This 2003 photo shows a female Aedes albopictus mosquito acquiring a blood meal from a human host. Dengue, a tropical illness caused by a virus, is spread by Aedes mosquitos, a type of warm weather insect that is expanding its geographic reach because of climate change, experts say.
The World Health Organization declared an emergency in December, and Puerto Rico declared a public health emergency in March. Dengue is caused by a virus spread by a type of warm weather mosquito that is expanding its geographic reach because of climate change, experts say. “We’re currently seeing is increases in the cases due to dengue 2 and dengue 3, for which the population has very little immunity,” said Dr. Gabriela Paz-Bailey, the Puerto-Rico-based chief of the CDC's dengue branch.Vaccines have been tricky. U.S. officials in 2021 recommended one vaccine, made by Sanofi.
Across the world, more than 6.6 million infections were reported by about 80 countries last year. In the first four months of this year, 7.9 million cases and 4,000 deaths have been reported, according to the World Health Organization. It's been particularly— about 3,000 cases last year in U.S. states and territories. But it was the worst in a decade, and included more infections that occurred locally, courtesy of native mosquitoes. Most were in Puerto Rico, but about 180 were in three U.S.