Contact tracing and isolation proved to be the key tools to contain the spread of coronavirus as it reduced the period during which the cases remained infectious in the community, said a study. A retrospective Lancet study analysed the epidemiology and transmission of COVID-19 in 391 cases and 1286 of their close contacts in Shenzhen, China to find the impact of measures taken by authorities.
Researchers found out that contact tracing and isolation helped reduce the basic reproduction number (R0) of the infectious disease. However, they opined that the overall impact of isolation and contact tracing is uncertain and highly dependent on the number of asymptomatic cases.
“Children are at a similar risk of infection to the general population, although less likely to have severe symptoms; hence they should be considered in analyses of transmission and control,” the study added.
The Shenzhen Center for Disease Control and Prevention had identified 391 COVID-19 cases and 1286 close contacts from January 14 to February 12, 2020. The researchers compared cases identified through symptomatic surveillance and contact tracing and estimated the time from symptom onset to confirmation, isolation, and admission to hospital.
“Data from the early phase of local outbreaks, when detailed contact tracing is possible and sources of infection can still be reliably inferred, are particularly powerful for estimating critical values pertinent to describing transmission and the natural history of a disease,” the report concluded.
While China has been able to flatten the curve to contain highly infectious disease through isolation and contact tracing, the virus has spiralled out in the United States. It has reported over a million cases, one-third of the worldwide cases, and nearly 57,000 deaths due to the infectious disease. According to the latest report, over three million coronavirus cases have been confirmed worldwide with over 212,000 deaths, overwhelming the health care facilities across the globe.
(Image credit: AP)