Lockdown in north of England a 'rash decision' not backed up by data, Oxford professor says

Imposing a widespread regional lockdown in the north west was a ‘rash’ decision which is not backed up by the data, an Oxford professor has claimed.

People in Greater Manchester, east Lancashire and parts of West Yorkshire were banned from meeting different households indoors, in a move that Matt Hancock, the health secretary said was ‘absolutely necessary.’

But Professor Carl Henegehan, director of the Centre for Evidence-Based Medicine at Oxford said the figures were skewed by delayed test results and when plotted by the date the test was taken showed no overall alarming rise.

“The northern lockdown was a rash decision,” he said. “Where’s the rise? By date of test through July there’s no change if you factor in all the increased testing that’s going on.

“As areas are tested, like Oldham, then there’s a slight rise in detected cases, asymptomatics.

“It’s not clear  if these are false positives, or if these folk have viable virus or just RNA  fragments detected by a test threshold that picks up minute traces of RNA.

“While you get these small clusters, which will have been occurring for some  time, they have not led to an overall increase in cases

“The government needs to allow the local public health teams to do their job when localised clusters emerge.”

Mapping the coronavirus trend by result date appears to show a slight increase in cases over the past few weeks, but based on specimen date - a more reliable measure - cases appear to have plateaued and may even be falling.

Between July 22 and July 29 the seven day rolling average of reported cases jumped between those two dates from 659 to 753 - 16.7 per cent.

However when judged by specimen date the seven day rolling average actually dropped from 641 to 442, a 31 per cent decrease.

Any rise is also being skewed by a general increase in testing. The seven-day rolling average for tests carried out between July 22 and July 29 jumped from 137,427 to 153,252 - an 11.5 per cent increase, wiping out much of the increase.

“Why is no one checking this out at government level?,” added Prof Heneghan

“The specimen date is more reliable as the reporting data will be skewed by the delay in pillar 2 testing reporting.”

At a press conference on Friday, shown above, Boris Johnson also said that the government had been swayed by Office for National Statistics data (ONS) which showed a ‘slight increase

The ONS estimated that 35,700 people in England were infected with Covid-19 between July 20 and July 26, or 1 in 1,500 people. The week before statisticians had calculated around 27,700 were infected, or about 1 in 2,000.

However the new calculation was based on just 59 people testing positive out of 116,026 swab tests (0.05 per cent). The previous week just 45 people tested positive out of 114,674. (0.39 per cent). It means that statisticians have extrapolated data for a whole country based on just 14 extra positive tests.

The ONS also admitted that it was unable to spot any concrete regional differences. In fact, its modelling showed the north west as having one of the lowest incidences of Covid-19, while suggesting cases were rising in the East Midlands and London.

Public Health England’s (PHE) own surveillance based on positive tests reported that cases in England increased from 4,062 to 4,130 in the week ending July 26 - a rise of just 1.6 per cent. According to ONS figures the rise was closer to 28 per cent.

PHE data also showed that cases were already falling when many areas were locked down, including Blackburn, Rochdale, Kirklees and Rossendale.

Professor Sheila Bird, Formerly Programme Leader, MRC Biostatistics Unit, University of Cambridge, said that while the ONS data was ‘alerting’ it may not result in more serious cases or admissions to hospital.

“Some of the newly swab-test positive infections in the ONS Infection Survey will never become symptomatic – and likewise a similar proportion of the 3200 new infections daily in the community in England.

“These asymptomatic infected persons are capable of transmitting the virus.

“We need to know more about the demography (age, sex, ethnicity) of the newly infected persons in the ONS Infection Survey as disease progression and hence hospital admission are less likely for younger infectees.”