As a result of the greenhouse effect, microorganisms that used to thrive in the tropics are now capable of survival in temperate regions. Contagious diseases that previously only existed in the tropics, such as dengue fever, malaria, and many others, are posing a growing threat to the populations of temperate regions.
溫室效應所及，原本在熱帶繁殖的微生物如今也得以在溫帶生存下來，以往熱帶才有的疫病，像是登革熱、瘧疾等等，如今也逐漸威脅到溫帶居民。