On what basis has the supreme court challenged congress?

You haven't provided a specific case, but if the question is in general, then the supreme court challenges in based on the legislature that the congress passes. The supreme court provides judicial review of the legislature passed by the congress and deems whether or not the legislature is unconstitutional, in which case it can abolish it.

The constant presence of diseases or infectious agents within a given geographic area or population group. it may also refer to the usual prevalence of a given disease with such area or group. it includes holoendemic and hyperendemic diseases. a holoendemic disease is one for which a high prevalent level of infection begins early in life and affects most of the child population, leading to a state of equilibrium such that the adult population shows evidence of the disease much less commonly than do children (malaria in many communities is a holoendemic disease). a hyperendemic disease is one that is constantly present at a high incidence and/or prevalence rate and affects all groups equally. so probably family history.