The Health Ministry reports that the number of West Nile fever cases in Israel has doubled over the past week, reaching 300. Since the outbreak began, 15 patients with this diagnosis have died, including four in the past week.

West Nile fever, long known in Israel, is caused by a mosquito-borne virus. The disease is not transmitted from person to person.

Some 80% of those infected are asymptomatic, while 20% experience symptoms of varying severity, including fever, general malaise, headaches, and generalized body pain.

Neurological complications occur in less than 1% of cases. The highest risks are present in the elderly and those with weakened immune systems.