On Sunday, doctors called on the European Union to abide by the immigration agreement with Turkey, and to transfer asylum seekers from the camps to safe places, due to the spread of the coronavirus.
This came in an open call published by two Dutch doctors, Saint van der Koch and Stephen van de Vijver, on the Sosmoria website.
Until 12:10 GMT, 5,024 doctors had signed the call and received support from 25,313 people.
"The refugee camps of Greece host more than their capacity, which will bring the disaster to Europe," the call said.
It indicated that Moria refugee camp on the Greek island of Medelli hosts more than 40,000 asylum seekers and only has a limited number of doctors.
"Ignoring this situation would be a serious violation of European health values," added the call.
According to the website, the European Union did not abide by the immigration agreement signed with Turkey four years ago, as it did not receive its share of asylum seekers as stipulated in the agreement.
The doctors continued: "Gathering asylum seekers in the camps on the Greek islands is not a solution."
They called on European Union leaders to abide by the immigration agreement with Turkey, and to transfer asylum seekers to safe places, within the continent.
On 18 March 2016 Turkey and the European Union reached three mutual agreements on immigration, the readmission of asylum seekers and the cancellation of entry visas for Turkish citizens.
Ankara has complied with its obligation regarding the first two agreements, while Brussels has not cancelled the entry visa for Turks.