Prevalence of Trichomonas vaginalis in a male sexually transmitted disease clinic population by interview, wet mount microscopy, and the InPouch TV test

TRICHOMONAS VAGINALIS INFECTION AMONG ASYMPTOMATIC UNDERGRADUATE STUDENTS IN A PRIVATE UNIVERSITY IN OGUN STATE, NIGERIA

Background

Trichomonas vaginalis is one of the common non- viral sexually transmitted infections that infect both men and women worldwide. It is largely asymptomatic and its association with the risk of HIV transmission has made it a compelling public health concern. Therefore, this study aims to determine the prevalence and the risk factors associated with T. vaginalis among asymptomatic undergraduate students at Babcock University, Ilisan-Remo, Ogun state, Nigeria.

Materials and Methods

This is a descriptive cross-sectional study involving 246 asymptomatic students of Babcock University between February 2019 to April 2020. Information on socio-demographic and associated risk factors was obtained by structured-questionnaire in an interview-based manner. First-void urine was collected from each participant for the detection of T. vaginalis using the traditional wet prep method and TV in-pouch. The data were analyzed by SPSS Version 23.

Results

The overall prevalence of T. vaginalis among the participants was 12.2% (30/246). The use of wet-preparation showed 8.5% (21/246) while the use of TV inpouch yielded 12. 2% (30/246) prevalence of positive results. The results of the wet prep in comparison to the in-pouch technique was statistically significant among the study population. (P < 0.001). Sexual intercourse, use of hormonal contraceptives and practice of internet-based sex seeking behaviour were factors that had increase likelihood of T. vaginalis infection on multivariate analysis.

Conclusion

The occurrence of T. vaginalis and, its associated risk factors among the asymptomatic population in this study is very high. We advocate for the screening of young people.

Trichomonas vaginalis contact-dependent cytolysis of epithelial cells

Trichomonas vaginalis is an extracellular protozoan parasite that binds to the epithelium of the human urogenital tract during infection. In this study, we examined the propensities of 26 T. vaginalis strains to bind to and lyse prostate (BPH-1) and ectocervical (Ect1) epithelium and to lyse red blood cells (RBCs). We found that only three of the strains had a statistically significant preference for either BPH-1 (MSA1103) or Ect1 (LA1 and MSA1123). Overall, we observed that levels of adherence are highly variable among strains, with a 12-fold range of adherence on Ect1 cells and a 45-fold range on BPH-1 cells. Cytolysis levels displayed even greater variability, from no detectable cytolysis to 80% or 90% cytolysis of Ect1 and BPH-1, respectively. Levels of adherence and cytolysis correlate for weakly adherent/cytolytic strains, and a threshold of attachment was found to be necessary to trigger cytolysis; however, this threshold can be reached without inducing cytolysis. Furthermore, cytolysis was completely blocked when we prevented attachment of the parasites to host cells while allowing soluble factors complete access. We demonstrate that hemolysis was a rare trait, with only 4 of the 26 strains capable of lysing >20% RBCs with a 1:30 parasite/RBC ratio. Hemolysis also did not correlate with adherence to or cytolysis of either male (BPH-1)- or female (Ect1)-derived epithelial cell lines. Our results reveal that despite a broad range of pathogenic properties among different T. vaginalis strains, all strains show strict contact-dependent cytolysis.

Trichomonas vaginalis screening and prevention in order to impact the HIV pandemic: Isn't it time we take this infection seriously?

Trichomonas vaginalis (TV) is the second most common sexually transmitted infection (STI) in the world. It is associated with significant morbidity in women: pelvic inflammatory disease (PID), concurrent vaginitis and sexually transmitted infections (STIs), post-operative infection, and pregnancy complications. TV infection has been implicated in HIV acquisition and transmission in men and women. There are multiple mechanisms to explain this association. TV is not routinely screened for in asymptomatic patients; however, infected individuals are most often asymptomatic. Due to the association with the spread of HIV infection, screening should not be limited to symptomatic patients or those seeking treatment for STIs. There are a variety of tests available to detect TV. Treatment of TV has demonstrated lower rates of HIV acquisition in at risk women. In HIV positive men and women, treatment decreases the amount of genital HIV shedding and subsequent infectivity. Initiation of an effective TV screening and treatment program in HIV positive and HIV susceptible populations may limit further transmission of HIV.

Current issues and considerations regarding trichomoniasis and human immunodeficiency virus in African-Americans

Trichomonas vaginalis has long been recognized as one of the most prevalent sexually transmitted infections. However, it is only in recent years that it has been appreciated that Trichomonas may play a critical role in amplifying human immunodeficiency virus (HIV) transmission. Given the evidence that T. vaginalis likely promotes HIV infection, the apparent high level of Trichomonas infection in the African-American community is cause for concern. Even if T. vaginalis increases the risk of HIV transmission by a small or modest amount, it translates into a sizable population effect since Trichomonas is so common in this community. Therefore, control of trichomoniasis may represent an important avenue of control for the prevention of HIV transmission, particularly among African-Americans.

Timing of inoculation of the pouch makes no difference in increased detection of Trichomonas vaginalis by the InPouch TV method

The InPouch TV is a method which combines a wet preparation and a culture method to detect Trichomonas vaginalis. The top portion of the InPouch TV essentially functions as a slide to be examined under the microscope. If the initial examination is negative, the specimen is pushed down into the bottom pouch, which serves as a broth for cultivation. The issue of timing has not been specifically addressed for optimal processing. To assess the effect of timing on the inoculation of the bottom pouch, we conducted a study designed to determine which procedure had better sensitivity, that of delaying inoculation of the bottom pouch until the initial examination on the top pouch is performed (method A) or that of immediately inoculating the bottom pouch (method B). In addition, we compared the sensitivity of the InPouch TV to that of the traditional wet mount. Fifty of 498 specimens were positive. Methods A and B had identical results: 31 specimens were initially positive regardless of transit time, and incubation yielded another 19 positives. The wet preparation detected 36 positive specimens. The sensitivities of the methods were 100% for the InPouch TV (including examination on receipt and after incubation) and 72% for the traditional wet mount. In conclusion, the InPouch TV method is more sensitive than the traditional method and no detectable differences were observed with timing of the inoculation of the top or bottom pouch.

Trichomonas vaginalis, HIV, and African-Americans

Trichomonas vaginalis may be emerging as one of the most important cofactors in amplifying HIV transmission, particularly in African-American communities of the United States. In a person co-infected with HIV, the pathology induced by T. vaginalis infection can increase HIV shedding. Trichomonas infection may also act to expand the portal of entry for HIV in an HIV-negative person. Studies from Africa have suggested that T. vaginalis infection may increase the rate of HIV transmission by approximately twofold. Available data indicate that T. vaginalis is highly prevalent among African-Americans in major urban centers of the United States and is often the most common sexually transmitted infection in black women. Even if T. vaginalis increases the risk of HIV transmission by a small amount, this could translate into an important amplifying effect since Trichomonas is so common. Substantial HIV transmission may be attributable to T. vaginalis in African-American communities of the United States.

High prevalence of trichomoniasis in rural men in Mwanza, Tanzania: results from a population based study

OBJECTIVES

To measure the prevalence of urethral infections including trichomoniasis in rural Tanzanian men, to assess the prevalence of symptoms and signs among men with Trichomonas vaginalis, and to analyse the risk factors for trichomoniasis.

DESIGN

A cross sectional study of 1004 men aged 15-54 years in a rural community in north west Tanzania.

METHODS

Participants were interviewed about sexual behaviour and symptoms of sexually transmitted diseases. First fraction urine samples and urethral swabs were collected and used to test for T vaginalis by wet preparation and culture, Neisseria gonorrhoeae by culture, Chlamydia trachomatis by ligase chain reaction and non-specific urethritis by Gram stain. Urine was also tested for the presence of leucocytes using a leucocyte esterase dipstick. Men were re-interviewed 2 weeks later to document new symptoms and signs of urethritis.

RESULTS

Complete laboratory results were available on 980 men. One in four men had laboratory evidence of urethritis. T vaginalis was found in 109 individuals (11%), gonorrhoea in eight (0.8%), and chlamydial infection in 15 (1.5%). Over 50% of men with urethritis were asymptomatic. The prevalence of signs and symptoms was similar among men with T vaginalis alone compared with men with other urethral infections. The sensitivity and specificity of the leucocyte esterase dipstick (LED) test for detecting T vaginalis were 80% and 48% respectively in symptomatic men and 60% and 68% in asymptomatic men. Factors associated with trichomoniasis included religion, type of employment, and marital status.

CONCLUSIONS

A high prevalence of urethritis was found in men in this community based study. More than half of the urethral infections detected were asymptomatic. The most prevalent pathogen was T vaginalis. Studies are needed on the prevalence of trichomoniasis in men presenting to health services with complaints suggestive of urethritis since treatment for T vaginalis is not included in the syndromic management of urethritis in most countries. The performance of the LED test as a screening test for trichomoniasis was unsatisfactory in both symptomatic and asymptomatic men. Improved screening tests are urgently needed to identify urethral infections that are asymptomatic and which are not covered by current syndromic management algorithms.

Trichomonas vaginalis epidemiology: parameterising and analysing a model of treatment interventions

BACKGROUND

Trichomonas vaginalis, which affects at least 170 million individuals globally, may increase the risk of transmission of HIV and predispose pregnant women to premature rupture of membranes and early labour.

OBJECTIVE

To more clearly define the epidemiology of trichomoniasis and to develop a mathematical model of disease transmission dynamics in order to explore various treatment strategies.

DESIGN

A deterministic model of trichomoniasis was constructed. Parameter values were set to fit the model to known endemic prevalence levels of Trichomonas vaginalis. Two treatment interventions ("screening" and "syndromic management") were simulated.

RESULTS

The age specific prevalence of the disease was seen to differ from other STDs in a number of studies. Parameter fitting indicates that the average duration of infection in women is at least 3-5 years and approximately 4 months for men. "Syndromic management" (that is, treating only those with symptoms of disease) had minimal effect upon the endemic prevalence of disease even at high levels of coverage. "Screening" (that is, identification of individuals with both symptomatic and asymptomatic infection) was shown to be the most efficient method of control, but was sensitive to the screening interval.

CONCLUSIONS

The control of trichomoniasis seems to have been a success in developed countries because of the regular access to health care, whereas it has remained endemic in many developing countries where control may only be possible by regular screening and treatment. However, without a large investment in services, success in controlling trichomoniasis is likely to be transitory.