Development of a nonhuman primate model for Trichomonas vaginalis infection.

OBJECTIVE

Trichomoniasis, caused by Trichomonas vaginalis, is a prevalent sexually transmitted infection associated with increased risk of HIV infection. An animal model of T. vaginalis infection would enable scientists to further investigate trichomoniasis.

STUDY

DESIGN

Seven macaques (4 test vs. 3 control) were enrolled in a 2-week pilot study. Eight additional animals participated in a 2-arm (T. vaginalis vs. sham inoculated) crossover study lasting 5 weeks before treatment. In all, 12 Macaca nemestrina monkeys were challenged with a single intravaginal inoculation of 6.6 to 7.1 x 10(5) trichomonads (ATCC 50148). Vaginal culture (InPouch TV), colposcopy, microbiology, pH, and cervical cytokines were assessed at baseline, day 2, and weekly thereafter.

RESULTS

Ten of 12 challenged animals tested positive for trichomoniasis for 2 weeks or longer. One animal tested positive on days 2 and 7 but negative thereafter. Only one animal was not infected. Oral metronidazole treatment (35 mg/kg per day for 3 days) resolved infection in all animals. Trichomoniasis infection did not lead to shifts in vaginal microbiology or pH.

CONCLUSIONS

A single T. vaginalis inoculation results in persistent infection in the pigtailed macaque.