US may have seen 35 times more Covid-19 cases if there was no social distancing, warns study as states reopen
As more states are springing back to life, a new study has made a dire prediction: without social distancing, the US could have seen a jump of 35 times more Covid-19 cases. The researchers also studied the effects of social distancing in the US between March 1 and April 27 and found that longer social distancing slowed the new coronavirus. "Both shelter-in-place orders (SIPOs) and closures of restaurants, bars, entertainment-related businesses substantially slowed the spread of Covid-19," the authors wrote in their study.
"Nonetheless, we provide important information about the benefits of social distancing for policymakers to consider as they decide on strategies for restarting economic activity," they added. Between March and April, state and local governments imposed social distancing measures. The measure meant that schools, entertainment venues, gyms, bars and restaurant dining areas had to shut their doors. Many states imposed SIPOs or stay-at-home orders covering more than three-fourths of Americans.
Some earlier studies have thrown lights on the topic. Evidence from the 1918 influenza pandemic indicates that social distancing measures will reduce the average contact rate by 38%. For the current pandemic, scientists from the Imperial College London modeled the impact of public health measures. They said that social distancing of the entire population, home isolation of infected individuals and household quarantine of their family members along with possible school and university closure could interrupt the spread and reduce case numbers to low levels. But the number of cases could pick up again.
Professor Steven Riley, Professor of Infectious Disease Dynamics within J-IDEA, said: "We have to accept that COVID-19 is a severe infection and it is currently able to spread in countries such as the US and the UK. In this report, we show that the most stringent traditional interventions are required in the short term to halt its spread. Once they are in place, it becomes a common priority for us all to find the best possible ways to improve on those interventions."
In this study, the team evaluated the effects of the government's message on infection rates. "At issue is not whether isolation works to limit the spread of disease, but rather whether the particular government restrictions designed to encourage social distancing in the US reduced spread relative to simply providing information and recommendations," the authors wrote in their study.
So they gathered data from 3,138 counties for over 58 days. Because the US did not detect new cases on most days in January and February, the team decided to study the effects from March. They ended the analysis after April 27 as states began reopening. If these measures stayed in place for 16-20 days, the daily growth rate reduced by 9%. The cases dropped by almost 8% and 7% after 11 to 15 days and after six to ten days, respectively. Finally, the cases dropped by nearly 6% after five to six days of social distancing. When the team removed all of the measures, the analysis showed that cases could jump by 35 times.