WHO: Dengue will spread to southern Europe and US

The World Health Organization (WHO)’s chief scientist has suggested that Dengue fever will become a major threat in the southern United States, southern Europe and new parts of Africa this decade.

The prediction comes as warmer temperatures create the conditions for the mosquitoes carrying the infection to spread.

The illness has long been a scourge in much of Asia and Latin America, causing an estimated 20,000 deaths each year. Rates of the disease have already risen eight-fold globally since 2000, driven largely by climate change as well as the increased movement of people and urbanization.

Many cases go unrecorded, but in 2022 some 4.2 million cases were reported worldwide and public health officials have warned that near-record levels of transmission are expected this year.

Indeed, Bangladesh is currently experiencing its worst-ever outbreak, with more than 1,000 deaths.

Farrar said the infection is likely to take off and become endemic in parts of the United States, Europe and Africa – all regions where there has already been some limited local transmission – as global warming makes new areas hospitable to the mosquitoes that spread it. That will put acute pressure on hospital systems in many countries, he warned.

Dengue is spread by infected Aedes aegypti mosquitoes, which behave differently to the malaria-carrying kind. For example, they bite people indoors, and they bite all day rather than overnight. They also breed in very shallow water.