They may not be sick, but they are carrying TB germs in their lungs across borders, in cars, on ships, on trains and airplanes. TB exacts an enormous personal and financial toll from the world's developing countries. Only one out of every five infected persons has access to effective treatment, which means the disease is constantly being spread. It's estimated that one infectious TB patient is likely to infect 10 to 15 other people with the airborne germ in a one-year period. The World Health Organization has examples in which one infected person spread the disease to hundreds in a single community.
Symptoms start with a cough, then progress through weight loss, fever and coughing up blood.
Ultimately, a patient bleeds to death internally. The typical TB patient in a country such as India or Nepal is 15 to 45 years old. TB kills 2 million people a year. As they endure the disease's progression, patients can't show up for work, and so they lose their jobs. They don't have money for care, and so they often must sell their houses or land, or take out huge loans, to buy medication.