Cost-Effectiveness Analysis of Annual Trichomonas vaginalis Screening and Treatment in HIV-Positive Women to Prevent HIV Transmission

Declining Prevalence of Trichomonas vaginalis Diagnosed by Wet Mount in a Cohort of U.S. Women With and Without HIV

Background: Women living with HIV (WLWH) are often coinfected with Trichomonas vaginalis (TV), and annual screening is recommended. Our goal was to assess differences in TV prevalence at study entry and over time in enrollment cohorts of the Women's Interagency HIV Study. Methods: In a multisite study, TV was diagnosed by wet mount microscopy. Prevalence was determined across four enrollment waves: 1994-1995, 2001-2002, 2011-2012, and 2013-2015. Generalized estimating equation multivariable logistic regression models assessed changes in visit prevalence across waves after controlling for HIV disease severity and other risks. Results: At 63,824 person-visits (3,508 WLWH and 1,262 women without HIV), TV was diagnosed by wet mount at 1979 visits (3.1%). After multivariable adjustment, HIV status was not associated with TV detection, which was more common among younger women, women with multiple partners, and irregular condom use. All enrollment waves showed a decline in TV detection over time, although p-value for trend did not reach significance for most recent waves. To explore the potential utility of screening among WLWH, we assessed rates of TV detection among women without appreciable vaginal discharge on examination. Initial TV prevalence among asymptomatic women was 3.5%, and prevalence decreased to 0.5%-1% in the most recent wave (2013-2015) (p-trend <0.0001). Conclusions: In this cohort, TV rates are low among WLWH, and HIV does not increase TV risk. Screening may benefit newly diagnosed WLWH, women with risk factors, or those receiving care sporadically but is unlikely to further reduce the low rate of TV among women in care, especially older women without multiple partners. The clinical trials registration number for WIHS is NCT00000797.

The Cost-Effectiveness of HIV/STI Prevention in High-Income Countries with Concentrated Epidemic Settings: A Scoping Review

The purpose of this scoping review is to establish the state of the art on economic evaluations in the field of HIV/STI prevention in high-income countries with concentrated epidemic settings and to assess what we know about the cost-effectiveness of different measures. We reviewed economic evaluations of HIV/STI prevention measures published in the Web of Science and Cost-Effectiveness Registry databases. We included a total of 157 studies focusing on structural, behavioural, and biomedical interventions, covering a variety of contexts, target populations and approaches. The majority of studies are based on mathematical modelling and demonstrate that the preventive measures under scrutiny are cost-effective. Interventions targeted at high-risk populations yield the most favourable results. The generalisability and transferability of the study results are limited due to the heterogeneity of the populations, settings and methods involved. Furthermore, the results depend heavily on modelling assumptions. Since evidence is unequally distributed, we discuss implications for future research.

Diagnosis and Management of Trichomonas vaginalis: Summary of Evidence Reviewed for the 2021 Centers for Disease Control and Prevention Sexually Transmitted Infections Treatment Guidelines

Trichomonas vaginalis is likely the most prevalent nonviral sexually transmitted infection, affecting an estimated 3.7 million women and men in the United States. Health disparities are prominent in the epidemiology of trichomoniasis, as African Americans are >4 times more likely to be infected than persons of other races. Since publication of the 2015 Centers for Disease Control and Prevention sexually transmitted diseases treatment guidelines, additional data have bolstered the importance of T. vaginalis infection sequelae in women, including increased risk of human immunodeficiency virus (HIV) acquisition, cervical cancer, preterm birth, and other adverse pregnancy outcomes. Less is known about the clinical significance of infection in men. Newly available diagnostic methods, including point-of-care assays and multiple nucleic acid amplification tests, can be performed on a variety of genital specimens in women and men, including urine, allowing more accurate and convenient testing and screening of those at risk for infection. Repeat and persistent infections are common in women; thus, rescreening at 3 months after treatment is recommended. In vitro antibiotic resistance to 5-nitroimidazole in T. vaginalis remains low (4.3%) but should be monitored. High rates of T. vaginalis among sexual partners of infected persons suggest a role for expedited partner treatment. A randomized controlled trial in HIV-uninfected women demonstrated that multidose metronidazole 500 mg twice daily for 7 days reduced the proportion of women with Trichomonas infection at 1 month test of cure compared with women receiving single-dose therapy (2 g). The 2-g single-dose oral metronidazole regimen remains the preferred treatment in men.

Reduced Trichomonas vaginalis viability in mice pretreated with parasite DNA

Trichomonas vaginalis is an extracellular parasite that colonizes the human urogenital tract leading to trichomoniasis, the most common sexually-transmitted non-viral disease worldwide. The immune response plays a critical role in the host defense against this parasite. Trichomonas' DNA contains unmethylated CpG motifs (CpGDNA) that in other microorganisms act as modulators of the immune response. However, the molecular mechanisms responsible for CpGDNA immune modulation are still unclear. As macrophages participate in the first line of defense against infection, we investigated the type of immune response of murine macrophages to T. vaginalis DNA (TvDNA). We observed high expression of the proinflammatory cytokines IL-6 and IL-12p40 in macrophages stimulated with TvDNA. In contrast, the anti-inflammatory response, assessed by IL-10 and IL-13 mRNA expression was delayed. This suggests that the immune response induced by TvDNA is modulated through cytokine production, mediated partly by NADPH-oxidase activity, as TvDNA induced reactive species of oxygen production and a rounded morphology in macrophages indicative of an M1 phenotype. Furthermore, infected mice pretreated with TvDNA displayed persistent vulvar inflammation and decreased parasite viability consistent with higher proinflammatory cytokine levels during infection compared to untreated mice. Overall, our findings suggest that TvDNA pretreatment modulates the immune response favouring parasite elimination.

Profile of the triplex assay for detection of chlamydia, gonorrhea and trichomonas using the BD MAX™ System

INTRODUCTION

Chlamydia, gonorrhea and trichomonas are the most common curable STI. improved access to testing could reduce infection rates and prevent sequelae. nucleic acid amplification tests are the recommend class of diagnostic assay for these infections which are often asymptomatic. Areas covered: A description of the BD MAX™ System (MAX) and the BD MAX CT/GC/TV assay is provided along with data from a large US clinical trial. The capacity of the system for other tests and for lab developed assays is also described. Expert commentary: The CT/GC/TV assay on the MAX is a triplex PCR assay suitable for use with female urine and vaginal or endocervical swab samples. Male urine can be tested by ordering the CT/GC results but has not yet been evaluated for trichomonas. The assay performance characteristics are similar to those of assays run on high-throughput platforms with sensitivity ≥91.5% and specificity ≥98.6% for all analytes. Screening with the CT/GC/TV assay can be combined with testing for vaginitis which would provide a greater depth of coverage for common co-infections. The throughput is moderate (1-48 samples per 8-hour shift) but the menu includes assays beyond STI pathogens making this a suitable platform for moderate volume laboratories.

Trichomonas vaginalis and Human Immunodeficiency Virus Coinfection Among Women Under Community Supervision: A Call for Expanded T. vaginalis Screening

BACKGROUND

The United States has a large community supervision population, a growing number of whom are women. Trichomonas vaginalis infection is strongly associated with an increased risk of human immunodeficiency virus (HIV) acquisition and transmission, particularly among women, but there is a paucity of research on HIV and T. vaginalis co-infection among women under community supervision.

METHODS

This article examines the prevalence of T. vaginalis infection and T. vaginalis and HIV coinfection at baseline among women under community supervision in New York City. It also examines the 12-month outcomes of women treated for T. vaginalis. Women received biological tests for HIV and T. vaginalis at baseline and 12 months follow-up.

RESULTS

Of the 333 women tested for sexually transmitted infections, 77 women (23.1%) tested positive for T. vaginalis at baseline and 44 (13.3%) were HIV positive. Human immunodeficiency virus-positive women had significantly higher rates of T. vaginalis infection than HIV-negative women (36.4% vs 21.3%, P ≤ 0.05). Sixteen women (4.8%) were coinfected with T. vaginalis and HIV. Of the 77 women who were positive for T. vaginalis infection at baseline, 58 (75.3%) received treatment by a health care provider. Of those who received treatment, 17 (29.3%) tested positive for T. vaginalis at the 12-month follow-up.

CONCLUSIONS

Given the high prevalence of T. vaginalis among this sample of women, particularly among HIV-positive women, and high levels of reinfection or persistent infection, screening for T. vaginalis among women under community supervision may have a substantial impact on reducing HIV acquisition and transmission among this high-risk population.

Recent Advances in the Trichomonas vaginalis Field

The microaerophilic protist parasite Trichomonas vaginalis is occurring globally and causes infections in the urogenital tract in humans, a condition termed trichomoniasis. In fact, trichomoniasis is the most prevalent non-viral sexually transmitted disease with more than 250 million people infected every year. Although trichomoniasis is not life threatening in itself, it can be debilitating and increases the risk of adverse pregnancy outcomes, HIV infection, and, possibly, neoplasias in the prostate and the cervix. Apart from its role as a pathogen, T. vaginalis is also a fascinating organism with a surprisingly large genome for a parasite, i. e. larger than 160 Mb, and a physiology adapted to its microaerophilic lifestyle. In particular, the hydrogenosome, a mitochondria-derived organelle that produces hydrogen, has attracted much interest in the last few decades and rendered T. vaginalis a model organism for eukaryotic evolution. This review will give a succinct overview of the major advances in the T. vaginalis field in the last few years.

Challenges to the management of curable sexually transmitted infections

Each year, hundreds of millions of new cases of curable sexually transmitted infections (STIs) occur worldwide resulting in reproductive and other serious sequelae, as well as enhanced transmission of HIV. The clinical management and control of these STIs should include as a minimum access to services that provide timely and accurate diagnostic testing together with effective treatment. The provision of appropriate treatment is challenged by the development of increasing antimicrobial resistance, in particular with gonorrhoea and Mycoplasma genitalium infections, requiring new treatments and management algorithms. In addition, infections such as chlamydia, syphilis and trichomoniasis, which show few signs of resistance, are nevertheless highly prevalent and require better public health control measures. While these may be achievable in high income countries, they are still beyond the reach of many low and middle income countries, making substantial improvements in STI management and reductions in STI prevalence challenging.

Clinical and Laboratory Testing for Trichomonas vaginalis Infection

Trichomonas vaginalis infection is highly prevalent in the United States and worldwide. Traditional clinical diagnostic methods fail to identify more than half of these infections that, if left untreated, can result in adverse pregnancy outcomes and an exacerbated risk of both acquisition and transmission of HIV. Women bear a disproportionate amount of the burden of these infections, and testing among populations at risk for this disease should be provided. Molecular technologies have expanded our capacity for laboratory-based detection of infection and can be used on samples already being collected for chlamydia/gonorrhea screening.

Trichomonas vaginalis: a review of epidemiologic, clinical and treatment issues

Trichomonas vaginalis (TV) is likely the most common non-viral sexually transmitted infection (STI) in the world. It is as an important source of reproductive morbidity, a facilitator of HIV transmission and acquisition, and thus it is an important public health problem. Despite its importance in human reproductive health and HIV transmission, it is not a reportable disease and surveillance is not generally done. This is problematic since most persons infected with TV are asymptomatic. Metronidazole (MTZ) has been the treatment of choice for women for decades, and single dose has been considered the first line of therapy. However, high rates of retest positive are found among TV infected persons after single dose MTZ treatment. This has not been explained by drug resistance since in vitro resistance is only 2-5 %. Treatment failure can range from 7-10 % and even higher among HIV+ women. Treatment efficacy may be influenced by vaginal ecology. The origins of repeat positives need further explanation and better treatment options are needed.