Public doctors hold different views to Portuguese epidemiologist on NAT

Doctors at the Health Bureau (SSM) yesterday conveyed contrasting opinions to a Portuguese epidemiologist whose interview was published yesterday in a local Portuguese newspaper. 

At yesterday’s daily health press briefing, a Portuguese journalist cited a report from today’s Portuguese paper, Hoje Macau, in which a Portuguese epidemiologist criticized the way that quarantine and nucleic acid testing (NAT) has been used in Macau with the aim of controlling the spread of the Omicron variant of SARS-CoV-2.

According to the Portuguese newspaper: “Manuel Carmo Gomes, epidemiologist and one of the key faces of Covid-19 analysis in Portugal, claimed that carrying out confinement and frequent mass tests do not work with the Omicron variant.”

The epidemiologist suggests that mass SARS-CoV-2 NATs should be used as a tool to diagnose suspicious cases with symptoms, rather than for screening as Macau is doing. He also commented that keeping positive cases in confinement for longer than seven days did not make sense to him.

Macau is quarantining all positive cases, regardless of whether they are symptomatic.

Gomes warned the local Portuguese paper that stopping the spread of the virus is impossible. Even if there is a period of zero new cases, infections will sweep through once again once measures are relaxed.

The panel of officials was questioned as to whether they would consider the epidemiologist’s comments.

A&E doctor Lei Wai Seng, medical director at the public hospital, said that nucleic acid testing is currently the most accurate way to confirm whether a person has contracted SARS-CoV-2. The test is used to identify those who are ill with Covid-19.

“We see that many Omicron cases are simply asymptomatic, but they are still infectious,” the medical doctor said, explaining that this “means that the virus can be transmitted to other people.”

Lei emphasized that the citywide NAT is used as a mechanism to pick out those who have contracted the virus but showed no symptoms, “so that the chain of infection can be cut.”

In order to achieve dynamic zero-Covid, the A&E doctor added, such chains of infection must be eliminated in the community. “Only then can our outbreak be considered under control,” Lei concluded.

The medical doctor also appealed for the protection of fragile groups as another reason to justify the need for mass NAT.

He said that vulnerable groups, such as those with chronic diseases or who are immunocompromised, will have a higher chance of developing severe symptoms if they contract the virus. “Therefore, most of our strategies have a focus on protecting vulnerable groups of people.”

The medical doctor was also asked why some positive cases were not released from confinement even if they had cycle threshold (CT) values above 35. The CT value is used to determine whether a case is considered positive or negative.

In answer to this question, the medical doctor cited a national guideline that the yielding of CT values above 35 in two consecutive NATs facilitates a positive case’s return to the community. “We don’t need a negative result,” Lei said.

He added that, with this guideline, the health agency will not “frequently” conduct NAT on a positive case in the early phase of infection.

Categories Macau