New Delhi, May 13 : From sporadic outbreaks of Aedes-borne dengue and chikungunya, the European Union is transitioning towards an endemic state, according to a study, published in the Lancet Planetary Health journal.

The principal vectors of dengue virus and chikungunya virus are Aedes aegypti, the yellow fever mosquito, and Aedes albopictus, the Asian tiger mosquito.

In 2024, there were a total of 304 dengue cases in the European region -- a historic peak compared with the combined total of 275 cases in the previous 15 years.

The rising trend suggests the spread of tiger mosquitoes -- that transmit these viruses -- to farther north due to global warming, said the researchers in Sweden and Germany.

The team cited that from being mainly confined to tropical regions once, the virus' frequency and severity of outbreaks have increased since 2010. This is due to 'rising temperatures'.

'Climatic variables emerged as the strongest predictors of outbreak risk, even after accounting for health-care expenditure and imported case numbers,' said the team including from Umea University (Sweden) and University of Heidelberg (Germany).

"Warmer summer temperatures were found to substantially elevate outbreak risk, particularly in urban and semi-urban settings, whereas human travel and mobility were found to facilitate the spread of these two Aedes-borne diseases," they added.

The study is based on an analysis of the spread of the two diseases in Europe over the last 35 years.

According to European Centre for Disease Prevention and Control data, most outbreaks (95 per cent) took place between July and September of 2024, with 64 occurring in the third quarter of the year.

Urbanisation, which provides new habitats for Aedes vectors, also significantly affected outbreak risk, with urban and semi-urban areas having a higher HR for outbreak events than rural areas, said the team.

"Our findings highlight that the EU is transitioning from sporadic outbreaks of Aedes-borne diseases towards an endemic state. The interval between vector establishment and local outbreaks has substantially shortened over the past three decades and is expected to decrease further," the researchers said.

The study underscored the urgent need for robust public health measures, including stringent vector control, enhanced entomological and disease surveillance, citizen science, and early warning systems.

"In the context of a warming climate, mitigating the transition to endemicity will require proactive, vigilant, and well-targeted public health interventions," the team said.

/IANS