Intended for healthcare professionals

Rapid response to:

Feature Briefing

Covid-19: the problems with case counting

BMJ 2020; 370 doi: https://doi.org/10.1136/bmj.m3374 (Published 03 September 2020) Cite this as: BMJ 2020;370:m3374

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Rapid Response:

Re: Surveillance Bias and Overdiagnosis of Covid-19

Dear Editor

Arnaud Chiolero writes:

"Overdiagnosis of Covid-19 does however not imply overdetection of SARS-CoV-2. On the contrary. Detection of all infections and tracing of close contacts is key to stop spread and contain outbreaks.. In that sense, there is no overdetection because it is useful, at a population level, to detect all persons with the virus."

While he is mindful of the risk of over-diagnosing COVID-19 it is till questionable how useful the tracking of infection is if this is used by our government to alarm people (who might not be so pre-armed about subtlties of definition) and it generates lots of false positives i.e. if we do not test at least we will at least not get false results, or results which are impossible to interpret. The speculative routine screening of healthy citizens for viruses they might be carrying is a dystopian nightmare which would of course prevent life ever returning to normal - as if the social cost of the present misadventure was not bad enough.

Arnaud Chiolero, 'Surveillance Bias and Overdiagnosis of Covid-19', 6 September 2020, https://www.bmj.com/content/370/bmj.m3374/rr-1

Competing interests: AgeofAutism.com, an on-line daily journal, concerns itself with the potential environmental sources for the proliferation of autism, neurological impairment, immune dysfunction and chronic disease. I receive no payment as UK Editor

07 September 2020
John Stone
UK Editor
AgeofAutism.com
London N22