Thirty-two people have died of West Nile virus in Israel during this summer’s outbreak, the Israeli Health Ministry announced on Monday.

Overall, 440 people have been diagnosed with the virus since last month.

West Nile virus has affected Israel for years, usually appearing in June through November and not usually infecting large numbers of people.

Eighty percent of those infected do not develop any symptoms, but the rest, especially elderly and immune-compromised people, display flu-like symptoms including fever, general malaise, headaches and general body aches.

Neurological complications will appear in less than 1% of those infected.

This year’s outbreak was first reported in north Tel Aviv, but has since spread to the southern city of Eilat.

People in central Israel and greater Tel Aviv are especially at risk of contracting the disease as the high humidity creates a good breeding ground for the mosquitoes that spread it, according to the ministry.

Israeli authorities have urged health officials to increase mosquito monitoring and extermination efforts, while calling on the public to take preventative measures.