Home   News   National   Article

‘Circuit break’ lockdown move could temporarily slow Covid-19 spread – experts

PA News

A temporary “circuit break” of national lockdown measures could slow the spread of Covid-19 while buying time for NHS Test and Trace to improve, an expert has suggested.

Mark Woolhouse, professor of infectious disease epidemiology at the University of Edinburgh, said an “optimistic” aim of new restrictions could be to drive down the coronavirus R number and reduce the incidence of new infections by as much as a half for a short period.

But he warned that the approach would only defer the challenges of the pandemic.

(PA Graphics)
(PA Graphics)

Other experts highlighted that further measures would only control rather than stop transmission of the virus, and questioned whether a proposed period of two weeks would be effective.

Their comments come amid reports that the Government is considering new national restrictions to curb the spread of Covid-19, with cases rising and winter approaching.

Analysing the concept of a “circuit breaker”, Prof Woolhouse said: “The aim is to use additional social distancing measures to reduce the R number well below one for a short period; two weeks has been suggested.

“That would drive down the incidence of new infections, perhaps by as much as half if R fell to a similar value as during lockdown, though that may be optimistic.

“Lower incidence means lower risk of infection and, for the minority most vulnerable to Covid-19, lower risk of severe illness, although the latter benefit might not be seen until after the circuit breaker was over.”

(PA Graphics)
(PA Graphics)

Data released by the Government Office for Science and the Scientific Advisory Group for Emergencies (Sage) shows the estimate for the R value – the reproduction number of coronavirus transmission – across the UK is between 1.1 and 1.4.

Prof Woolhouse said that after two weeks the rate of new cases would be expected to increase again, but take time to return to the level seen before measures were introduced.

He added: “Exactly how long would depend on the measures kept in place after the circuit breaker.

“The expectation is that all this will buy several weeks of time which could be used, for example, to improve the performance of the test, trace and isolate system. ”

An advantage of the circuit break approach is that it can be planned for, in contrast to earlier lockdowns, bringing less disruption to businesses and the economy, Prof Woolhouse said.

(PA Graphics)
(PA Graphics)

But he warned: “As with all lockdown-type interventions a circuit breaker only defers the problem. It does not guarantee that we wouldn’t need another one in the future, and so on.”

According to reports, potential new national measures could see restrictions placed on the hospitality sector, such as asking pubs and restaurants to limit their opening hours.

Similar measures have already been introduced under local lockdowns, for example in areas across the North East.

Jonathan Ball, professor of molecular virology at the University of Nottingham, said: “I haven’t seen the detailed scientific advice, but it sounds like the plan would be to control, rather than stop transmission and new cases by focusing on restricting or curtailing those activities where the evidence points to increased risk – bars and restaurants, for example.”

Prof Ball added: “It does seem ironic that after encouraging mass attendance at pubs, cafes and restaurants through Eat Out to Help Out, that we are now contemplating restricting or closing those activities down.”

Rowland Kao, professor of veterinary epidemiology and data science at the University of Edinburgh, questioned the effectiveness of the short term imposition of extra restrictions.

(PA Graphics)
(PA Graphics)

He said: “While a two-week lockdown will undoubtedly reduce the infection rate, the danger is that it is uncertain whether something less than the total lockdown of March will have enough of an impact to actually reduce R below one under the current circumstances – eg, if schools and universities are allowed to continue to operate with in-person contact.

“If it does not, the pressures on Test and Trace and the risks to the vulnerable, including those in hospitals, will only continue to increase.

“Crucially, two weeks will be insufficient time to fully assess the impact of those restrictions. Even if R drops below one, cases will continue at similar levels for some time.

“Thus, for the slowing down effect of the ‘circuit break’ to be helpful, this would require that there be enough time for the current Test and Trace difficulties to be resolved. Two weeks is unlikely to be enough for this.”


Close This site uses cookies. By continuing to browse the site you are agreeing to our use of cookies.Learn More