Study in The Lancet Public Health finds physical distancing can reduce cases in Wuhan by 92% in the short term and 24% in longer term
Even as India embarks on a long 21-week exercise in social distancing, a study from Wuhan found that cases in the epicentre of the novel coronavirus has found that cases there could reduce by as much as 92% because of the lockdown there. In his address to the nation on Tuesday evening, prime minister Narendra Modi announced a nationwide lockdown.
“Our projections show that physical distancing measures were most effective if the staggered return to work was at the beginning of April; this reduced the median number of infections by more than 92% and 24% in mid-2020 and end-2020, respectively. There are benefits to sustaining these measures until April in terms of delaying and reducing the height of the peak, median epidemic size at end-2020, and affording health-care systems more time to expand and respond. However, the modelled effects of physical distancing measures vary by the duration of infectiousness and the role school children have in the epidemic,” the researchers led by those from the London School of Hygiene & Tropical Medicine, concluded.
In Wuhan, physical distancing measures reduced the median number of infections by more than 92% and 24% in mid-2020 and end-2020
However, the findings may not be applicable in the same way in every country, the researchers warn.
“Our results won’t look exactly the same in another country, because the population structure and the way people mix will be different. But we think one thing probably applies everywhere: physical distancing measures are very useful, and we need to carefully adjust their lifting to avoid subsequent waves of infection when workers and school children return to their normal routine. If those waves come too quickly, that could overwhelm health systems”, said Dr Yang Liu from London School of Hygiene & Tropical Medicine.
Writing in a linked Comment, Dr Tim Colbourn from University College London, UK (who was not involved in the study) says: “The study by Kiesha Prem and colleagues in The Lancet Public Health is crucial for policy makers everywhere, as it indicates the effects of extending or relaxing physical distancing control measures on the coronavirus disease 2019 (COVID-19) outbreak in Wuhan, China.”
He continues: “Given many countries with mounting epidemics now potentially face the first phase of lockdown, safe ways out of the situation must be identified… New COVID-19 country-specific models should incorporate testing, contract tracing, and localised quarantine of suspected cases as the main alternative intervention strategy to distancing lockdown measures, either at the start of the epidemic, if it is very small, or after the relaxation of lockdown conditions, if lockdown had to be imposed, to prevent health-care system overload in an already mounting epidemic.”