Climate change causes faster spread of infectious diseases, WHO warns

[Simon]

As we all know, climate change is a serious threat to human health and well-being. The World Health Organization (WHO) warns that one of the consequences of a warmer and more unstable climate is the increased spread of vector-borne diseases, such as dengue fever, malaria and Zika virus.

One example of how climate change has contributed to a dengue fever outbreak is Bangladesh, where over 1,000 people died from the disease in 2019. Researchers have linked the unusually high number of cases to irregular rainfall and high temperatures that created favorable conditions for mosquito breeding.

According to WHO, dengue fever is the fastest growing vector-borne disease in the world, with a 30-fold increase in cases over the last 50 years. In 2019, more than 400 million people were infected with dengue fever, and over 4,000 died. The disease causes high fever, severe headache, joint and muscle pain, and sometimes bleeding. There is no specific treatment or vaccine for dengue fever.

WHO’s alert and response director Abdi Mahamud has called the increasing number of severe outbreaks a “canary in the coalmine of the climate crisis” and warned that “more and more countries” are experiencing “the heavy burden of these diseases.”

Climate change affects the distribution and abundance of the mosquitoes that carry dengue fever, as well as their breeding sites and biting habits. Higher temperatures shorten the incubation period of the virus in the mosquitoes, making them more infectious. More frequent and intense rainfall creates more stagnant water where mosquitoes can lay their eggs. Changes in wind patterns and sea level rise can also alter the geographic range of the mosquitoes.

The organization calls for urgent action to reduce greenhouse gas emissions, strengthen health systems, improve surveillance and prevention, and raise awareness among communities.