Why social distancing is still the most effective non-pharmaceutical intervention for COVID-19

From the moment COVID-19 started to spread to almost all parts of the world, social distancing became one of the most popular recommendations, apart from hand washing and wearing face covers. The very idea of social distancing — renamed physical distancing by the World Health Organization (WHO) in April 2020 — gained immense traction, especially with governments across the world implementing lockdowns to enforce it. [caption id=“attachment_8283741” align=“alignleft” width=“380”]  Representational image. Image by Tumisu from Pixabay.[/caption] So, it would be wrong to assume that the importance of social distancing was ever doubtful. However, with lockdowns being lifted gradually all over the world, it’s likely that people might mistakenly assume that social or physical distancing is no longer needed. Three new studies conducted by different research groups across the world indicate that physical distancing is still the most effective type of non-pharmaceutical intervention (NPI), especially in the absence of pharmaceutical ones in the form of drugs or a vaccine. Here’s what these new studies reveal:

Social distancing cut COVID-19 transmission by half in the US

Researchers from Johns Hopkins University studied the rate of transmission of COVID-19 across 1,417 counties of the USA from 15 March to 28 May, and concluded that 82% of these counties have been able to “reduce the reproductive rate of novel coronavirus to below 1.0 via the implementation of NPIs.” This means, thanks to NPIs like stay-at-home orders, lockdowns, etc, an infected person is now able to spread the SARS-CoV-2 virus to just one or less person in 82% of these counties. The study also found that people in urban areas responded better to stay-at-home orders issued by local governments, while those in rural areas adhered to less restrictive orders issued by the US federal government. This study still insists that herd immunity is a far cry for the US, but the implementation of measures like social distancing should be continued even as the nation rolls back on lockdowns. A pre-print version of the study is available on medRxiv.

Delay in social distancing leads to longer outbreaks

Epidemiological researchers at the University of Texas, Austin, analysed COVID-19 outbreaks in 58 cities of China and found that a delay of even one day in the implementation of social distancing norms added 2.4 days to the length of the outbreak. The study, which is set to be published in the journal Emerging Infectious Diseases, reveals that the importance of strict and immediate implementation of social distancing does not diminish after the duration of the first outbreak is over. These measures can also benefit countries that witness a resurgence of COVID-19 in the coming months. So, while this study was unable to pinpoint which exact social distancing measures were most effective, it underlined the fact that the timing of the first social distancing orders had a huge impact on compliance throughout the outbreak.

Physical distancing, masks are most effective in reducing risks

The study published in The Lancet yesterday reveals that maintaining a physical distance of at least one metre in both healthcare and community settings can reduce the risks of contracting COVID-19 by 82%. The study also found that every additional one-metre distance to the original more than doubled the protection. The researchers studied transmission up to a distance of three metres and confirmed these findings. The same study also revealed that masks (multilayer ones) and respirators can additionally reduce the risk of infection by 85%, especially in healthcare settings. This study was based on the systematic review and meta-analysis of 172 observational studies and 44 comparative studies on SARS, MERS, COVID-19 and other betacoronaviruses. For more information, read our article on Can physical distancing still work in India? Health articles in Firstpost are written by myUpchar.com, India’s first and biggest resource for verified medical information. At myUpchar, researchers and journalists work with doctors to bring you information on all things health.