The year that looked like nothing
Rain brings mosquitoes, everyone knows that. Brazil's first urban yellow fever outbreak in decades came with no rain at all.
The drought was worse than a once-a-century one. New simulations in Science Advances say the dryness did the work by moving things: forest primates walked into cities looking for water, and mosquitoes bit more because dehydration scared them more than people did. The virus was already there. The empty year is what made it travel.
The year that looked like nothing was the year everything moved.