Vietnam’s Ministry of Health on Saturday reported four imported coronavirus cases from Russia, the UAE, and Ukraine.
They are all Vietnamese returnees, with two of them being sailors and arriving in Vietnam aboard a ship from Ukraine, the health ministry said.
The two others returned by plane from Russia and the UAE.
Of the four, one is being isolated for treatment in south-central Phu Yen Province, two in south-central Khanh Hoa Province, and one in central Da Nang.
Vietnam has confirmed 1,395 COVID-19 patient, with 1,238 recoveries and 35 virus-related deaths, according to the Ministry of Health's data.
The country has recorded no community transmission for 11 days in a row, after Ho Chi Minh City detected four patients early this month.
Vietnam began its human trial of a locally made COVID-19 vaccine on Thursday, with 30 volunteers given a shot within the first hour.
The jab will be tested over three phases, with the final one to conclude in August next year.
Should tests go as planned, the vaccine will be manufactured and made available for local residents in late 2021 or early 2022, the producer said.
A shot is projected to cost VND120,000 (US$5) if it passes all human trials and is approved for mass inoculation.
Although most regular inbound commercial flights are now suspended, charter planes to the country have been arranged to bring in experts, skilled workers, and diplomats, and to repatriate Vietnamese citizens stranded in other nations and territories due to the pandemic.