 - The geolocation of the childs address will locate places where he lives. Spatio-temporal data from Sentinel Network, collected since 1984, will provide access on the following viral exposures: seasonal influenza, viral diarrhea mostly enteroviral, mumps, measles, chickenpox. If the defect of our approach is that it does not see real viral infections experienced by children, but only the level of exposure to which they were exposed according to their address, the advantage is an objective spatio-temporal description of virus epidemics around children, making it more or less likely infection of these. Only France has such Sentinel data. 