They need to have got the vaccine at least 14 days earlier or recovered from the disease within the past six months, and need to make a health declaration.
Starting Wednesday only those who cannot meet either of the requirements have to furnish negative test results done within 72 hours to enter the city, according to its police department.
But people with symptoms like fever and cough have to compulsorily take the test.
Police will also demand a negative test result if people arrive from very-high risk areas.
The epicenter of Vietnam’s latest Covid-19 wave in July put up 12 checkpoints at its gateways besides more than 300 inside that it removed after basically bringing the pandemic under control and easing social distancing on Oct. 1.