Pneumococcal disease includes a wide range of infections caused by different types of pneumococcus bacteria (Streptococcus pneumoniae).
These bacteria are the most common cause of pneumonia, a serious illness which can affect people of any age. In the UK, 5-11 adults out of every 1,000 get pneumonia every year, and around 40,000 people a year are hospitalised with pneumococcal pneumonia. Even with the use of antibiotics, pneumonia still causes death in up to 20% of cases. Worldwide, pneumonia is the leading cause of death in children. The World Health Organization estimates that pneumonia kills 1.1 million children under the age of 5 every year, and accounts for nearly 1 in 5 of all child deaths. It is estimated that at least two thirds of all cases of bacterial pneumonia are caused by Streptococcus pneumoniae bacteria.
Certain types of pneumococcus bacteria can also infect normally sterile areas of the body such as the blood and the brain. This is called invasive pneumococcal disease, and causes life-threatening diseases including septicaemia (blood poisoning) and meningitis. Around 15% of children with pneumococcal meningitis die, and 25% will have severe, lasting effects, including loss of hearing, loss of sight, learning and language disabilities, or seizures. Invasive pneumococcal disease particularly affects very young babies, elderly people and those with weakened immune systems. People with cochlear implants, cerebrospinal fluid (CSF) leaks, skull defects or fractures of the skull can sometimes get repeated infections.
Pneumococcal disease can also cause ear infections (otitis media) and sinusitis.
In the short film below, Dr Andrew Prendergast talks about pneumococcal disease and why it is important to vaccinate against the disease.
Sam Willis had pneumococcal meningitis when he was 9 months old, before the vaccine was available. In this film, made when Sam was 11 years old, his father talks about the lasting effects of the disease and the impact on the whole family.
These are the most serious symptoms of pneumococcal disease:
It is spread by water droplets coughed into the air by an infected person. The number of cases peaks in winter each year, because people tend to be in closer contact with each other for longer periods, and this spreads the disease more quickly. It is also possible that common viral infections in winter make people more susceptible.
Some types of pneumococcal bacteria can be carried in the back of the throat without causing any symptoms.
Before the introduction of childhood pneumococcal vaccination, one child in every 200 in the UK was admitted to hospital for pneumococcal pneumonia during the first five years of life.
In 2006 the PCV was introduced to the UK schedule. In the first 30 months of that programme, it is estimated that the vaccine prevented around 1,000 cases of invasive pneumococcal disease, and saved around 50 lives. The first vaccine, introduced in the UK in 2006, covered 7 types of pneumococcal bacteria and these 7 types are almost never seen in young children today. A new vaccine covering 13 types replaced the first one in 2010 and the further 6 types have now started to disappear.
However there are many other types of pneumococcal bacteria that can cause infections; the adult vaccine, PPV, protects against 23 types of pneumococcal bacteria. This vaccine does not work in babies because their immune system is immature. There is therefore a need for improved vaccines to protect children against more types of bacteria.
The PCV vaccines, which are given to young children, have been successful in significantly reducing the number of cases of pneumococcal disease in the UK, but it remains a major cause of serious disease. Every year there are 5,000-6,000 cases of invasive pneumococcal disease (meningitis and septicaemia), and around 40,000 hospitalisations due to pneumococcal pneumonia in children and adults. Many of the types which cause invasive disease are becoming resistant to antibiotics.
Read how pneumococcal disease affected one family before the introduction of the vaccine.