The BCG vaccine is used to produce immunity against which disease?

The BCG (Bacillus Calmette–Guérin) vaccine is a vaccine primarily used to provide immunity against tuberculosis (TB), a serious infectious disease caused by the bacterium Mycobacterium tuberculosis. Tuberculosis mainly affects the lungs, but it can also target other parts of the body such as the kidneys, spine, and brain. TB spreads through airborne droplets when an infected person coughs or sneezes.

The BCG vaccine is made from a weakened strain of Mycobacterium bovis, which is closely related to the bacteria causing human TB. When administered, the vaccine stimulates the immune system to recognize and fight the tuberculosis bacteria without causing the full-blown disease. This results in immunity, reducing the risk of severe TB, particularly in children.

Other options in the question are incorrect:

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  Whooping cough is prevented by the DPT (Diphtheria, Pertussis, Tetanus) vaccine, not BCG.

  
  


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  Virus fever is a general term and not targeted by BCG.

  
  


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  Smallpox is prevented by the smallpox vaccine, which is a different type of vaccination entirely.

  
  

BCG vaccination is commonly given to newborns and infants in countries where TB is prevalent. Its effectiveness varies but is most protective against severe forms of TB in children, such as meningitis and miliary tuberculosis. While it does not fully prevent TB infection in adults, it is still a critical part of global public health efforts to reduce the incidence and severity of the disease.

Understanding vaccines like BCG is important in Biology and Everyday Science, as it teaches students about immunity, public health, and preventive medicine. The vaccine demonstrates how controlled exposure to weakened pathogens can prepare the immune system to fight real infections effectively.