Neuroinflammation and Infection: Molecular Mechanisms Associated with Dysfunction of Neurovascular Unit

What Is Tuberculosis And How Does It Spread?

Shot of a senior woman suffering from chest pain while sitting on the sofa at home.

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Although it's often thought of as a disease of the past, tuberculosis is still found widely around the world, killing around 1.25 million people annually.

The U.S. Typically sees thousands of tuberculosis disease cases every year. Right now, Kansas is in the midst of a major outbreak that's infected hundreds of people and sadly killed two.

So, what causes tuberculosis and how can you prevent its spread?

What Is Tuberculosis?

Tuberculosis is usually caused by infection with a bacterium called Mycobacterium tuberculosis. It primarily affects the lungs, but can also harm the kidneys, the brain and the spine, according to the Centers for Disease Control and Prevention.

The condition comes in two forms: latent and active. In latent TB cases, the germs linger in the body but don't cause symptoms or spread to others. In active cases, people develop symptoms and can pass on the disease.

Without treatment, a latent tuberculosis infection may still become active, should a person's immune system fail to keep levels of the bacteria low. This happens to about 10% of people with latent TB in the U.S.

In total, the CDC estimates about 13 million people have latent TB nationwide. Treating inactive tuberculosis is important to prevent the risk of developing symptoms and reduce the chance of transmitting the disease to others.

What Are The Symptoms Of Tuberculosis?

Active tuberculosis causes symptoms including a long-lasting cough, weakness, fatigue, chest pain, coughing up blood, fever, chills, night sweats and a lack of appetite. People with the disease may also find they lose weight.

If it affects other parts of the body than the lungs, other symptoms may appear, according to the CDC. Tuberculosis can lead to red or purple swelling under the skin if the lymph nodes are infected, headache or confusion should the brain be infected, or blood in the uring of people with infected kidneys.

Tuberculosis may also lead to vocal hoarseness if it infects the larynx, or back pain if it affect the spine.

How Is Tuberculosis Treated?

Doctors usually give people with tuberculosis medicine for several months, whether it's active or latent. Many people will take a combination of medications, including antibiotics, for between three and nine months. They may experience side effects like skin rashes and an upset stomach. Occasionally the drugs can cause more serious side effects, like liver damage.

Some tuberculosis cases are drug-resistant, which can make them harder to treat. Patients with drug-resistant TB may take stronger medicines in an effort to kill the disease. This kind of drug regime can be complicated and cause different side effects. Patients with drug-resistant TB may take medication for years.

Although there is a vaccine against tuberculosis, it isn't usually given in the U.S., where rates of the disease are relatively low.

How Does Tuberculosis Spread?

Tuberculosis spreads through germs released when a person with TB in their lungs coughs, speaks or sings. These bacteria can stay in the air for prolonged periods of time and are more likely to spread to other people indoors and in poorly-ventilated spaces.

People who breathe in these germs may become infected, with those who spend more time in close proximity to someone with TB at greater risk. For this reason, the disease often spreads between people who live together, like family members, or who see each other every day at work or social activities.

Only people with active TB can pass on the disease.

Tuberculosis bacteria are not spread through other common infection pathways, like shaking hands, kissing or touching bed sheets.

Who Is Vulnerable to Tuberculosis?

Some people are more likely to develop active disease if they catch tuberculosis. This includes those with health conditions that weaken the immune system, such as HIV infection, diabetes and severe kidney disease.

Some people are more likely to catch tuberculosis in the first place, including those who often travel to countries where the disease is more common, and those who live or work in places such as healthcare facilities, prisons or homeless shelters.

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