TRICHOMONIASIS – A DISEASE OVERVIEW
Trichomoniasis is the most common, non-viral sexually transmitted disease (STD) in the world [1, 2]. Infection is caused by the protozoan Trichomonas vaginalis (“Trichomonas”) and overt symptoms are recognized in approximately 50% of infected women. US incidence is estimated at 5 to 8 million cases per year [3-5], and with worldwide incidence estimates ranging from 170 to 350 million cases per year (see Figure 1) [6-8]. Precise estimates are hampered by the poor efficacy of diagnosis [9], the variability in symptomology, and the poor reporting rates for Trichomonas infection, which is among the lowest for all STDs. Accordingly, Trichomonas infection rates in the US and elsewhere may be considerably higher than previously thought.

Current Methods For Diagnosing Trichomonas Infection Are Inadequate
Trichomonas infection in women leads to vaginitis and may contribute to 30% of all vaginitis cases (10 to 20 million/year US). However, it is commonly mistaken for either a yeast or bacterial infection, the two other main causes of vaginitis [10]. Part of the problem in diagnosing Trichomonas infection is that the symptomology varies widely: up to 50% of women may be misdiagnosed. Trichomonas infection, unlike many STDs cannot be consistently inferred from the clinical presentation. Although some manifestations of the disease, such as “strawberry cervix,” have a very high correlation with infection. Most patients do not have this symptom. Indeed, none of the commonly associated symptoms of Trichomonas infection (i.e. yellow, frothy, or purulent vaginal discharge, puritus, odor, pelvic inflammation, abdominal pain, and strawberry cervix) can be relied upon to define Trichomonas infection. Therefore, diagnosis must be made upon the detection of live, motile organisms through direct microscopic examination of a vaginal sample or by culturing the organism [11]. Wet mount microscopy is the most common method of diagnosis, but requires trained observers and access to a microscope. Even in expert hands this technique is found to be only 58% sensitive [12]. The other major diagnostic method, detection of the organism in culture, is considered more accurate than microscopy. However, it takes 2 to 5 days to obtain culture results, and culture also requires specialized laboratory equipment. Moreover, culture is still only 68% sensitive [12] and cannot be performed from urine samples [13]. Culture also has the major drawback of delaying the time to treatment by several days. During this interval the infection can be spread to others and the patient continues to suffer.

Inadequate Diagnosis Contributes To The Low Rates Of Treatment And A Sustained Disease Burden
Failure to return for therapy when the patient must wait for test results is a major problem with all STD diagnoses. The lack of accurate point of care diagnosis for Trichomonas infection results in a situation where up to 50% of the women are misdiagnosed and subsequently mistreated. This leads to additional doctor visits, high rates of patient “dropout,” and low rates of successful treatment. This imposes a tremendous economic burden on society. Without treatment, infection in women is non-self-limiting. Infection has serious health consequences. Men, who typically suffer from a shorter duration of infection than women (approximately two weeks to four months), are almost never diagnosed yet can easily transmit the parasite to women [14,15].

Trichomonas Infection Can Be Easily And Effectively Treated At Low Cost – If Accurately Diagnosed
Unlike other causes of vaginitis, Trichomonas is an STD, and so both partners should be treated for infection. Currently, Flagyl (metronizadole) is the only treatment available in the US and is effective after treatment [16-17]. However, given the potentially serious side effects of this drug, treatment for suspected Trichomoniasis is not necessarily recommended. Better diagnostic accuracy would help to prevent the unnecessary use of Flagyl, an important factor considering that increasing numbers of Flagyl-resistant Trichomonas infections are being reported.

Failure To Treat Trichomonas Infection Can Have Serious Health Consequences For Women and Men
As is the case for other chronic sexually transmitted infections (i.e. Chlamydia), an increasing amount of evidence suggests that Trichomonas infection can have many secondary adverse health consequences. A particularly serious aspect of Trichomonas infection in women is an increased susceptibility to HIV infection [18]. The correlation between Trichomoniasis and increased risk of acquiring HIV has now been established. Trichomonas vaginalis is one of the most important cofactors in amplifying HIV transmission. The pathology induced by T. vaginalis during co-infection with HIV can increase HIV shedding [35]. Trichomonas infection appears to also act to expand the portal of entry for HIV in an HIV-negative person. Importantly, symptomatic men with Trichomoniasis increase HIV viral load in semen [36]. Without a doubt, accurate diagnosis and treatment of Trichomoniasis reduces the potential for HIV infection among susceptible individuals [21, 22].

In addition, Trichomonas infection - a chronic disease that can persist indefinitely in women - is associated with an increased risk of cervical cancer [23-30]. Cervical cancer is a leading cause of death in women worldwide, and is known to result from infection by Human Papilloma Virus (HPV). The relationship of Trichomonas infection (which unlike HPV is treatable) to cervical cancer is an area of intense clinical interest worldwide.

Furthermore, Trichomonas infection is also being increasingly recognized for its impact on reproduction success and pregnancy outcomes. It is estimated that 25% of pregnant women in some populations are infected with Trichomonas, in part due to the overlapping demographics of infection risk and reproductive age, both of which tend to be concentrated in the 18-30 year age group. Trichomonas infection is associated with an increased risk of adverse events occurring both during and after the pregnancy and therefore, an increased demand for pre- and postnatal care [6, 31]. Moreover, infection with Trichomonas can reduce the chances of conception, a factor not often considered for the millions of women seeking fertility treatment [32-34].