Pneumococcal vaccination resulted in 'herd immunity' among young adults
The introduction of the pneumococcal conjugate vaccine into the infant schedule has resulted in a reduction in invasive disease and the development of herd immunity among young adults, say UK researchers.
UK researchers analysed data on laboratory-confirmed invasive pneumococcal disease cases in infants aged less than 90 days in England and Wales, covering the period July 1998 to June 2010. Invasive pneumococcal disease was defined as identification of S.pneumoniae through culture.
Prior to introduction of the conjugate vaccine (PCV7) in the period 1998-2006, there were 480 confirmed cases of invasive pneumococcal disease in infants under 90 days, amounting to an estimated annual incidence of 13.0 per 100,000 live births. The introduction of the PCV7 resulted in an 83% reduction in the incidence of PCV7 invasive pneumococcal disease, with only six cases in 2009 to 2010.
What does it mean for GPs?
The authors concluded that young adults have benefited from indirect (herd) protection. They concluded: ‘PCV7 introduction has resulted in a significant reduction in PCV7 invasive pneumococcal disease and a reduction in overall invasive pneumococcal disease in young infants.’