Done. The dodo wings are from 23 million years ago, carrying with them a tertiary-period fungi that spreads rapidly and has a lengthy gestation period, rendering mammals sterile without obvious physical symptoms. Scientists notice 17 weeks after your wish, by which time the fungus has widespread colonized mycelium on every continent and infected everyone who is tested. Suicides skyrocket globally as everyone on earth realizes they are witness and participants to the final generation.