...a recent finding from a randomised trial in Guinea-Bissau: providing early measles vaccine at 4.5 and 9 months of age compared with the recommended measles vaccine at age 9 months reduced overall mortality from 4.5 to 36 months of age by astonishing 49%.The HDSS sites already collect data on mortality, and mortality would be the main outcome, but we also aim to identify other relevant comparable o ...