"The risk of Covid-19 transmission from outside the country is very high," Health Minister Nguyen Thanh Long said Tuesday at an online conference to discuss stepping up measures against the Covid-19 pandemic in the "new normal" period.

Vietnam, with its population of 96 million, has gone 81 days without new community transmissions even as the pandemic situation worsens in other places. Many European countries are re-imposing lockdowns to contain new Covid-19 outbreaks.

"The population of infected patients in other countries is very high, so preventing Covid-19 infections has become much more difficult. If the Vietnamese health system was placed in the same context as those countries, it would be difficult for us to meet the treatment needs," Long stressed.

The rising number of illegal entrants is posing a major threat to the country's anti-Covid-19 fight, Long said.

So far this year, over 20,000 people have illegally entered the country. On Monday alone, 77 illegal entrants were discovered in the northern region.

Major General Nguyen Duc Manh, deputy commander of Vietnam Border Guard, said that the tricks deployed to enter the country illegally are becoming increasingly sophisticated. Some people have even counterfeited documents to prolong their stay in Vietnam or stayed illegally in hotels and rented apartments, Manh said.

For instance, some workers from Laos who didn't want to be quarantined entered the country illegally through open trails while workers from Brunei did so via sea routes, not making health declarations or being quarantined, as mandated.

Another complication is that of Vietnamese people leaving and re-entering the country illegally from neighboring countries (China, Laos, Cambodia, etc.) and escaping quarantine.

"They contact each other with unregistered SIM cards (that can be trashed after use) and then rent motorbike taxis or taxi cabs to illegally enter Vietnam. In some cases, they hide in cargo ships, fishing vessels and container trucks to enter Vietnam," he added.

Manh said that the fight against the pandemic was going to take a long time, and the number of illegal entrants, which is expected to increase, exacerbates the problem.

A rising number of Chinese illegal immigrants sneaking into Vietnam to gamble or work have been caught recently. In August, a Chinese man who illegally entered HCMC was confirmed positive for the novel coronavirus and deported after recovering.

Vietnam closed the doors to foreign nationals on March 22 and suspended international flights on March 25. It only allows Vietnamese nationals and foreigners who have diplomatic or official passports or are experts or high-skilled workers to enter the country now.

Another problem increasing the risk of further outbreaks is lax management at quarantine facilities in screening and isolating people, especially hotels, Long said.

He said frozen foods imported into Vietnam from pandemic-stricken countries must be tested for Covid-19, given the virus' ability to survive on the surface of frozen food for a long time.

China, once the epicenter of the coronavirus, is now concerned that imports of frozen foods could spread the novel coronavirus, and has rolled out mass-testing campaigns.

With aggressive tracing and mass testing, Vietnam successfully contained the second Covid-19 outbreak that hit the country last July after more than three months without community transmission.

Vietnam's Covid-19 tally stands at 1,316 now, with 35 deaths.