From the state of Tennessee: The Tennessee Department of Health reminds Tennesseans tuberculosis is a major public health concern. The number of TB cases increased in Tennessee in 2014 to 151 compared to 143 cases reported in 2013.

"As we observe World TB Day, we know we can't let our guard down," said TDH Commissioner John Dreyzehner, MD, MPH. "The Tennessee Department of Health works daily to identify TB infection, prevent TB disease and treat infectious TB disease to help save lives.

"Tuberculosis remains a global epidemic with nearly nine million new cases and more than a million deaths every year," Dreyzehner continued. "Once TB was a leading cause of death in Tennessee, but thanks to prevention and treatment activities TB is now rare here. World TB day marks our hope this disease can eventually be entirely eliminated in our state, across the country and around the world."

Symptoms of active TB in the lungs may include a persistent cough for three or more weeks, chest pain, night sweats, loss of appetite and weight and coughing up blood. TB usually affects the lungs, but can also affect other parts of the body such as the brain, kidneys or spine. If active TB is not treated quickly and appropriately, the disease can be fatal.

TB is caused by a germ called Mycobacterium tuberculosis. It can be spread through the air in microscopic droplets when a person with active TB disease of the lungs coughs or sneezes. A person who shares a closed airspace with someone with active TB disease may inhale some of those germs and could become infected by them.

There is an important distinction between TB infection and TB disease. In TB infection, people are only carrying the germ; they are not sick and can't transmit it to other people. In contrast, when someone has TB disease, he or she is sick and can transmit TB to other people.

"We can detect TB infection with either a TB skin test or a blood test," said Jon Warkentin, MD, MPH, medical director of the Tennessee Tuberculosis Elimination Program. "Persons with TB infection do have a risk of the TB infection developing into TB disease later in life. The good news is we can treat TB infection before it progresses to TB disease, and dramatically reduce risk of TB disease in the future including the risk of spreading it to others."

TDH recommends those at high risk for TB have a skin or blood test to find out if they are infected with TB. Persons at high risk for TB include those born in countries with high rates of TB; individuals infected with HIV or living with AIDS; homeless individuals; people who have spent time in jail or prison; intravenous drug users and those who have had close interactions with someone with infectious TB disease. All Tennessee county health departments offer free TB risk screening and confidential testing and treatment for those at high risk for TB infection.