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What is Pneumococcal Disease?

Older adult and toddler

Pneumococcal disease is an infection caused by a type of bacteria called Streptococcus pneumoniae. When these bacteria invade the lungs, they can cause pneumonia. They can also invade the bloodstream, causing bacteremia, and/or invade the tissues and fluids surrounding the brain and spinal cord, causing meningitis. Pneumococcal disease can also cause middle ear infection and sinus infections.

Pneumococcal disease is a very serious illness. Invasive pneumococcal disease kills thousands of people in the US each year, most of them age 65 years or older. It is also the most common cause of invasive bacterial infection in US children. Pneumococcal disease in young children can lead to meningitis, bacteremia, otitis media (ear infections) and, in some cases, death. Children under 2 years of age fall into the highest general risk group for invasive pneumococcal infections.


The best way to protect against pneumococcal disease is through vaccination. There are two types of pneumococcal vaccines currently available: a conjugate vaccine recommended for all children younger than 2 years and a polysaccharide vaccine recommended for all adults age 65 and older and all individuals older than 2 years with certain underlying medical conditions.

A single dose of the pneumococcal polysaccharide vaccine protects against the 23 types of Streptococcus pneumoniae bacteria that are responsible for causing more than 90 percent of all pneumococcal disease cases in adults.

The pneumococcal conjugate vaccine, administered to infants and toddlers before their second birthday, protects against the 86 percent of the bacteria types that cause blood infections in children and 83 percent of those that cause meningitis in children.


The symptoms of pneumococcal disease vary depending on the illness caused by the bacteria.

In adults, symptoms of pneumonia include sudden onset of illness characterized by shaking chills, fever, shortness of breath or rapid breathing, chest pain that is worsened by breathing deeply and a productive cough. The symptoms of pneumococcal meningitis include stiff neck, fever, mental confusion and disorientation, and photophobia (visual sensitivity to light). The symptoms of bloodstream infection may be similar to some of the symptoms of pneumonia and meningitis, along with joint pain, fever and chills.

In infants and young children, signs and symptoms of pneumonia may not be specific and may include fever, cough, rapid breathing or grunting. The symptoms of meningitis may vary depending on the age of the child, but may include diarrhea, vomiting and/or fever. In older children, meningitis symptoms may include headache, sensitivity to light and/or a stiff neck. Bloodstream infections typically have non-specific symptoms including fever and irritability. Children with otitis media typically have a painful ear. Other symptoms that may accompany otitis media include sleeplessness, fever and irritability.

Who should get pneumococcal disease vaccine?

Vaccination against pneumococcal disease is recommended for:

  • Adults age 65 and older
  • Infants and toddlers younger than 2 years old
  • Children, adolescents, and adults age 2-64 years with certain medical conditions

Vaccine Safety

The pneumococcal vaccines are safe and effective in preventing illness and death due to pneumococcal disease. Some adults have experienced mild side effects, but these are usually minor and last only a short time. When side effects do occur, the most common include swelling and soreness at the injection site. A few adults experience fever and muscle pain. In children, the conjugate vaccine may cause mild fever, fussiness, and decreased appetite.

As with any medicine, there are very small risks that serious problems could occur after getting the vaccine. However, the potential benefits associated with pneumococcal disease are much greater than potential risks associated with the pneumococcal vaccine.

Key Facts about Pneumococcal Disease and its Prevention

  • Pneumococcal disease is an infection caused by bacteria called Streptococcus pneumoniae. These bacteria can invade the lungs, bloodstream, and the tissues and fluids surrounding the brain and spinal cord, resulting in a number of different illnesses, including pneumonia and meningitis.
  • It is estimated that about one million US adults get pneumococcal pneumonia each year, as many as 400,000 hospitalizations from pneumococcal pneumonia occur annually in the US, and about 5-7% of those who are hospitalized from it will die. The death rate is even higher in those age 65 years and older. Fewer people will get pneumococcal meningitis or bloodstream infection, but the mortality rate for these infections is even higher.
  • Pneumococcal disease can be prevented among adults and children with two safe and effective vaccines: a conjugate vaccine and a polysaccharide vaccine.
  • You cannot get pneumococcal disease from the vaccine.
  • Pneumococcal vaccine can be given at any time during the year and can be given at the same time as influenza vaccine.
  • A single dose of pneumococcal vaccine is recommended for most adults age 65 years and older. Some individuals who were younger than 65 when they received the vaccine may need a second dose at age 65.
  • In the US, only 56 percent of non-institutionalized adults 65 years of age or older and fewer than 20 percent of adults in other high-risk groups who are recommended for pneumococcal vaccine have received it.

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