 In a first sub-study of CHO-CAP, the CAPITA participants are asked, via written information distributed shortly after vaccination, to fill in once-only a short questionnaire describing their health status 5 item EQ-5D instrument and a few additional socio-demographic background data. This is done in order to determine an EQ-5D baseline score index value for health status - a prerequisite to match CAP patients and controls later, and as such an inclusion criterion for the two nested cohorts that will be followed prospectively. 