Trace and isolate is “the most important requirement right now in every country” to tackle COVID-19, warned David Nabarro, coronavirus special envoy to the World Health Organization.
Nabarro added that ideally testing was needed as well, but if this was not available he said governments could use symptoms instead of testing, which was “better than nothing”.
Asked about lifting lockdown measures such as some children returning to school on 1 June, he told BBC Radio 4’s Today programme (15 May 2020): “Other countries are saying very clearly, we want to make sure that the capacity to test, trace and isolate is present throughout our country before we really start lifting the restrictions on movement.
“After all, what is a lockdown? It's freezing the virus in place and it's giving us a time to get ready so that when we release the lockdown, we're better protected.
“And I suppose my request to all countries is that rather than giving precise dates, they say we'll release the lockdowns when we know that we've got the defense mechanisms in place, where we know that our people understand the severity of this virus and what we've got to do, it got to do.
“And when we've made sure that in the settings where the virus is most easily transmitted, we put in place the best possible protection to keep those at risk most safe.”
He added: “I would really hope that individuals everywhere concentrate on the fact that this virus is extraordinarily dangerous and that it can develop explosive outbreaks very rapidly that overwhelm health services and kill people.
“What we have to focus on is the defenses that we put in place right across our societies to keep the R number low, even though we're getting on with our social and economic activities. And that's the test, trace and isolate strategy that's been shown in other countries to be the key to living with this virus as a constant threat and getting on with life.”
Nabarro warned not of a second wave, but of a “constant threat” and that proper systems needed to be in place to reduce the likelihood of “explosive outbreaks” over the summer and into the autumn.
He added: “Movements are restricted through physical distancing and lockdowns, you expect the R number to drop, but that doesn't mean that the behaviour of the virus has suddenly changed.
“All it means is that we've made it harder to propagate. And so as soon as movement restarts, then the R number will climb again. And that means that we actually prefer to concentrate on what societies are doing to prevent that virus from being transmitted rather than the actual R number itself.”
On new evidence that certain groups are more at risk from the virus than others – people from BAME backgrounds and those with diabetes for example – he said he was not in favour of mass shielding. He said the right information and “encouragement” needed to be given to these groups so they could physical distance, and reduce their exposure to the virus.
Nabarro said that we needed to take seriously that in certain occupations people needed to be closer together and that the structure of those professions needed to be changed.