10 Causes of Night Sweats

3. Tuberculosis

In centuries past, tuberculosis claimed tens of millions of lives every year until advances in medicine helped reduce occurrences. The disease still claims the lives of around 2,000 people per year in the United States, however. The bacterial infection, which primarily affects the lungs, is more common in people who have a weakened immune system. The first symptom may be a fever accompanied by night sweats. An active case of tuberculosis resembles the flu and pneumonia and is highly contagious.