Officials in Greece on Sunday placed a second migrant camp near Athens under lockdown after an Afghan resident tested positive for the coronavirus, the migration ministry said.
Officials said the camp in Malakasa, some 38 kilometres (24 miles) northeast of Athens, had been placed under "full sanitary isolation" for 14 days, with no one allowed to enter or leave.
A migration ministry source said the Malakasa facility currently shelters over 1,700 people.
The ministry said the 53-year-old Afghan man, who has a prior condition, had personally sought help with virus symptoms at the in-camp medical facility.
He was subsequently taken to an Athens hospital where he tested positive, and his family was quarantined.
A screening of the camp is in process, the ministry said. The ministry said this would involve staff, close contacts of the ailing man and any with suspect symptoms.
The health ministry has ruled out a general screening campaign at the camps, noting that such a process would be costly and impractical given that the situation changes every day.
The first camp outbreak surfaced earlier this week at a facility in Ritsona near Athens where 23 people -- out of more than 2,500 -- have so far tested positive.
In Greek migrant camps, where tens of thousands of asylum-seekers live in dire conditions, regulations had already been announced in March to keep residents in all camps as far from the local population as possible.
Migration Minister Notis Mitarachi has warned that asylum seekers who attempt to break the lockdown will be prosecuted.
Greece is sheltering some 100,000 asylum seekers, mostly in camps and in hotel rooms and flats.
The worst congestion occurs in camps on five Aegean islands near Turkey where there are over 36,000 people for fewer than 6,100 places.
Specialised medical teams have been deployed to the camps and virus isolation areas and inspection points have been set up.
But social distancing is practically impossible as thousands of refugees and migrants jostle in the queues for toilets and showers.
Authorities over the weekend said they had also tested 176 migrants quarantined on the island of Kea near Athens since mid-March after arriving in a Turkish-flagged freighter that ran aground during a storm.
They will be transported to a camp in mainland Greece within the week, the ministry source told AFP.
The country of 11 million has so far registered 73 deaths and 1,735 cases.
Officials said the Malakasa camp outside Athens had been placed under full lockdown for a fortnight after an Afghan man with a prior medical condition sought help with virus symptoms