The four, aged between 27 and 48, have been treated at the National Hospital for Tropical Diseases in Hanoi.

Two women coming back from Kuwait were admitted to hospital on June 27 while the European returnees were hospitalized on June 19.

Doctor Quach Duy Cuong, from the hospital’s Department of Viruses and Parasitology, said their treatment proved brief thanks to early detection and response.

All those entering Vietnam from abroad are sent to centralized facilities for mandatory 14-day quarantine, during which they will be tested at least twice for the new coronavirus.

With their recovery, Vietnam now has 15 active Covid-19 patients left.

The nation has so far recorded 355 cases and no deaths. It has gone 77 days without community transmission.