global population at risk today, more than half the world's seven billion people.
number infected. Unlike the mainly nocturnal species that spread malaria, the mosquito that carries the dengue virus bites mostly during the day, increasing risk.
or so severe cases a year.
die each year.
times, the 5-year average today than it was 40 years ago, making dengue fever the fastest growing vector-borne disease.
countries in which dengue has been reported in recent years, before 1970 it was reported in only 9 countries. Rapid urbanization and warming temperatures are expanding its range.