The fundamental flaws of NHS Test and Trace

The NHS Test, Trace and Isolate programme — which was meant to be one of our main weapons in the fight against a second Covid-19 peak — has not had a good few weeks. First, when schools went back last month, an inevitable rush for tests was not met with sufficient supply. It then emerged that 16,000 people who had tested positive had failed to be transferred to the tracing system. Not a great start.

Then, the government’s Scientific Advisory Group for Emergencies (Sage), for long an advocate, quietly disowned the programme, saying it is having marginal impact. Are these just teething problems as the programme gets scaled up? I’m afraid that even if there are no more glitches or shortages of tests, three fundamental strategic flaws mean it will not suppress a second wave of Covid-19.

Let’s look at the latest data available from the first week of October. There were almost 200,000 new infections in England according to the Office for National Statistics. This is a 15-fold increase since mid-August. NHS Test and Trace located around 40 per cent of those infected: an improvement from late July when less than 20 per cent were found. This improvement comes partially from the doubling of testing, but also some targeted testing around university and other local outbreaks.

The bad news is that around 60 per cent are still not found, so their close contacts are not traced and isolated. This majority missed by testing is somewhat inevitable given the first strategic flaw in the approach: we rely on infected people to get a test. But ONS research suggests that two-thirds of people infected with Covid-19 are asymptomatic — and so don’t feel ill enough to get a test. In these circumstances, NHS Test and Trace did well to get even 40 per cent.