Age appears to be a key risk factor for pneumococcal disease, with babies, toddlers and older adults being at greatest risk. Among adults, the risk of pneumococcal infection in England and Wales increases from approx. 50 years old. The second peak occurs in adults over 75 years of age, at a rate of 40 cases per 100,000 (similar to the rate in infants).

Invasive pneumococcal disease incidence rate per 100,000 population by age grouping England and Wales, 1996-2005

For invasive pneumococcal disease (IPD), data from the Health Protection Agency (HPA) show that the oldest and youngest are at the greatest risk. Similarly, the case-fatality index for bacterial meningitis increases with age. What’s more, mortality from pneumococcal meningitis in England is 20-30%, despite highly effective antibiotic therapy and modern intensive care facilities.

Social and environmental factors can also affect the likelihood of getting pneumococcal disease. These include: ethnicity, poverty, exposure to cigarette smoke, family size, nursery attendance, and not being breast-fed.

At-risk groups

A number of underlying medical conditions increase the risk of pneumococcal infection, irrespective of age. These include:

• Asplenia or dysfunction of the spleen
• Chronic respiratory disease
• Chronic heart disease
• Chronic renal disease
• Chronic liver disease
• Diabetes
• Immunosuppression
• Individuals with cochlear implants
• Individuals with cerebrospinal fluid leaks

People in any of these at-risk groups should be immunised with the pneumococcal polysaccharide vaccine (PPV). For more information about pneumococcal vaccines click here.

Key points

• Babies, toddlers and older adults are at greatest risk of pneumococcal disease
• A number of underlying medical conditions also increase the risk of pneumococcal infection, irrespective of age