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6 Common Questions about Tuberculosis, Answered

    6 Common Questions about Tuberculosis, Answered

    Tuberculosis, commonly known as TB, is a bacterial infection that can spread through the lymph nodes and bloodstream to any organ in your body. TB is most often found in the lungs, lungs, as a person gets infected with TB through inhalation of aerosol droplets containing the mycobacteria. How does tuberculosis spread?

    TB spreads from person to person through tiny droplets that are released into the air through coughing or sneezing. Close household contact with an individual with TB is the most important risk factor for the spread of TB.

    The bacteria can also attack any part of the body, including your brain, intestines, and bones, glands, as it gains entry to the blood through your lungs.

    how does tuberculosis spread

    Some who are exposed to TB never develop symptoms because the bacteria can live in an inactive form in the body, also known as the latent infection. But if the immune system weakens, as is often the case in people in people with immunosuppressive conditions such as HIV infection and AIDS, end stage kidney disease, diabetes mellitus, and cigarette smoking.

    TB bacteria can become active again (the condition is called reactivation TB).

    In their re-activated state, TB bacteria cause death of tissue in the organs they infect. Reactivation TB disease can be fatal if left untreated.

    Whether you’re living with this condition or you want to lessen your risk, information is key.

    Here’s some of the most pressing questions about tuberculosis, answered.

    What are the Symptoms of Tuberculosis?

    Aside from answering “how does tuberculosis spread?,” it also helps to know how to spot its signs.

    TB usually develops slowly. In majority of cases, after primary TB infection (i.e. entry of TB into your lungs), 90 percent of individuals with intact immunity control the spread of the bacteria and enter a latent phase.

    The infection doesn’t cause any symptoms, and this is known as Latent TB. The person remains asymptomatic, but this latent disease can potentially become active at any time. An estimated 2 billion people have latent TB and anywhere from 5 to 15 percent of these people will suffer from reactivation of TB during their lifetime.

    When you display symptoms, it’s called Active TB.

    Latent TB:

    With this condition, you have a TB infection, but the bacteria remains in your body in an inactive state. It causes no symptoms. Latent TB, which is also called inactive TB or TB infection, isn’t contagious. Even then, it can turn into active TB, so treatment is important to help control the spread of TB.

    Active TB

    This condition makes you sick and can spread to others. It can occur in the first few weeks after infection with the TB bacteria, or it might occur years later.

    Signs and symptoms of active TB include:

      • Coughing that lasts three or more weeks
      • Coughing up blood
      • Chest pain, or pain with breathing or coughing
      • Unexplained weight loss
      • Fatigue
      • Fever -mostly no fever in the morning, but temperature rises towards the evening, resulting in night sweats
      • Loss of appetite

    Tuberculosis usually affects your lungs, but it can also affect other parts of your body, such as your spine, your kidneys or your brain.

    What Should I Do If Someone I Know Has TB?

    If you think you have been exposed to someone with TB disease, you are recommended to contact your doctor or local health department to carry out a TB skin test or a special TB blood test. Don’t forget to let your doctor know when you were in contact with the person who has the TB disease.

    Also, visitors should wear N95 masks while visiting patients with known or suspected active TB

    When Should I Seek Medical Care?

    You should contact your doctor if you have a fever, unexplained weight loss, drenching night sweats or a persistent cough. These are often signs of TB, but they may also be symptoms of other medical problems. Your doctor can perform tests to help determine the cause.

    How Do I Prevent TB?

    Aside from knowing how does tuberculosis spread, it also helps to know what you do if you do get infected.

    To prevent TB, you should:


    In countries where tuberculosis is more common, infants often are vaccinated with bacillus Calmette-Guerin (BCG) vaccine because it can prevent severe tuberculosis in children. However, the BCG vaccine isn’t recommended for general use because it isn’t very effective in adults. Dozens of new TB vaccines are in various stages of development and testing.

    Avoid exposure to anyone with active TB

    Do NOT spend long periods of time with anyone who has active TB until that person has been treated for at least two weeks.

    Use protective equipment

    If you must come in contact with someone who has active TB, it would be best to use protective equipment such as N95 face masks and gloves. If you work in a facility that cares for people who have untreated TB, personal protective equipment is a must..

    Facilitate treatment

    If you live with someone who has active TB, help and encourage that person to follow treatment instructions.

    How Do I Prevent Others From Getting Tuberculosis?

    If you have active TB, you need to isolate yourself, take your medications, and ensure that others do not get infected. It generally takes a few weeks of treatment with TB medications before you’re not contagious anymore. Follow these tips to help keep your friends and family from getting sick:

    Follow your entire course of medication

    This is the most important step. If you stop treatment early or skip doses, TB bacteria have a chance to develop mutations that allow them to survive the most potent TB drugs. The resulting drug-resistant strains are much more deadly and difficult to treat.

    Stay home

    Don’t go to work or school until you are free from TB, or at least completed several weeks of treatment. Do not sleep in a room with other people during the first few weeks of treatment for active tuberculosis.

    Ventilate the room

    How does tuberculosis spread?

    Tuberculosis germs spread more easily in small, closed spaces where air doesn’t move. If it’s not too cold outdoors, open the windows and use a fan to blow indoor air outside.

    Cover your mouth and nose when coughing or sneezing

    Use a tissue to cover your mouth anytime you laugh, sneeze or cough. Put the dirty tissue in a bag, seal it and throw it away.

    Wear a mask

    Wearing a surgical mask when you’re around other people during the first three weeks of treatment may help lessen the risk of transmission.


    Learn more about tuberculosis, here.

    Hello Health Group does not provide medical advice, diagnosis or treatment.

    Understanding Tuberculosis – the Basics. http://www.webmd.com/lung/understanding-tuberculosis-basics. Accessed August 20, 2016. Tuberculosis - Symptoms and Causes http://www.mayoclinic.org/diseases-conditions/tuberculosis/symptoms-causes/dxc-20188557. Accessed August 20, 2016. Understanding Tuberculosis – Diagnosis and Treatment. http://www.webmd.com/lung/understanding-tuberculosis-treatment. Accessed August 20, 2016.
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    Written by Vincent Sales Updated Aug 29, 2020
    Medically reviewed by Mike Kenneth Go Doratan, MD
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