The victims were reportedly in close contact with Vietnam's 34th case, a 51-year-old Vietnamese female returning home on March 2 from the United States with transit in Qatar. They are a 64-year-old helper, a 37-year-old staff member and the 28-year-old daughter-in-law of the 34th case.

The new cases brought the total infections in Binh Thuan to four, which are all being treated at the General Hospital of Binh Thuan province.

So far Vietnam has recorded 38 infected cases, 16 of which have been discharged from hospital. It saw 22 new infections, among which over 10 are foreign tourists, within the recent six days since Friday.

The country has 113 suspected cases with nearly 25,000 being put under quarantine as of Wednesday, according to its health ministry.

Vietnam has announced its temporary suspension of visa waiver program for nationals of South Korea, Italy, Britain and seven European Union countries of Denmark, Finland, France, Germany, Norway, Spain and Sweden in a bid to curb the spread of the virus.