Travelers enter Macao through a border port, June 7, 2021. (CHEONG KAM KA/XINHUA)

HONG KONG – Hong Kong residents who have been to Macao in the past 14 days will not be eligible to return to the city via the Return2hk Scheme, meaning that they need to instead undergo a 14-day home quarantine upon arrival in Hong Kong.

Macao entered a state of “immediate prevention” from 3:30 pm on Tuesday after the gambling hub discovered four COVID-19 patients who had lived in the local community for at least a week.

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Under the state of immediate prevention, proof of a negative nucleic acid test result obtained within 24 hours is necessary for departure from Macao. Travelers between Macao and Zhuhai are required to have negative results issued within 12 hours of departure. 

People who have stayed in Macao on the day of arrival in Hong Kong or during the 14 days before that day will be subject to a 14-day compulsory home quarantine, the Hong Kong government said

In a statement issued late Tuesday, the Hong Kong Special Administrative Region government said it would include Macao on the list of “at-risk places” from Wednesday in light of Macao’s latest COVID-19 epidemic development.

“People who have stayed in Macao on the day of arrival in Hong Kong or during the 14 days before that day will not be eligible to return to Hong Kong via the Return2hk Scheme,” the statement read.

They will be subject to a 14-day compulsory home quarantine and must undergo compulsory testing on the third, seventh, 12th, 16th and 19th days of arrival in Hong Kong.

It added that the shortened quarantine period to seven days will also not apply to fully vaccinated people.

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Mass testing in Macao

The four new cases in Macao involved a family of four, who all tested positive to the Delta variant, according to Novel Coronavirus Response and Coordination Center of Macao.

The daughter in the family left Zhuhai for Xi'an in northwest China's Shaanxi province on July 19 for an exchange tour. An earlier China Southern Airlines flight undertaken by the same plane from Nanjing to Zhuhai had two passengers later confirmed as infected and the duo could be the source of the infections in the family, the center said.

The father was a 51-year-old driver for the government and had traveled to Zhuhai and Zhongshan. The mother, 43, worked at a fruits store. The parents had been vaccinated while the children had not, the center added.

According to Macao authorities, the girl had already developed symptoms on July 22. Her brother, father and mother started to feel uncomfortable between July 28 and Monday.

All Macao residents are required to take nucleic acid tests starting at 9 am Wednesday. The mass testing is expected to be completed within three days, the center said.

Tuesday's new infections broke a streak of more than a year without any local cases in Macao. Prior to that, Macao had reported a total of 59 confirmed cases, including 57 imported cases and two imported-related cases.