Infectious Diseases: Causes & Risks

Bacterial Vaginosis - Topic Overview

Bacterial vaginosis is the most common type of vaginal infection. To learn more about other common types, see the topics Vaginal Yeast Infections and Trichomoniasis.

Post-Polio Syndrome - Topic Overview

Post-polio syndrome is an illness in the nervous system. It can arise 15 to 50 years after you had polio. It affects your muscles and nerves, and it causes you to have low energy, fatigue, and muscle or joint pain. But there

Opportunistic Infections

Giardiasis - Cause

Giardiasis (also called giardia) is caused by infection with the single-celled parasite Giardia lamblia, also known as Giardia intestinalis or Giardia duodenalis.

Giardiasis - What Increases Your Risk

You are at risk for developing giardiasis if:

Tuberculosis (TB) - Cause

Tuberculosis (TB) is caused by Mycobacterium tuberculosis, slow-growing bacteria that thrive in areas of the body that are rich in blood and oxygen, such as the lungs.

Tuberculosis (TB) - What Increases Your Risk

People are at increased risk of infection with tuberculosis (TB) when they:

Pneumonia - Cause

Viruses, bacteria, or (in rare cases) parasites or other organisms cause pneumonia.

Pneumonia - What Increases Your Risk

You are more likely to get pneumonia if you: