1 How you get it: There was an international health scare in May, when an Atlanta man honeymooned in Europe while infected with tuberculosis. This disease is spread when people with TB in their lungs or throat cough, laugh, sneeze, sing or talk, but it's not easy to become infected. Repeated contact is usually necessary in closed spaces over a long period. Transmission in an airplane, although rare, has been documented, according to the American Lung Association.
2 Symptoms: It's possible not to have any symptoms, but a person with TB can have a cough lasting three weeks or longer, fatigue, weight loss, loss of appetite, fever, coughing up blood, night sweats or chest pain. If you think you have been exposed, get a TB skin test.
3 Who's at risk: People with HIV; people in close contact with TB-infected people; diabetics; people who work or live in prisons, nursing homes and other long-term care facilities; health-care workers; people who are malnourished; and alcoholics. Smoking more than 20 cigarettes a day also increases the risk.
4 Latent vs. active: Many people infected with TB bacteria don't develop TB because their immune systems protect them; the bacteria become inactive, but remain alive in the body and can become active later. This is called latent TB, and it's not contagious. Someone with active TB, on the other hand, can spread the disease and must see a doctor right away.
5 It's on the rise: More than one-third of the world's population has TB bacteria, and new infections are occurring at the rate of one per second, says the World Health Organization. Drug-resistant strains have emerged and are spreading, but new vaccines are in development.