Several supermarkets and convenience stores staying open during Tet, the Lunar New Year festival, have seen an unusual surge in people buying medical and antibacterial masks, staff at these outlets said.

The Aeon Mall supermarket chain in Hanoi has attracted large numbers of visitors and shoppers during the holiday that lasts until January 29. Of these, many people visited the face mask stall located at the entrance of the outlets. It has been among the most popular stalls, next to the fresh food and vegetable stalls.

Hong Anh, a Hanoi resident, said she was looking for a mask at the stall ever since news broke a few days ago about the virus spreading to Vietnam. Many drugstores that sell medical and antibacterial masks were closed for Tet, so she went to the retail store to buy masks for the whole family.

"There is a range of facemasks at different prices to choose from. At this time spending a few hundred thousand dong (VND100,000 = $4.3) to buy a good mask is not too expensive because there are still no vaccines against the virus, preventive steps are needed," Hong Anh said.

Quang, another Hanoi resident shopping for masks for his family, shared similar concerns.

"In a few days my children will go to back to school after Tet, so I’m looking for medical masks for them and other adults to wear to school and work," he said.

Vietnam confimed the first two cases of nCoV pneumonia infection last Thursday, the first day of the Tet holiday. The Chinese patients, father and son, have been quarantined at the Cho Ray Hospital in HCMC for treatment.

The new coronavirus (nCoV) was first detected in China’s Wuhan City last December.

While the prices for antibacterial masks at supermarkets remain stable, ranging from VND17,000-70,000 ($0.7-3) depending on the type, online sites are also selling these like hot cakes, with prices fluctuating depending on the product and the quality claimed.

After posting a mask for sale on a Facebook group, Huyen has received a few dozen orders for the 3D Unicharm masks, a Japanese product. She claims this is the most virus-resistant type that can prevent effects of environmental pollution and keep out particle dust.

It costs VND240,000 ($10.4) per box of 100 pieces. Meanwhile, the N95 mask of a US-based company called 3M costs VND22,000 ($0.95) each and can be used five times. The product is said to have at least 95 percent filtration efficiency against certain non-oil based particles.

Ngoc, another online seller who has offered the same products an hour earlier, was selling them for higher prices at VND270,000 ($11.7) and VND90,000 ($3.9) respectively.

On Sunday, the Da Nang Hospital quarantined 12 people with high fever for coronavirus infection tests, which made Tinh, a resident of the central city of Da Nang, increasingly nervous.

"Living in central Vietnam I have no choice but to force everyone in the house to use a mask when they leave the house." She has ordered five boxes of Smart masks imported from Singapore for four family members, each box costing VND300,000 ($13).

Several doctors say that a 3-layer medical mask can prevent the coronavirus so there is no need to buy masks that are too expensive. The virus weakens at temperatures above 20 degrees Celsius, especially when it gets above 25 degrees Celsius with high humidity.

Doctors also recommend keeping houses well-ventilated and keep room temperature above 25 degrees Celsius.

So far, apart from Vietnam, the virus has spread from mainland China to Thailand, South Korea, Japan, Taiwan, Macau, Hong Kong, the U.S., Singapore, Malaysia, France and Canada, infecting more than 2,500 people.

In Vietnam, as of Sunday afternoon, of patients suspected of carrying the new pneumonia virus, two (the Chinese patients, father and son) have tested positive, 22 negative and 35 are awaiting results, according to Ministry of Health data.