Three people infected with the West Nile virus died of complications related to the illness this summer, Greek authorities said on Friday.
All cases were reported in August and all victims were over 70 years old, the national Center for Disease Control and Prevention (KEELPNO) noted.
A total of 37 cases -the most recorded in a single year-, have been detected in 2017, including a patient who is still in hospital in intensive care.
In most cases, patients suffered from mild symptoms. It was mainly elderly patients with other chronic illnesses who faced severe complications, according to KEELPNO.
The West Nile virus was first detected in Greece in 2010, when 262 confirmed cases of the disease were recorded, among them 35 fatal. No cases were recorded in 2015 and 2016.
KEELPNO advised the public to take measures to protect themselves against mosquitoes which can transmit the dangerous virus.