The past week has seen tensions rising about scientific modelling during the pandemic. Projections cited by UK and devolved governments as they tightened Covid restrictions have led to strained exchanges. But modelling is essential because it tell us:
What are the range of possible outcomes based on what we know?
Society can’t just wait for things to happen. We can and do save lives by being prepared for a range of things, only some of which happen. As information increases, the model improves, and the range of outcomes narrows as scenarios are eliminated.
What assumptions make the most difference to these outcomes?
Modelling told us that hospitalisations per 1,000 infections is important to outcomes, so its measurement was prioritised. Modelling can also show that by the time we know something, it is too late. Thus, it tells when decisions matter.
How do different interventions affect different scenarios?
In a world of limited resources, the government may have to choose one measure over another. But some things we can’t test, for example what happens when 10% of ambulance drivers are ill? (We won’t send home 10% one day just to document the consequences.)
The “what if” question. What if Omicron has a short generation time or co-exists with Delta?
Scientific models are not set in stone; they are open for inspection, updated with new information and, as errors are discovered, they are corrected. To date, the actual outcomes have been within the range of scenarios. For example, in the autumn, Scotland mandated mask-wearing with exceptions that some ignored, while England made masks voluntary but many wore masks anyway. What actually mattered to case numbers is what people did, not the legislation; no model can capture this perfectly.
Governments make the decisions about restrictions. I don’t envy them this burden during Covid but politicians and the public must hear the unvarnished truth about the range of health outcomes of Omicron; this means modelling. But it’s not the only input – economic, political and social considerations (outside science) need to be heard.
I do worry that media coverage of Covid has shifted from science journalists to higher profile political journalists. Not for nothing is the political slogan “if you are explaining you are losing” often employed. There is an important role for science-based policy advocates and scientists who explain the conflicting data to the public but avoid policy advocacy. I try hard to be the latter and admire the former; but I caution that it seems impossible to do both. If science becomes a tribal identity, then a chunk of fellow citizens will close their ears, to their and our detriment.
Professor Chris Whitty, England’s chief medical officer, is a model of compassion, honesty and humility that we should all aspire to, and some in the science community have fallen short of during Omicron.
Some usual suspects, mostly from politics, state they knew all along Omicron was less severe; they did not. There were signs that it could be milder right at the outset and I hoped it would be, but there were good reasons to suspect the opposite. False certainty does harm all round. Proper modelling must consider all plausible outcomes.
When the new data was published on Wednesday, the models changed. We are not out of the woods; should Omicron continue to spread rapidly, there are risks for the NHS and those developing long Covid.
Those arguing against further restrictions must be given airtime – some have interesting things to say. But those who smear modellers and scientists as “gloomsters” are dishonest and irresponsible. It’s a tactic of the political world, playing the man not the ball. Let’s talk about your models, tell us what you don’t know, what you assume and the risks you are prepared for the UK to run.
Just under 150,000 people have died from Covid in the UK. Every one of them meant something. To date, more people have died from Covid in the UK as a portion of the population than in most other advanced countries. We got things wrong. There will be a next time, and we must all do better if such tragedy is to serve a higher purpose. I would urge anyone who gets in front of a microphone or tweets or writes to think of the loss and show a little humility and humanity.
James H Naismith is director of the Rosalind Franklin Institute, Didcot, Oxfordshire