our findings in this military population can be used to inform the planning of HSV-1 and 2 prevention measures in the general, young-adult US population.

European (IUSTI/WHO) guideline on the management of vaginal discharge, 2011

Three common infections are associated with vaginal discharge: bacterial vaginosis, trichomoniasis and candidiasis, of which trichomoniasis is a sexually transmitted infection (STI). This guideline covers the presentation and clinical findings of these infections and outlines the differential diagnoses. Recommendations for investigation and management based on currently available evidence are made, including the management of persistent and recurrent infections.

Incidence of herpes simplex virus type 2 in young reproductive age women in Mysore, India

CONTEXT

There are sparse data on herpes simplex virus type 2 (HSV-2) infection in India. HSV-2 is one of the most common sexually transmitted infections and the primary cause of genital ulcer disease worldwide.

AIM

The aim of this study is to describe the incidence of HSV-2 infection among young reproductive age women in Mysore, India.

SETTING AND DESIGN

Between October 2005 and April 2006, 898 women were enrolled into a prospective cohort study in Mysore, India, and followed quarterly for 6 months.

MATERIALS AND METHODS

An interviewer administered questionnaire was used to collect demographic and social risk factors, and physical examination was conducted for collection of biological specimens to screen for reproductive tract infections at each visit. Serologic testing was conducted for the presence of HSV-2 antibodies using HerpeSelect HSV-2 enzyme-linked immunosorbent assay.

STATISTICAL ANALYSIS USED

Data were analyzed using R. Incidence density rates were calculated using Poisson distributions with person-time of follow-up as denominator. Person-time was calculated as time from enrollment until time of first positive HSV-2 test.

RESULTS

There were 107 women with HSV-2 antibodies leaving 700 women with negative results at enrollment. The analysis included 696 out of which, there were 36 HSV-2 seroconversions during the study period. The study cohort accumulated roughly 348 woman-years of follow-up, yielding an HSV-2 acquisition rate of 10.4 cases/100 woman-years. All detected infections were asymptomatic.

CONCLUSIONS

HSV-2 incidence is moderate in this community sample of young reproductive age monogamous women. More research is needed to establish incidence estimates in different Indian settings.

Diagnosis and management of bacterial vaginosis and other types of abnormal vaginal bacterial flora: a review

Bacterial vaginosis (BV) is a common cause of abnormal vaginal discharge. It is characterised by an overgrowth of predominantly anaerobic organisms (Gardnerella vaginalis, Prevotella spp., Peptostreptocci, Mobiluncus spp.) in the vagina leading to a replacement of lactobacilli and an increase in vaginal pH. BV can arise and remit spontaneously, but often presents as a chronic or recurrent disease. BV is found most often in women of childbearing age, but may also be encountered in menopausal women, and is rather rare in children. The clinical and microscopic features and diagnosis of BV are herein reviewed, and antibiotic and non-antibiotic treatment approaches discussed.

TARGET AUDIENCE

Obstetricians & Gynecologists, Family Physicians.

LEARNING OBJECTIVES

After completion of this educational activity, the participant should be better able to analyze bacterial vaginosis clinically, formulate an oral antibiotic treatment regimen for bacterial vaginosis and use vaginal treatments for bacterial vaginosis.

Socio-demographic and behavioral correlates of herpes simplex virus type 1 and 2 infections and co-infections among adults in the USA

OBJECTIVES

Although herpes simplex virus (HSV)-1 and HSV-2 may co-exist and interact, some epidemiologic features including geographical distribution, secular trends, route of transmission, and established risk factors may distinguish these HSV sub-types. With recent data indicating a link between genital herpes and either strain, a re-evaluation of risk factors for HSV-1/HSV-2 infection and co-infection is needed.

METHODS

We used the 1999-2004 National Health and Nutrition Examination Study (NHANES) data and logistic regression modeling to identify socio-demographic and behavioral risk factors that can independently predict HSV-1/HSV-2 infection and co-infection.

RESULTS

Approximately 48% were positive for HSV-1 alone, 7% were positive for HSV-2 alone and 12% were co-infected with HSV-1 and HSV-2. History of genital herpes was found in individuals infected with either or both HSV sub-types. Whereas age, sex, race, and level of education independently predicted all three outcomes, lifetime sexual activity as well as use of tobacco products and recreational drugs mainly correlated with HSV-2 infection and HSV-1/HSV-2 co-infection. Lifetime use of alcohol was not consistently associated with HSV-1/HSV-2 infection and co-infection.

CONCLUSIONS

Sexual activity played an important role for HSV-2 and was potentially important for HSV-1, with implications for healthcare practice and vaccine development.

Vaginal microbiota and the use of probiotics

The human vagina is inhabited by a range of microbes from a pool of over 50 species. Lactobacilli are the most common, particularly in healthy women. The microbiota can change composition rapidly, for reasons that are not fully clear. This can lead to infection or to a state in which organisms with pathogenic potential coexist with other commensals. The most common urogenital infection in premenopausal women is bacterial vaginosis (BV), a condition characterized by a depletion of lactobacilli population and the presence of Gram-negative anaerobes, or in some cases Gram-positive cocci, and aerobic pathogens. Treatment of BV traditionally involves the antibiotics metronidazole or clindamycin, however, the recurrence rate remains high, and this treatment is not designed to restore the lactobacilli. In vitro studies have shown that Lactobacillus strains can disrupt BV and yeast biofilms and inhibit the growth of urogenital pathogens. The use of probiotics to populate the vagina and prevent or treat infection has been considered for some time, but only quite recently have data emerged to show efficacy, including supplementation of antimicrobial treatment to improve cure rates and prevent recurrences.