Whilst this study is still running within the hospital we are no longer recruiting patients in the Emergency Department. This is a population based, prospective cohort study of pneumococcal pneumonia in adults following the introduction of the childhood pneumococcal vaccination. The study is investigating whether children who have received the pneumococcal vaccine can pass their immunity on to adults whom they have close physical contact with. It is also looking to characterise the pneumococcal serotypes implicated in pneumonia.