A large study indicates that the sexually transmitted parasite Trichomonas vaginalis (TV) is harbored by many women in their 40s, with the highest infection rate found in women aged 45 years and older.

Charlotte Gaydos, MS, DrPH, and fellow researchers collected samples from 7,593 U.S. women aged 18 to 89 years undergoing routine screening for Chlamydia trachomatis (CT) and Neisseria gonorrhea (NG) in a variety of clinical settings in 21 states. The specimens were retrospectively tested for TV. Findings were first reported at the annual meeting of the International Society for STD research.

Overall prevalence rates of TV, CT and NG were 8.7%, 6.7% and 1.7%, respectively. TV prevalence ranged from 7.5% to 8.6% in women aged 18 to 39 years and increased to 9.8% in those aged 40 to 44 years. The highest prevalence was seen among women aged 45 to 49 years (13.4%) and those over age 50 years (13%).

In contrast, CT and NG prevalence rates were less than 2% in women aged 40 and older and highest in women under age 30 years, ranging from 5.2% to 14.3% for CT and 1.3% to 3% for NG.

T. vaginalis infections are quite treatable with antibiotics, and these high numbers really warrant older women getting screened by their family [clinicians] and gynecologists during routine checkups to make sure they are not infected and are not inadvertently spreading it to others,” Gaydos advised in a statement. “What we are really witnessing with T. vaginalis — especially in older women — is that no one ever looked, no one ever tested and diagnosed, and no one is really getting treated, so the infection persists year after year.”