Today both France and Spain (two badly hit countries) have come out with seroprevalence numbers. (France is a model, paper linked below. Spain was representative sample/survey of 60K; I don't have the paper yet). Both are ~5 percent. If that holds up, that is very very bad news. https://t.co/Tr7sCEXtrT

— zeynep tufekci (@zeynep) May 13, 2020