Polio vaccine

[Agnes]

The polio vaccine protects against polio, a very contagious viral infection that affects the spinal cord and brain. Polio can cause permanent muscle weakness, paralysis, and sometimes death.
Two formulations are available:

One that contains killed virus and is injected
One that contains live, weakened (attenuated) virus and is taken by mouth

The live-virus vaccine is no longer available in the United States because it can mutate to a strain that causes polio in about 1 of every 2.4 million people who receive the vaccine.
The polio vaccine may be combined with other vaccines, such as the diphtheria, tetanus, and pertussis vaccine and sometimes hepatitis B vaccine or Haemophilus influenzae vaccine.
For more information, see the Centers for Disease Control and Prevention