Trichomonas vaginalis is a tiny, single-celled parasite that causes a common sexually transmitted infection known as trichomoniasis. It primarily affects the vagina in women and the urethra in men, leading to symptoms like itching, burning, and unusual discharge. Many people may not show symptoms, making it easy to spread without knowing. The infection is typically diagnosed through a simple test and can be effectively treated with antibiotics. Practicing safe sex, such as using condoms, can help prevent the transmission of Trichomonas vaginalis and other sexually transmitted infections. Regular check-ups are important for maintaining sexual health.