Tuberculosis is a contagious bacterial disease spread through close, sustained contact with a person whose disease is active and showing symptoms. When the infected person coughs, the disease becomes airborne.

While tuberculosis cases are relatively low in the United States, the disease remains deadly for over 1 million people per year globally.

Tuberculosis can be active or latent in a person’s body. This means either the disease is causing symptoms (active) or is simply existing in the body and lying dormant until circumstances may become suitable for active disease development (latent).

“While we don’t have all the answers as to why some people develop active tuberculosis, and others don’t, we do know that certain people are at higher risk of developing active disease,” says Nebraska Medicine infectious diseases expert Daniel Brailita, MD. “Those at higher risk include very young children, people with a compromised immune system or people who have a severe medical condition.”

Tuberculosis types and symptoms

When people think of tuberculosis, they usually think of the most common type that affects the pulmonary (respiratory) system. However, other less common types exist, as TB may develop into meningitis or affect the spine, lymph nodes, brain, kidneys or urinary system.

Symptoms of active tuberculosis include:

• Persistent, prolonged cough
• Fatigue and weakness
• Fever
• Night sweats
• Coughing up blood (in more progressive disease)

Is there a tuberculosis incubation period?

There is no typical incubation period, as seen with other contagious diseases. How long it takes to develop symptoms depends on whether the disease is active or latent.

“The incubation period for tuberculosis is on a continuum,” adds Dr. Brailita. “A patient with active disease may show symptoms within weeks to a few months, but those with the latent disease may carry it around for years before it transforms into active disease if it does at all.”

Tuberculosis testing

Because tuberculosis symptoms are similar to other respiratory illnesses, a doctor typically won’t test for the disease unless additional circumstances warrant suspicion.

“If a person has respiratory symptoms such as cough for a prolonged period, has been treated for common respiratory illness and is not getting better, has high-risk factors, or has been exposed to a person with active disease, testing would be appropriate,” adds Dr. Brailita. “But unless we have reason to believe the disease is a real possibility, testing isn’t likely needed.”

Testing for exposure involves a simple blood test or an intradermal injection just under the skin's surface. The injection measures immunity and requires two visits to check for a skin reaction. The blood test is used more frequently now, as it only requires one visit and measures the immune response differently than the skin test. Testing for active disease is more complex and involves obtaining samples for microscopy examination, bacterial nucleic acid and cultures.

Tuberculosis treatment

Tuberculosis is caused by a complex, intracellular bacteria that makes it tricky to target with regular antimicrobial drugs. Although treatment can take a while, the disease is curable.

Latent tuberculosis is more straightforward to treat than active tuberculosis. It involves one type of antibiotic medication taken anywhere from four to nine months or a combination of medicines taken for three months. 

Active tuberculosis, especially the pulmonary type, typically requires six to nine months of medication therapy. Less severe cases may require a shorter treatment duration.

Certain tuberculosis cases may be drug-resistant, making treatment more difficult and sometimes requiring over a year or two of therapy.

Is there preventive treatment?

Because very young children are at high risk for developing tuberculosis after exposure, treatment is offered even if the initial test is negative. For others exposed, testing is done to identify those with a latent infection. Once treated, they are no longer able to develop active disease.

Should the recent Omaha tuberculosis scare cause concern?

Thankfully, Nebraska is a low-incidence state when it comes to tuberculosis. “In general, we don’t need to be too concerned with one case of tuberculosis because it is not highly contagious,” says Dr. Brailita. “A person wouldn’t contract it by simply being in the same general vicinity as someone with active disease. Sustained exposure, like you’d have with someone in your household, is more likely to result in a positive diagnosis.”

The exception is children, however, because they are more susceptible to active tuberculosis than healthy adults. This is why the Department of Public Health involved the proper agencies and took appropriate steps to test for everyone’s safety.

Tuberculosis prevention

If you suspect you may have been exposed, talk with your doctor and don’t be afraid to be tested. It’s in your best interest and that of everyone around you.

“Prevention is a public effort, and we are fortunate to have a limited number of tuberculosis cases in Nebraska,” says Dr. Brailita. “When exposure happens, we are here to support one another. We need to resist stigmatizing any contagious disease. With something like tuberculosis, many aren’t even aware they have developed it. It’s curable, and we can prevent further transmission by taking the right steps.”