Tuberculosis, often called TB, is an infectious disease that has been with humanity for millennia. Yet, despite advances in medicine, it remains a significant global health challenge. If you’ve ever wondered what TB is, how it spreads, and who is at risk, you’re not alone. Let’s walk through the basics of this complex disease with clarity and compassion.

What Exactly is Tuberculosis?

Tuberculosis is caused by a bacterium called Mycobacterium tuberculosis. It primarily targets the lungs—where oxygen and blood flow are abundant—but it can also travel to other parts of the body, such as the spine, kidneys, or lymph nodes. When it occurs outside the lungs, it’s known as extrapulmonary TB.

One of the most important things to understand about TB is that it exists in two forms: latent and active.

In latent TB, the bacteria live in the body in a dormant state. They aren’t causing symptoms, and the infection isn’t contagious. Your immune system walls them off—but they’re still there. Without treatment, latent TB can eventually become active.

Active TB means the bacteria are multiplying and causing illness. This form of the disease can make you very sick and is contagious if it’s in the lungs.

According to the World Health Organization, about one-third of the world’s population has been infected with TB bacteria. Most have latent TB and may never develop the active disease.

How Does TB Spread?

TB is transmitted through the air. When someone with active pulmonary TB coughs, speaks, or sneezes, they release tiny infectious droplets. If you inhale these droplets, you may become infected.

However, getting infected isn’t the same as getting sick. Many people carry the bacteria without ever developing symptoms or spreading it to others.

What Are the Symptoms?

Latent TB has no symptoms. But active TB usually causes one or more of the following:

• A persistent cough that lasts more than two weeks, sometimes with bloody or thick mucus
• Fever, chills, and night sweats
• Fatigue and weakness
• Loss of appetite and unintentional weight loss
• Shortness of breath or chest pain (in advanced cases)

Because these symptoms develop gradually, it’s easy to mistake them for something less serious—like a cold or the flu. That’s why awareness is critical.

Who Is at Risk?

While anyone can get TB, some people are at higher risk. This includes:

• Those in close contact with a person who has active TB
• Healthcare workers
• People living or working in crowded settings such as prisons, nursing homes, or homeless shelters
• Individuals traveling from or living in regions where TB is common, including parts of Latin America, Africa, Asia, and Eastern Europe
• People with weakened immune systems, including those with HIV, diabetes, or those taking immunosuppressive medications
• Those who are malnourished or underweight

It’s important to remember: stigma and inequality play a role here. Poverty, limited access to healthcare, and social marginalization can increase both exposure and vulnerability.

How Is TB Treated?

The good news is TB is curable. Active TB is treated with a combination of antibiotics taken for several months—usually between 6 to 9 months, sometimes longer.

Sticking to the treatment plan is crucial. Stopping too soon or skipping doses can lead to relapse—and worse, to drug-resistant TB, which is much harder to treat.

Latent TB can also be treated with antibiotics to prevent it from becoming active.

Can TB Be Prevented?

Yes. Prevention strategies include:

• Vaccination: The BCG vaccine is used in many countries, though its effectiveness varies.
• Avoiding close contact with people who have active TB (when possible)
• Ensuring good ventilation in living and working spaces
• Early diagnosis and treatment for those with latent or active TB

A Final Word of Hope

Tuberculosis is a serious disease, but it’s one we understand well. With proper healthcare, education, and global cooperation, we can continue to reduce its impact—and one day, perhaps, eliminate it entirely.

If you or someone you know has symptoms or risks related to TB, please reach out to a healthcare provider. Help is available, and no one should face this illness alone.