Covid: How many cases might contact tracers have missed?

A BBC analysis suggests this could mean at least 34,000 contacts were left in the dark about having been exposed to the virus. A BBC analysis suggests this could mean at least 34,000 contacts were left in the dark about having been exposed to the virus.

And those missed contacts, who tracers are now urgently trying to reach, may have been unknowingly spreading the virus on to others for days.

Speed is of the essence when it comes to contact-tracing. Every missed day represents an opportunity for the infection to travel.

At the moment, about 60% of people who are reached by a contact tracer will provide contacts - and they hand over the names of five people on average.

Of those contacts, 72% are reached and told to self-isolate.

Applying that performance to the 15,841 cases missed due to the IT glitch, we can estimate that almost

would have provided just under

contacts, of whom about

would be reached.

That's a conservative estimate, since the original 15,841 cases could have had as many as 80,000 close contacts, although the test-and-trace system would have been unlikely to reach all of them.

Based on NHS Test and Trace findings so far, most of the contacts would be what experts call "non-complex" cases - people living in the community rather than in care homes, for example.

Around 60% would be people living in the same household as the infected person who tested positive.

So, a big chunk of them may already be aware of the positive result.

Health Secretary Matt Hancock told Parliament 51% of the missed cases had been contacted since the weekend.

Read the full story at https://www.bbc.co.uk/news/health-54418603

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