Lockdown restrictions in the UK are beginning to work, scientists said on Friday, as several studies showed coronavirus infections falling in England and most of the rest of the country.
The latest official estimate of R, the average number of people to whom someone infected passes the virus, is between 0.8 and 1.0 both for the UK and for England.
“The number of new infections is likely to be shrinking by between 1 per cent and 4 per cent every day,” said Sage, the government’s scientific advisory group for emergencies.
Last week Sage put R for the UK at 1.2 to 1.3.
More good news came from the latest Office for National Statistics infections survey. ONS estimated that during the week ending January 16, just over 1m people in England had Covid-19, equivalent to about 1 in 55 or 1.8 per cent of the population.
The last ONS survey released a fortnight ago had shown that 1 in 50 were infected during the week to January 2.
“In England, we have seen a slight decrease in the percentage of people testing positive,” said Sarah Crofts, senior statistician for the Covid-19 Infection Survey.
“The picture across the UK is mixed. In Scotland and Wales rates of infection have levelled off, but Northern Ireland has seen an increase in the percentage of people testing positive.”
A third source of reassuring data released on Friday was the Zoe Covid Study, which showed that Covid-19 cases in the UK had halved in two weeks.
Reports from people with the Zoe symptom-tracking app suggested that there are currently 34,100 new symptomatic cases of Covid-19 per day in the UK on average, against 53,528 new daily cases a week ago and 69,958 a fortnight ago.
The Zoe study showed R to be 0.8 across the UK as a whole, with new daily cases falling in every region.
Tim Spector, professor at King’s College London and lead scientist on the study, said: “If the trend continues we expect hospital admissions to fall next week and deaths to start plateauing and falling in the near future. Signs are hopeful we’re on our way out of this situation but risk of infection still remains high and we still have a way to go.”
There are variations around the country. Sage said infections were falling fastest in “areas that have been under tighter restrictions for longest, including Tier 4 over the festive period [the east of England, London and the south-east]”.
The latest data releases were a welcome contrast to another closely watched study, the React-1 survey led by Imperial College London, which reported on Thursday that there was no evidence of a decline in infections and, if anything, they were increasing.
React-1 analysed 142,900 nose and throat swabs from a representative sample of the English population between January 6 and 15. The Imperial researchers gave a central estimate of 1.04 for R, which would mean that Covid-19 prevalence was rising slowly from an already very high base.
But the authors at Imperial acknowledged that one limitation of their analysis was that no data was collected during December or the beginning of January — the period over which other sources estimate prevalence to have been highest — meaning trends had to be inferred from a very short time window, whereas other studies have collected data continuously over the winter.
Independent experts cautiously welcomed the results released on Friday. “Yes, the data do suggest that the current measures — while obviously very difficult for many — are beginning to control spread,” said Liam Smeeth, professor of clinical epidemiology at the London School of Hygiene & Tropical Medicine.
“If we all continue to follow the guidance, we can hope that over the coming weeks we will see continued falls, likely to be helped by the vaccination rollout.”
“It is essential that everyone continues to stay at home, whether they have had the vaccine or not,” the Sage committee said. “We all need to play our part, and if everyone continues to follow the rules, we can expect to drive down the R number across the country.”