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An open letter published in the BMJ to the Secretary of State for Education, Gavin Williamson, suggests daily contact testing trials in schools are unethical and extending them to include the Delta variant puts everyone at risk.
Dr Alexander Edwards, Associate Professor in Biomedical Technology, Reading School of Pharmacy, University of Reading, said:
“This letter highlights a real challenge we are facing with the use of rapid COVID-19 tests. For a long time, the diagnostic testing community has known that real-world trials are important to understand if a new innovative test is really useful. Modern medicine is built upon evidence. Yet trials of diagnostics are also surprisingly difficult to conduct. We have been refining vaccine clinical trials for decades, and that experience allowed extremely fast and effective vaccine clinical trials to deliver powerful evidence to use them. Unfortunately, we have been less successful in trialling new diagnostic tests.
“Why is this trial so hard? Many people would argue that any contact of a confirmed COVID-19 case should self-isolate, but this causes particular disruption in schools. You can see the attraction of trying to develop ways to minimise this disruption. In the UK, contact tracing and self-isolation of contacts has been of variable effectiveness. In many parts of the world, a far stricter approach aims to eliminate any risk of onward transmission, at the cost of many more restrictions, for every case identified. A second problem is that normally, diagnostic tests are performed on people with symptoms, to help diagnose an illness. Asymptomatic screening falls outside this situation, and past experience teaches that screening programs are harder to develop than diagnostic tests. There is plenty of modelling used to simulate different testing and isolating methods, but unfortunately individuals vary a great deal, so the models have to cope with significant uncertainty. The delta variant may change critical numbers.
“This particular trial thus targets a particularly tricky problem with multiple challenges: in a difficult and contentious area (schoolchildren) with a challenging task (building an evidence base for screening) and using tests originally developed to aid a diagnostic decision, but repurposed for screening. It’s not surprising that there is debate, which should be encouraged to maximise our chance of arriving at the best conclusion, and we must invest more in future into getting better at the vital process of diagnostic test innovation.”
The open letter ‘Daily contact testing trials in schools are unethical and extending them to include the delta variant puts everyone at risk’ was published in the BMJ on Thursday 17 June 2021.
All our previous output on this subject can be seen at this weblink:
www.sciencemediacentre.org/tag/covid-19
Declared interests
Dr Alexander Edwards: “No conflicts. I am involved in a UKRI funded project focussed on design of community COVID-19 tests. No connection with the letter or with the trial in question.”