By Lydia O’Kane
The quarantine measures were put in place after a 19-year-old migrant who gave birth in a hospital in Athens was found to be infected with the Covid-19 virus. Following the discovery, 63 migrants were tested, and 20 were found to be positive.
14 Day quarantine
Greek authorities said the Ritsona camp, which is located to the northeast of Athens, and hosts 2,500 people, would be quarantined from Thursday for 14 days, during which time nobody could go in or out.
Meanwhile, an asylum seeker living in an apartment in Kilkis in northern Greece was also found to be positive for the Coronavirus.
Risks of Covid-19 to migrants
Humanitarian agencies have been warning about the risks posed to migrants from Covid-19.
They point out that, with thousands of migrants packed into camps, it is hard for them to maintain social distancing. They also migrants lack good factual information on preventative measures.
Thousands of migrants and asylum seekers fleeing war and poverty have arrived in Greece, with more than 40,000 asylum-seekers stuck in overcrowded refugee camps on the country's islands.
Aid organisations have deplored the dire conditions at these facilities which have been described as a "ticking health bomb".
Greece has reported 1,415 cases of the Coronavirus to date, and fifty people have died as a result of the outbreak.