Italy is seeing evidence that rising temperatures and longer warm seasons are helping mosquitoes spread West Nile virus across a wider geographic area and for a longer period of the year, according to health authorities.

More than 650 West Nile virus infections have been reported in Italy so far this year, accounting for roughly half of all cases recorded across Europe, local health authorities said.

Antonino Bella, a researcher at Italy's National Institute of Health (ISS), said warmer temperatures associated with climate change were creating conditions that could accelerate mosquito reproduction and prolong the virus transmission season.

“Higher temperatures linked to climate change help mosquitoes reproduce and extend the transmission season, increasing the chances that infected mosquitoes will spread the virus to people,” Bella said.

West Nile virus has been considered endemic in Italy since 2020, when infections began to increase significantly. Cases are now reported regularly during the summer and early autumn months.

The virus is primarily transmitted to humans through the bites of infected mosquitoes. Most infected people do not develop symptoms, while others typically experience a mild illness resembling the flu.

However, a small proportion of infections can lead to serious neurological complications, including encephalitis and meningitis. Older adults and people with underlying health conditions are considered particularly vulnerable to severe disease.

The increase in cases has renewed attention on the role of changing weather patterns in the spread of mosquito-borne diseases. Longer periods of warm weather can create more favorable conditions for mosquito populations and potentially extend the period during which viruses can circulate.

Italian health authorities continue to monitor West Nile virus activity as the country moves through the late summer and early autumn period. (ILKHA)