Nguyen Thanh Dung, director of the Cu Chi field hospital, on Tuesday said the flight attendant would continue to be quarantined at the hospital for 14 days as per existing Covid-19 control protocol.

Three others infected by the flight attendant have also recovered, and would also be quarantined at their hospitals for 14 days, he added.

Over 3,600 people in the city who had been in contact with the four patients all tested negative for the novel coronavirus, according to the HCMC Center for Disease Control.

The 28-year-old Vietnam Airlines flight attendant had received media scrutiny earlier this month for having breached quarantine protocols at a facility managed by Vietnam Airlines in HCMC’s Tan Binh District. His actions had caused three others to be infected with the virus: an English language teacher, his student and his baby nephew.

The flight attendant was confirmed infected on Nov. 29, while the other three tested positive within the next two days. The new HCMC infections had broken Vietnam's previous streak of nearly three months without a Covid-19 community transmission.

The flight attendant is now under investigation for "spreading dangerous infectious diseases to humans," which carries a jail term of up to 12 years. This is the first time flouting Covid-19 prevention regulations is being treated as a crime in Vietnam.

Vietnam has recorded 1,414 Covid-19 cases so far, 107 still active. Thirty-five have succumbed to the disease, many being elderly patients with underlying conditions.

Since the breach, the country has recorded no community transmission for nearly a month.