Warming temperatures, alternating periods of drought and deluges, and ecosystem disruption have contributed to more widespread outbreaks of infections like malaria, dengue fever, tick-borne encephalitis, and diarrheal illnesses. People living in poverty will be hardest hit by the global surge in infectious diseases.
Warning signs today:
- Disease-carrying mosquitoes are spreading as the climate allows them to survive in formerly inhospitable areas. Mosquitoes that can carry dengue fever viruses were previously limited to elevations of 3,300 feet but recently appeared at 7,200 feet in the Andes Mountains of Colombia. Malaria has been detected in new higher-elevation areas in Indonesia and Africa, posing new risks to millions of impoverished people whose health is already challenged.
- Heavy rainfall events can wash pathogens from contaminated soils, farms, and streets into drinking water supplies. An outbreak of diarrheal illness in Milwaukee in 1993 which affected 403,000 people was caused by the parasite Cryptosporidium, which washed into the city's drinking water supply after heavy rains.
- Higher outdoor temperatures can cause increased outbreaks of foodborne illnesses such as salmonella, which reproduces more rapidly as temperatures increase. Another foodborne bacteria, Vibrio parahaemolyticus, once native to subtropical regions, has expanded its range as far north as Alaska, where in 2004 it sickened unlucky cruise ship passengers when they ate raw local oysters.
What actions will you take for a better earth?