The pneumococcus bacterium (Streptococcus pneumoniae) kills approximately 500,000 children less than five years of age each year, mainly in the developing world. It is the leading cause of childhood pneumonia, the number one killer of children under five in the developing world, and a cause of meningitis (inflammation of the covering of the brain), ear infections, and bacteremia (blood stream infection). Pneumococcal disease can be treated with antibiotics; however, antibiotic-resistant strains are becoming more common worldwide. Current pneumococcal vaccines approved for use in children are effective against strains common in the industrialized world and some developing countries, but do not cover all 90+ pneumococcal serotypes and they are complex and expensive to manufacture. There are several additional vaccines in development.

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Pneumococcal disease

  • The pneumococcus bacterium (Streptococcus pneumoniae) is responsible for approximately 500,000 deaths of children less than five years old each year according to the World Health Organization. It can cause pneumonia, meningitis (inflammation of the covering of the brain), otitis media (inner ear infections), and bacteremia (blood stream infection). Children less than two years old are especially vulnerable to infection and the vast majority of pneumococcal pneumonia deaths in children occur in low-income countries.
  • The bacteria normally are carried in the nose or upper throat and are spread through sneezing, coughing, or being in close proximity with an infected person. Up to ninety percent of children carry the bacteria without showing any signs or symptoms, but they can still infect others.
  • Drugs such as penicillin are generally effective for treating pneumococcal infections, but antibiotic-resistant pneumococcus is becoming more common worldwide. This situation makes prevention of the disease, through widespread use of pneumococcal vaccines, even more important.

Pneumococcal vaccines

  • GlaxoSmithKline Biological's Synflorix™ and Wyeth Pharmaceutical's (Pfizer's) Prevnar 13® are two pediatric pneumococcal conjugate vaccines (PCVs) on the market and offer broader protection against 10 and 13 serotypes, respectively.
  • Pneumococcal polysaccharide vaccines by Merck and Sanofi Pasteur protect against 23 pneumococcal serotypes, but they are recommended mainly for use in adults.
  • Many other vaccine candidates are also in the development pipeline.
  • Current pneumococcal vaccines, even with added strain coverage, do not protect against all 90+ pneumococcal serotypes and they are complex and relatively expensive to manufacture.
  • Pneumococcal protein vaccines are being developed to be more affordable, as well as to potentially protect against most or all of the disease-causing serotypes of pneumococcus.

Related diseases

There are several key causes of childhood pneumonia and meningitis (inflammation of the covering of the brain), including pneumococcus and meningococcus bacteria. Learn more about meningococcus.

In addition, there are a number of bacterial and viral causes of respiratory diseases, all of which can affect the lungs and upper airways, including pneumococcus, respiratory syncytial virus (RSV), and influenza. Learn more about RSV. Learn more about influenza.


Page last updated: August 2016.

Photo: PATH/Ashley Latimer.