Extensive contract tracing, isolating cases, and testing may reduce the spread of the novel coronavirus, and favour control of the COVID-19 outbreak, suggests a study carried out in China.
However, the researchers from the Harbin Institute of Technology at Shenzhen, China, caution that the impact of contact tracing to rapidly isolate people who could be infected with coronavirus disease 2019 (COVID-19) depends on identifying asymptomatic cases.
Published in The Lancet Infectious Diseases journal, the study of 391 cases and 1,286 of their close contacts found that contact tracing reduced the length of time people were infectious in the community over 4 weeks in Shenzhen, China.
According to results from In Shenzhen, authorities identified whom to isolate based on their contact with confirmed cases, as well as isolating people who already had symptoms, the researchers said.
The new study found that contact tracing increased the speed at which new cases were confirmed by 2 days -- an average of 5.5 days initially, reduced to 3.2 with contact tracing.
It also reduced the amount of time it took to isolate infected people by 2 days -- from an average of 4.6 days down to 2.7.
There were only three deaths in the study group during the study period, the researchers said.
"The experience of COVID-19 in the city of Shenzhen may demonstrate the huge scale of testing and contact tracing that's needed to reduce the virus spreading," said Ting Ma from the Harbin Institute of Technology at Shenzhe