Shanghai keeps one step ahead of virus

Thousands tested

On Monday, video clips of nucleic acid tests being administered to more than 17,700 cargo workers at Pudong International Airport the previous night went viral.

The tests involved 240 doctors and nurses and 300 workers who helped with preparatory work.

Netizen Xin Zhidu said: "The tests were like a meticulous blanket search for a suspicious infection. We're confident the city, which has a government that people trust, will make it through. Stay strong Shanghai and the world!" The comment received 27,000 "likes".

Epidemiologists said the infections among the airport workers are a reminder that imported non-cold-chain cargo may become a viral transmission route in winter.

Zhou Junlong, vice-president of the Shanghai Airport Authority, said strict cargo disinfection, standard loading and unloading procedures and protection for key workers will be strengthened at cargo handling facilities.

Pan Hao, deputy head of Shanghai's front-line COVID-19 work team, said epidemiological investigation tracing for the cases reported in the past week was expanded from close contacts, and those linked to them, to individuals at the same work site or in the same occupation.

A case reported on Monday was discovered among the nucleic acid test results for the airport cargo workers.

The prompt action taken by the Shanghai authorities has again been impressive. City and district centers for disease control and prevention, or CDCs, have thoroughly screened, located and quarantined individuals related to the latest cases, with their work being clearly defined.

For example, after two cases were reported on Nov 20, the city's CDC said the next day that 91 close contacts, 213 people linked to these close contacts and 15,415 other individuals had been traced. Their initial nucleic acid test results were obtained, and most of those involved were quarantined at designated hotels, while the remainder made their way to quarantine locations.

Pan said that when the medical team members failed to identify the source of infection for the case reported on Nov 9, involving a cargo worker at the airport, they felt frustrated.

Strenuous efforts were made to detect the source through human-to-human or object-to-human transmission vectors－the two channels commonly agreed on internationally.

Pan said, "We later began to look for possible work sites that the two cases (on Nov 20) had been exposed to. We finally identified an aircraft container from North America, which the workers entered without wearing face masks on Oct 30.

"Tests also showed the virus they were infected with was a strain from North America," he said.

Experts said the early detection of infections in the past week also showed that Shanghai's network of 117 fever clinics, where an intelligent system to report suspicious cases has been installed, had played its part.

Wu Jinglei, director of the Shanghai Municipal Health Commission, said, "The system collects and analyzes information concerning cases, helps health authorities and CDCs to predict epidemic development more accurately and enables effective precautionary measures to be taken promptly."