Cambodia was suffering a significant surge in Covid-19 community transmissions. On Tuesday, the country reported 181 new infections. Three days earlier, there were more than 1,000 cases.

Tran Dac Phu, senior advisor to the Health Ministry's public health emergency operations center, told VnExpress Tuesday that "the border between Vietnam and Cambodia is really long, not to mention the sea and air routes. It should be noted that controlling travel by sea is truly difficult."

Many Vietnamese people stay and do business in Cambodia and the number of people traveling back and forth, both legally and illegally, is high, he said.

"The infection risk is high and it is essential that we tighten control over border gates and all small paths that people use to enter Vietnam. It is possible that community outbreaks could re-emerge in the country if someone sneaks in illegally with the virus," he said.

The World Health Organization (WHO) in Cambodia has recently warned of the risk Cambodia is facing.

"We stand on the brink of a national tragedy because of Covid-19. Despite our best efforts... new cases occur every day and we are racing against the virus. Unless we can stop the outbreak, Cambodia’s health system is at high risk of being overwhelmed, which would have disastrous consequences," said WHO Representative to Cambodia, Li Ailan.

Just last month, Vietnam had suffered a spate of infections after a group of Vietnamese returned home illegally via the sea route.

Three of them, all women 25 and 26 years old, were confirmed infected after they returned from Cambodia on a fishing vessel that docked at Phu Quoc Island off the nation’s southern coast.

Last December, a man had tested positive after entering Vietnam illegally. He traveled from Myanmar to Thailand by truck and then got into Cambodia on another truck before sneaking into the south of the country. Fortunately, his mother reported him and thanks to her, the infection chain was stopped just in time. Three of the eight people crossing the border with him were also infected.

As per Vietnam's protocols, all people entering the nation from abroad must be quarantined for 14 days, during which they will be tested at least twice.

Illegal entrants are those evading checkpoints to avoid quarantine.

Phu called on the nation's citizens to proactively report to authorities if they come to learn of any person sneaking into the country illegally.

For around three weeks now, Vietnam has not recorded any community transmission but the number of imported cases has been increasing gradually, with many of them returnees from Cambodia.

So far, 1,570 of Vietnam's 2,714 Covid-29 cases have been local transmissions.

Vietnam has inoculated around 60,000 citizens against Covid-19 with the vaccine produced by British-Swedish firm AstraZeneca, obtained either through contracts or global vaccine access mechanism Covax. Most of the vaccinated people so far are frontline workers in the Covid-19 fight.

The nation is expected to start mass production of indigenously produced Nanocovax vaccine in August if a three-phase human trial is successfully completed in May.