The two Indian men, aged 41 and 34, were passengers on IndiGo flight 6E9471 that landed in HCMC's Tan Son Nhat airport on October 6.

Test results from the third time their samples were taken returned positive for the novel coronavirus Monday. "Patient 1170" and "Patient 1171" are being treated at the Sa Dec General Hospital in the southern province of Dong Thap.

Eighteen passengers on the same IndiGo flight were confirmed positive for virus earlier. They are still in hospitals in the southern localities of Dong Thap, Dong Nai and HCMC.

"Patient 1172" is a 22-year-old Hanoi resident who returned to Vietnam from France on Vietnam Airlines flight VN5010 that landed at HCMC's Tan Son Nhat on October 21. He was quarantined on arrival in the neighbouring province of Ba Ria-Vung Tau. His test results returned positive on Monday.

Six other passengers on his flight have already been diagnosed with Covid-19.

HCMC on alert

Health authorities in HCMC announced Tuesday that they have tracked down and isolated 38 people in District 2 and District 6 who'd come into close contact with a South Korean expert who tested positive for the coronavirus upon arriving in Japan from HCMC on Saturday.

The South Korean arrived in Vietnam on July 29 and were quarantined in Hanoi. He was in HCMC from September 29.

The group of 38 include colleagues, interpreters and acquaintances. Six of them from Thao Dien Ward in District 2 and one from District 6 have been sent to a centralized quarantine camp, while the rest have been ordered to isolate themselves at home.

HCMC Center for Disease Control said Tuesday night that 29 of the people have tested negative while the results for the other nine have not been available.

HCMC has gone three months without detecting an infection caused by community transmission. The corresponding national streak is 54 days.

In all, Vietnam has recorded 1,172 Covid-19 cases with 1,062 recoveries and 35 deaths. Three patients died after recovering from Covid-19 and were not counted in either groups.

Of the total, 691 were community transmissions.

More than 1.16 million have died of Covid-19 worldwide.