Pneumococcal disease is the leading cause of serious illness in children and adults around the world. The disease is caused by streptococcus peneumoniae, a common bacteria that is the leading cause of bacterial pneumonia, and which can also lead to other conditions, including middle ear infection, meningitis and bacteremia.

A single dose of the pneumococcal polysaccharide vaccine can protect against 23 types of the bacteria, which account for over 90% of all invasive pneumococcal diseases in adults. The vaccine's spillover effects are even greater, since pneumococcal disease can lead to coronary heart disease (CHD)-the leading cause of death worldwide.

Despite the still-ambiguous association between pneumococcal pneumonia and CHD, the connection between infection and atherosclerosis (the thickening of artery walls due to build-up of fatty materials) has been suggested by researchers for many years.

Joseph Alpert of the University of Arizona's department of medicine says infection has long been considered an inciting factor for atherosclerosis. "In fact, atherosclerosis probably starts with some inflammatory process, which could be a virus, an infection or an auto-immune condition. Then you have certain conditions that play into that inflammation, such as high cholesterol, hypertension, diabetes and genetic factors".

Cardiologists are being called on to play a more active role in identifying people who may benefit from pneumococcal vaccination, and perhaps administering it as well.