Final answer:
The three most common causes of infectious vaginitis are Candida, Trichomonas, and Bacterial vaginosis, usually caused by Gardnerella vaginalis and characterized by symptoms like discharge and itching.
Step-by-step explanation:
The three most common causes of infectious vaginitis are Candida, Trichomonas, and Bacterial vaginosis. Vaginitis is often a result of infections by microorganisms such as the yeast Candida albicans, which causes vaginal candidiasis, or by single-celled parasites like Trichomonas vaginalis, which is typically transmitted through vaginal intercourse. Bacterial infections of the vagina, known as bacterial vaginosis, are usually caused by Gardnerella vaginalis, coupled with a decrease in lactobacilli and an increase in vaginal pH.
These conditions can lead to symptoms such as discharge, odor, itching, and burning. It is important to accurately diagnose the cause of vaginitis to provide effective treatment, which may include oral or topical antimicrobial agents. Factors such as wearing tight clothing, using certain hygiene products, and changes in the microbiota can increase the risk of developing these infections.