All the three tested positive for SARS-CoV-2, which causes the disease, while in quarantine and are being treated at the Khanh Hoa Hospital of Tropical Diseases.
As of 6 am on November 6, a total of 1,069 COVID-19 patients in Vietnam had recovered. There are no patients in critical conditions, and the death toll remains at 35.
Among the active patients, 18 have tested negative once for the coronavirus, seven twice and five thrice.
Vietnam has entered the 65th straight day without locally-transmitted cases.
As many as 14,064 people who had close contact with COVID-19 patients or came from pandemic-hit areas are now under quarantine nationwide.