Four people died last week as a result of complications after contracting the West Nile virus, bringing the death toll across Greece from the beginning of the year to 31, according to authorities.
According to a weekly report issued by the Hellenic Center for Disease Control and Prevention (KEELPNO), reported cases reached 271 over on Satuday.
Twenty-one patients are in hospital, including 14 who are in intensive care units.
The virus, which is transmitted by mosquito bites, can affect the nervous system and cause meningitis, encephalitis and other serious complications.
It was first detected in Greece in 2010.