Yellow fever

Yellow fever was a severe problem in coastal cities, with many deaths following outbreaks. Research in 1900 showed that it is transmitted by mosquitoes, leading to control efforts by targeting mosquito populations.
 Walter Reed United States 1900 Yellow fever

Yellow fever was a severe problem in coastal cities, with many deaths following outbreaks. Research in 1900 showed that it is transmitted by mosquitoes, leading to control efforts by targeting mosquito populations.