Most Common Curable STI Disproportionately Affects Black Community

The most common curable sexually transmitted disease—trichomoniasis, caused by Trichomonas vaginalis (TV)—disproportionately affects the black community, according to a recent study conducted by investigators from Johns Hopkins School of Medicine.

The Centers for Disease Control and Prevention (CDC) estimate that about 3.7 million individuals living in the United States are infected with trichomoniasis; however, only about 30% of these individuals present with symptoms, and therefore, the majority are not even aware they are infected.

Now, findings yielded from this new study, recently published in the journal Clinical Infectious Diseases, underscore the need to improve racial equity when it comes to addressing TV infections and sexual health overall.

“A higher burden of TV infection in the black population may be due to a combination of factors, [such as] differences in sexual network characteristics (eg, assortative mixing—favoring sexual partners of the same race), differences in individual-level sexual risk behaviors (eg, higher numbers of sexual partners), biological differences in susceptibility to infection, and social and structural disparities (eg, inadequate health care),” senior author of the study Aaron Tobian, MD, PhD, associate professor of pathology at Johns Hopkins, told Contagion^®.

“From a social justice lens, it cannot be underscored that structural racism could be a contributing factor; neighborhood social disorganization has been shown to be significantly associated with TV infection,” he added.

For the study, investigators looked at data collected from a 2013 to 2014 National Health and Nutrition Examination Survey, for which 4057 participants (1942 male / 2115 female) between the ages of 18 and 59 years were enrolled. A total of 822 of the participants identified as non-Hispanic black and 3235 identified as other races/ethnicities.

The participants provided urine specimens which were tested for TV, Chlamydia trachomatis, genital HPV, and herpes simplex virus type 2 serostatus. Because there is a lack of routine surveillance data for TV, identifying the prevalence of TV infection in the participants was the researchers' ultimate goal.

The investigators found that TV infection prevalence was 0.5% and 1.8% among males and females, respectively. TV burden was much higher among black males and females than those who identified as other races/ethnicities at 4.2% and 8.9%, respectively. Furthermore, factors such as being female, more than 40 years of age, having an education level below high school, and living below the poverty level, were all associated with higher TV prevalence, independent of having several sexual partners.

Participants living below the poverty level had a TV prevalence of 3.9% compared with 0.6% for those considered at or above the poverty level. These results are similar to those seen in a previous study which looked at the social context of poverty and its association with TV infection. That study found that TV prevalence was especially high among homeless individuals, as well as adult women who did not have stable living conditions.

Furthermore, in the Johns Hopkins study, TV prevalence was found to be higher in individuals without a high school education (2.9%) compared with those who had at least a high school education (0.8%). A previous study among women living in Southern Brazil, revealed similar results, with those women who had a lower level of education having a higher prevalence of TV.

The good news is that there are actions that clinicians can take to address these racial disparities, such as routine screening and subsequent treatment of men and women living in communities with high TV prevalence.

“If barriers to routine screening exist, clinicians should strongly consider screening high-risk persons in accordance with CDC guidelines," recommended Dr. Tobian. "The high burden of TV infection documented in this population-based study highlights the need to extend screening efforts beyond STD clinics."

Moreover, clinicians need to be cognizant of the need for concurrent presumptive treatment of all sex partners in order to prevent reinfection as well as the need for retesting the index patient after treatment for TV.

“While there may indeed be insufficient empirical evidence that these strategies will lead to epidemic control or a reduction in the racial disparity of TV infection in the United States, it would be an injustice to the black population to continue to ignore this STI until such evidence is available,” Dr. Tobian stressed.

Ultimately, there should be a stronger public health response to TV. According to Dr. Tobian, “A public health response to TV infection in the immediate future is clearly warranted. We are unaware of any national efforts to specifically control TV infection. To increase awareness and public knowledge of TV infection, public health campaigns already in place for HIV/STI prevention could easily begin to include educational information about TV infection.”

Feature Picture Source: CDC / Joe Miller. Feature Caption: This photomicrograph of a wet-mounted vaginal discharge specimen, reveals numbers of Trichomonas vaginalis protozoan parasites, leading to a diagnosis of trichomoniasis, or “trich”, which is a very common sexually transmitted disease that is caused by infection with T. vaginalis. Although symptoms of the disease vary, most women and men who have the parasite cannot tell they are infected.