Shanghai keeps one step ahead of virus

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."