Posted: 3/23/2016
Parkland expert urges awareness to combat highly contagious disease
While some may consider tuberculosis (TB) a disease of the past, public health officials emphasize that tuberculosis is very much still with us and not just in underdeveloped countries.
According to the Centers for Disease Control and Prevention (CDC), there were 9,421 TB cases reported in the United States in 2014, a rate of 2.96 cases per 100,000 people. While the 2014 number of cases and rate declined from the previous year, it was the smallest year-to-year decline in more than a decade. In 2014, the state of Texas reported 1,269 TB cases, or a rate of 4.7 per 100,000 persons, considerably higher than the national rate.
As World TB Day is observed on March 24 this year, health experts remind people to stay informed about the disease.
“It is important to remember that tuberculosis is still out there and be aware of how it is transmitted, as well as how it can be prevented,” said Pranavi Sreeramoju, MD, MPH, Chief of Infection Prevention at Parkland Health & Hospital System and Associate Professor, Medicine-Infectious Diseases at The University of Texas Southwestern Medical Center. “It is a disease that is airborne and contagious. The simple, effective way to prevent transmission is by using cough etiquette or ‘covering one’s cough.’ Early diagnosis and treatment are the best ways to reduce transmission in the community.”
Tuberculosis is caused by bacteria called Mycobacterium tuberculosis. TB bacteria may be expelled from the lungs of an infected person when someone coughs or sneezes. Someone who breathes in those bacteria may develop ‘latent tuberculosis infection.’ People with latent TB infection are not contagious to others. About 10 percent of these individuals go on to develop ‘active TB disease’ in their lifetime if not treated for latent TB.
While TB disease in the lung is contagious to others via aerosol particles, health experts note that infected persons are most likely to spread the disease to those with whom they spend a large amount of time, such as family, friends, coworkers or school mates.
According to the CDC, tuberculosis is not spread by shaking hands with an infected person, sharing food or drink, touching bed linens or toilet seats, sharing toothbrushes or kissing.
“The bacteria usually attack the lungs, but also can attack other parts of the body such as the kidneys, spine and brain,” Dr. Sreeramoju said.
If not treated properly, TB disease can be fatal. It was once the leading cause of death in the United States. In the early 1900s, one of every seven persons living in the U.S. and Europe died as a result of TB. That changed with improved medications and treatment, as well as prevention efforts. But by the 1980s and into the 1990s, cases again started increasing.
To test for latent TB infection, doctors use tuberculin skin test or a blood test. TB disease is diagnosed using multiple means including culturing the bacteria from an infected person’s sputum, imaging of the lungs, PCR test of the sputum and by finding features of TB in tissue specimens.
TB disease can usually be treated through the use of medications. Depending on whether the TB is active or latent, drugs may be administered for 12 weeks to six months, or longer.
“Babies and children, as well as those with compromised immune systems such as people with HIV/AIDS and other chronic conditions are among those most at risk if they come in contact with the TB bacteria,” Dr. Sreeramoju said.
TB disease symptoms can include a bad cough that lasts three weeks or longer, fever, unintentional weight loss and coughing up phlegm with blood from deep inside the lungs.
“While we don’t hear too much about tuberculosis these days because we have one of the lowest rates in the world, there are still almost 10,000 cases reported each year in the U.S.,” Dr. Sreeramoju said. “I think that shows people need to be aware and respond appropriately if there’s any possibility of an infection.”
For more information about tuberculosis, visit www.cdc.gov/tb.