The Prevnar immunization prevents pneumococcal infections in children, according to Drugs.com. Depending on the age of the child, it is given in a series of one to five shots. Doctors only use the vaccine with children under age 10.
The Prevnar shot does not treat active infections but creates an immunity in the body to such infections, notes Drugs.com. The injection contains proteins from the bacteria to stimulate an immune system response of building antibodies. Pneumococcal infections include pneumonia and meningitis. The pneumococcal bacteria cause infections in the sinuses and inner ear. Pneumococcal infections of the lungs, blood and brain are also possible and are sometimes fatal. While there are risks of side effects with the immunization, the risks are lower than those of infection.