Dozens of medical workers at a Ho Chi Minh City hospital have tested negative for COVID-19 once, after coming into contact with a pregnant Cambodian woman and her mother who illegally crossed the border into Vietnam for a medical examination, according to the municipal Department of Health.

Their illegal entry was uncovered on Monday, Nguyen Tan Binh, director of the health department, said on Wednesday.

The 33-week pregnant woman and her mother boated from Cambodia to bordering An Giang Province in Vietnam on April 20, Binh elaborated.

They made the illegal entry because the pregnant woman was suffering vaginal bleeding and wanted a medical check-up at a Vietnamese hospital.

Both caught a bus to Ho Chi Minh City from An Giang before hailing a motorbike taxi to get to Tu Du, a leading and crowded obstetrics and gynecology in the city and the country.

The two women used Vietnamese IDs for the medical examination registration and hid their Cambodian nationality as well as illegal entry, Binh said, quoting a Tu Du report.

The pregnant woman was hospitalized and diagnosed with placenta previa, which occurs when a baby's placenta partially or totally covers the mother's cervix.    

During their check-up, hospital staff found out the two’s real identity and illegal migration so they sent them to a quarantine ward, as Vietnam requires all arrivals from outside the country be quarantined to prevent COVID-19 spread.

The hospital has identified 39 direct contacts of the two women, who are doctors, nurses, and nurse assistants.

All of them and the two Cambodians have tested negative for the coronavirus once.

Ho Chi Minh City has detected 68 instances of illegal entry since the beginning of this year, Binh revealed.

The Ho Chi Minh City Center for Disease Control has recommended that medical centers and private clinics keep a close eye on border jumpers coming for medical check-ups.

“There are patients who have illegally entered Vietnam, using public transportation or hiring private cars to visit medical facilities in Ho Chi Minh City,” the center said in a statement.

“The health sector warns medical facilities, including small clinics, and the people to keep vigilant against instances of illegal entry and timely deal with them in accordance with regulations.”

Those living in Cambodia and wanting to come to Vietnam for medical examinations are required to adhere to regulations on entry and quarantine to prevent COVID-19 transmission, the center added.

Entrants who have completed their mandatory quarantine and tested negative for COVID-19 can then go on to use the medical services they are looking for.

Vietnam has logged 2,865 COVID-19 patients, including 1,571 locally-transmitted cases, since the pathogen first struck it on January 23, 2020, according to the Ministry of Health’s data.

The Southeast Asian country has gone 33 days without detecting any community transmission.

Recoveries have reached 2,516 while 35 patients have died, most having suffered critical pre-existing conditions.

The government has urged everyone to stay on high alert as the virus is taking a toll on its neighbors Cambodia, Laos, and Thailand.

Fireworks displays originally meant to celebrate Reunification Day (April 30) have been canceled around Vietnam.

The number of COVID-19 cases in Cambodia has surged to over 11,000, with daily spikes recorded in the hundreds, while its deaths have risen to 82, according to statistics.

Thailand’s tally has mounted to almost 60,000, with more than 160 deaths, whereas Laos has locked down its capital to prevent transmission.

Vietnamese border jumpers have been discovered sneaking into Vietnam from Cambodia to dodge obligatory quarantine over the past few weeks.