I n close-up, the black and white markings of Aedes albopictus are quite striking, but the ‘tiger mosquito’ can be deadly and is one of two insects behind the rapid rise of dengue fever across the globe. Since 2021, cases of dengue, also known as ‘break-bone fever’ due to the body aches it causes, have doubled each year. Between January and September 2024, there were more than 12.
7 million cases in total – almost double the 6.5 million cases reported in 2023 – as well as 8,791 deaths, according to the World Health Organization (WHO). The vast majority of cases were reported in the WHO’s Americas region, cases are now starting to climb in the Eastern Mediterranean and European regions – and the virus is now endemic in more than 130 countries.
In October, the WHO’s Director-General Tedros Adhanom Ghebreyesus warned the spread was “an alarming trend that demands a coordinated response across sectors and across borders”. It’s thought that more than 4 billion people, or around half the world’s population, are currently at risk from mosquito-borne infections , including dengue, Zika and chikungunya, which are known as arboviruses – and this is estimated to rise to 5 billion by 2050. Originally native to the tropical and subtropical climes of Southeast Asia, the tiger mosquito has spread worldwide as global temperature rise has enabled its habitat to expand.
The mosquito species is also highly adaptable, and its eggs can survive frost, allowing it to surv.