36 people were diagnosed with the disease at a Chilean research station. 26 of them were Chilean soldiers and - 10 service personnel. They were evacuated to the city of Punta Arenas in southern Chile.
Three members of the crew of the ship that arrived to help the base also got infected with the virus.
All these countries, with the exception of Denmark, have reported only isolated cases.
Nevertheless, WHO Emergency Relief Coordinator Michael Ryan is convinced that a new version of the virus can be brought under control.
Petrov added that the mutation of the virus occurred naturally.