Greece’s Health Ministry yesterday said it was stepping up the fight against West Nile virus which has killed four people since the beginning of the month.

Some 60 people were diagnosed with the virus yesterday, with 13 new cases discovered on Monday, according to a statement from the Centre for the Control and Prevention of Diseases.

So far 60 people have been diagnosed with encephalitis – an inflammation of the brain caused by the virus – while four elderly patients, also suffering from unrelated diseases, died.

According to the centre, eight of the 29 people hospitalised yesterday are in intensive care.

The virus, transmitted through bites by infected mosquitos, has so far affected populations in Greece’s Macedonia region, in a zone stretching from Larissa to the northern city of Salonika, in close proximity to lakes and rivers.

The Health Ministry has ordered that efforts to spread insecticides in the region be intensified, targeting areas where contamination is highest. A campaign to inform the public will also be launched.

A doctor working at the centre, Doritsa Bakka, said the virus has been found in the past in Greece but had never before caused encephalitis.

She said the spread of the disease had been encouraged by a hot and wet summer, an ideal breeding ground for mosquitos.