Tuberculosis (TB) is an infectious condition that can be fatal without treatment. It occurs following infection with the bacterium species Mycobacterium tuberculosis. The Bacille Calmette-Guérin (BCG) vaccine can help protect people from developing TB. However, in certain countries, such as the United States, health experts do not generally recommend using the vaccine.
TB is a condition that typically affects the lungs but can damage other organs. While it is
Although most TB cases occur in
In this article, we discuss the safety and efficacy of the BCG vaccine and who should consider getting it.
However, not every person with a TB infection will become ill. There are
In cases of latent TB, a person’s immune system can fight the bacteria and prevent progression to TB disease. In contrast, an individual with a latent TB infection will experience no symptoms and cannot spread the infection to others.
However, in other cases, the immune system cannot prevent the bacteria from multiplying. When the TB bacterium is active, experts refer to this as TB disease. In these cases, the bacterium causes people to experience symptoms such as fever, pain in the chest, and coughing up blood or sputum. People with TB disease can transmit TB to others.
The BCG vaccine uses an
Evidence suggests that the BCG vaccine is safe. However, as with any vaccine, it is possible for people to experience side effects or adverse reactions. These may include:
- soreness at the injection site
- a small scar at the injection site
- swollen glands
While rare, more serious complications can include allergic reactions, abscesses, bone inflammation, and widespread TB.
As the BCG vaccine is a live-attenuated vaccine,
Research suggests that the BCG vaccine is 70–80% effective against the most severe forms of TB, such as TB meningitis. However, it is less effective against the form of TB that affects the lungs.
This finding is consistent with other evidence suggesting that the vaccine has an efficacy ranging of
There is limited data investigating the duration of protection from BCG vaccination, with some research suggesting protection lasts for
However, in some cases, a healthcare professional may consider a BCG vaccine following a consultation with a TB expert and if people meet specific criteria. They may also discuss the situation with the
According to the
If a child is negative for a TB skin or blood test and is in frequent contact with an adult with TB disease, they may be suitable for the vaccine. Similarly, if healthcare professionals are in an environment where they interact with individuals with TB disease, they may also consider the vaccine.
Health experts in the U.S.
Aside from the BCG vaccine, people can implement other TB prevention strategies. These can help stop TB infection from progressing to TB disease and may also protect others in the community. Typically, this
Precautions people can take to limit the spread of TB may include:
- completing their course of medications and taking the drugs exactly as their doctor prescribes
- covering the mouth and nose when coughing and hand washing properly
- using an effective mask or face covering, such as an N95 mask
The BCG vaccine is a preventative measure to help limit the spread of TB. It uses a weakened strain of the M.Tuberculosis bacterium to stimulate the immune system and help prevent future infections.
In the U.S., health experts do not generally recommend administering the vaccine. This is due to a low risk of infection, variable effectiveness, and possible interference with diagnostic tests. However, the vaccine may be suitable for people in high-risk groups, such as children and healthcare workers.