The HCMC Department of Health confirmed Friday that the two relapsed patients are "Patient 124," a 52-year-old Brazilian man, and "Patient 235," a 25-year-old British man, linked to Buddha Bar & Grill in District 2, the city’s largest coronavirus hotspot.

They were found positive for the novel coronavirus 15 days after being discharged from the city’s Cu Chi Field Hospital.

The Brazilian man, who attended a party at the Buddha Bar on March 14, was confirmed positive on March 23. He was discharged on April 14 after three negative tests and asked to quarantine himself at home for another 14 days.

On April 29, he had his samples taken for testing for the last time before completing the 14-day home quarantine. However, the result came back positive.

The British man, who visited the Buddha Bar the same day, was confirmed positive on April 3 and discharged on April 15. He was also asked to be quarantined at home for another 14 days. On April 30, health officials took his samples for the final test and the results came back positive for the novel coronavirus.

Both men are back at the Cu Chi hospital for treatment.

So far, the city has reported six relapses, five of them related to the Buddha Bar and the other a Vietnamese student returning from France.

The the new relapses, the number of patients under treatment in Vietnam has risen to 53. 217 others have been discharged.

In the wake of the relapses, HCMC health authorities announced Friday that they will keep recovered Covid-19 patients under health monitoring for 30 days instead of 14. During this period, the city will conduct the new coronavirus test every day on the recovered patients.

In another move to prevent possible infections from relapsed patients, the Health Ministry last week suggested that patients eligible for discharge from hospitals spend the additionally mandated quarantine period of 14 days at the hospitals, instead of at home.

The ministry has also said that samples taken from five of the relapsed patients showed the virus was "inactive" in their bodies, which theoretically means the chances of them spreading the infection are "very low."

Covid-19 relapses are not uncommon worldwide as it has also been reported in China, Japan and South Korea.

In South Korea, where more than 270 people have tested positive for the virus after recovering, researchers at the country's center for disease control and prevention have said it is impossible for the virus to reactivate in human bodies and the relapse results were due to testing failures.