Strict social distancing greatly lowers chance of COVID-19 infection, study finds
Researchers from the Johns Hopkins Bloomberg School of Public Health (JHSPH) in Maryland, US, found that those who regularly dismiss outdoor social distancing were more than four times as likely to test positive for SARS-CoV-2 (COVID-19) infection, while those who reported practicing strict social distancing were just a tenth as likely to test positive for the virus.
In a large-scale evaluation of more than 1,000 people over a few weeks in late June, JHSPH researchers asked about participants’ recent travel outside the home, their use of masks, social distancing and related practices, SARS-CoV-2 infection history, and other COVID-19-relevant behaviours.
Participants included in the study were all living in Maryland, which has logged more than 113,000 confirmed cases of SARS-CoV-2 since the pandemic took hold in the US, as well as nearly 3,700 confirmed deaths, according to the Maryland Department of Health.
The researchers found that spending more time in public places was associated with a higher chance of SARS-CoV-2 infection; for example, the SARS-CoV-2 infection history was about 4.3 times more common among participants who stated that they had used public transportation more than three times in the prior two weeks, compared to participants who stated they had never used public transportation in the two-week period.
The infection history also was 16 times more common among those who reported having visited a place of worship three or more times in the prior two weeks, compared to those who reported visiting no place of worship during the period.
In contrast, those who reported practicing social distancing outdoors “always” were only 10% as likely to have a SARS-CoV-2 history, compared to those who reported “never” practicing social distancing.
In addition, the findings indicated a greater adoption of social distancing practices among some groups who are especially vulnerable to serious COVID-19 illness, suggesting that they were relatively aware of their vulnerability. For example, 81% of over-65 participants reported always practicing social distancing at outdoor activities, while only 58% of 18-24 year olds did so.
“The study showed that younger people in Maryland were less likely to reduce their infection risk with social distancing – and a month later a large proportion of the SARS-CoV-2 infections detected in the state was among younger people,” said Associate professor of medicine at Johns Hopkins School Medicine, Dr. Sunil Solomon.
“Our findings support the idea that if you’re going out, you should practice social distancing to the extent possible because it does seem strongly associated with a lower chance of getting infected,” said Solomon.
The novel coronavirus, SARS-CoV-2, has infected nearly 27 million people around the world, of whom some 900,000 have died, according to the World Health Organization (WHO). In the absence of a vaccine, WHO and other public health authorities have emphasised practices such as staying and keeping good hygiene while at home, and wearing masks and maintaining social distancing while in public.
