Thread by @AdamJKucharski

Any discussion of daily testing vs quarantine for contacts of cases in schools needs to address the key epidemiological question: if a child in a school tests positive, what do you do next? 1/

Encouraging ventilation etc. to reduce transmission risk is important, but you still have to decide what to do about a positive result. Do you quarantine their contacts or not? 2/

If you decide to abandon quarantine because you think ventilation etc. has sufficiently reduced risk, then this still means accepting higher transmission risk than if quarantine had remained in place. 3/

However, if you decide anything that results in more transmission risk than implementing full quarantine is unacceptable, then this means implicitly placing zero value on keeping children in school… 4/

Suppose, hypothetically, daily testing means 1% higher transmission risk but avoids quarantine keeping contacts out of school. Is this a ‘worse’ outcome than before? How about if transmission risk is 5% higher? Or more? 5/

If you decide 'less transmission is always optimal' is guiding principle, then should quarantine be extended to 14, or even 21 days, to ensure maximum transmission reduction? 6/

More broadly, should school-based measures be implemented in future for other respiratory infections (e.g. cidrap.umn.edu/news-perspecti…)? 7/

Ideally, we’d all like less COVID and less disruption. But the has pandemic forced decisions on what to prioritise, and what is an acceptable tradeoff, so need to consider available options carefully. And finally, a reminder:

https://twitter.com/AdamJKucharski/status/1360255631672893444?s=20

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