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The Office for National Statistics (ONS) have released the latest data from their COVID-19 Infection Survey.
Dr Simon Clarke, Associate Professor in Cellular Microbiology, University of Reading, said:
“The latest Office for National Statistics data reports a deteriorating situation in terms of infection numbers in the UK. The current position can also be compared with the same week last year, just before a new national lockdown began in November. While in autumn 2021 we now have a largely vaccinated population, the figures show that this does not prevent risk to vulnerable individuals, to the NHS, or to the economy and wider society.
“Compared to the same date in 2020, the situation in England is significantly worse in terms of numbers of infected people. One year ago, when we were on the verge of the November lockdown, one in 100 people was infected. This year, the rate is double that, with one in 50 infected.
“This is the result of England’s policy to “run hot” by lifting restrictions while also experiencing high case numbers. While numbers of infections are double the figures a year ago, it is also true that the number of deaths and hospitalisations remains lower that it was during the same period.
“The high case numbers are having an impact on deaths and NHS workloads, however. The number of Covid-19 patients in English intensive care beds is almost exactly the same as it was a year ago. Yesterday’s government figures indicate that there were 794 patients in ICU, whereas there were 788 on the same date last year.
“England’s policy of leaning heavily on vaccines, and peoples’ willingness to be careful in social situations, has decreased the numbers of people dying from Covid-19, but the virus is still able to find substantial numbers of those who are susceptible to it and render them seriously ill. It should be remembered that ‘squashing the sombrero’ or ‘flattening the curve’ was about reducing the shock to our healthcare system and spreading that load over a longer time period.
“If the situation were to deteriorate further, we risk creating pressure in the healthcare system leading to reduced access to care for the most unwell. If the situation deteriorates, anyone having a crash on the motorway or whose routine operation has taken a turn for the worse could find themselves without access to ICU at their local hospital.”
Prof Kevin McConway, Emeritus Professor of Applied Statistics, The Open University, said:
“More unwelcome news from the ONS Covid-19 Infection Survey (CIS). The latest weekly bulletin takes the estimates of the proportion of the community population that would test positive for the virus that can cause Covid-19 up to the week ending 22 October (or the week ending 23 October in Scotland). ONS estimate that those positivity rates increased in England and in Northern Ireland in the most recent week. In Wales and in Scotland ONS are more guarded in their assessments. For Wales they say that the numbers who would test positive increased in the latest two weeks, but that the trend was ‘uncertain’ in the most recent week. In Scotland ONS say that there were ‘early signs’ of an increase in the numbers who would test positive in the most recent week. ONS’s estimates of short-term trends from the CIS are inevitably less certain, statistically, in the smaller UK countries than they are in England, simply because fewer people are swabbed for the survey in the other countries than they are in England, and that’s doubtless part of the reason for their caution about the trends in Wales and Scotland.
“The upshot of all this is that the total of the ONS official reported estimates of the numbers who would test positive across the whole UK was about 1.28 million. That’s an increase of about 14% on the previous week’s total, so a pretty substantial increase in a week. In England, ONS are now estimating that about 1 in every 50 people in the community population (aged 2 and over) would have tested positive for the virus, if they were tested in the week ending 22 October. The previous week’s estimate was 1 in 55 – it doesn’t sound like a big increase, but in numbers of people, the estimated number who would test positive across England went up by 125,000 in a week. The latest weekly estimated rate of testing positive in England is higher than it has been since the CIS started in April last year, apart from just two weeks at the turn of the year (from 27 December to 9 January) when it was just a little higher, but still amounted to roughly 1 in 50 people testing positive. Of course, a rate this high doesn’t have anything like the same consequences in terms of hospitalisations and deaths as it did at the turn of the year, before vaccination had had a major impact, but it’s still a very high rate, historically, and that isn’t good.
“In Wales, the estimate of the proportion testing positive has been increasing pretty steadily since May. So again, for the most recent week, the ONS estimate is once more the highest it’s been since the survey started in Wales in July last year. The latest estimate is that about 1 in 40 people in Wales would have tested positive in the most recent week. Even allowing for the statistical margin of error, that’s very likely a higher infection rate than in England and considerably higher than in Northern Ireland or Scotland.
“The increases in the rate of testing positive in Northern Ireland and in Scotland are perhaps particularly unwelcome, because the rates there had generally been decreasing for several weeks. Of course, we’ll have to see whether these short-term increases continue over a longer period, and I certainly hope that they won’t. In any case, ONS estimate the proportion who would have tested positive in the most recent week in each of those countries as about 1 in 75, definitely lower than in England or Wales.
“For England, as usual, ONS provide quite a lot of detailed figures on the rate of testing positive in individual regions and in specific age groups. They can produce more precise estimates for groups like that than would be possible in the other three UK countries, because so many more people are swabbed for the CIS in England than elsewhere – but there is considerably more statistical uncertainty about the estimates for English regions and age groups than for the whole country, because of the smaller numbers in each region or age group. So, as always, it’s important not to be too definite about short-term trends.
“That said, the picture on age groups in England does look fairly similar to recent weeks. Depressingly, ONS estimate that the percentage of people who would test positive was increasing in five of the seven age groups that they look at. In the other two, school year 12 (so age 16-17) to age 24, and ages 25-34, ONS consider that the trend in the most recent week (ending 22 October) was uncertain. If anything, though, positivity might well be decreasing a little in those two groups, and certainly they ended up with two of the three lowest rates of positivity across the age groups, 1 in 100 for school year 12 to age 24, and 1 in 140 for ages 25-34. (The other age group with one of the three lowest estimated rates is those aged 70 and over, with an estimate of 1 in 120. That is therefore slightly higher than the rate for ages 25-34, but the margins of error for all these individual age groups are quite wide.) The ONS survey can’t tell us why infection rates are so low, relatively, in those late teenage and young adult age groups, but it’s likely to do with increases in relative immunity because of vaccination.
“Again the highest estimated positivity rates across age groups are for children, particularly those of secondary school age (school years 7 to 11) where ONS estimate that about 1 in 10 would test positive. That amounts to over a quarter of all the people who would test positive, of all ages, in England, even though only about 1 in every 15 people in the population is of secondary school age. It’s true that children of that age are very unlikely to become seriously ill from an infection, but they do have a risk of long Covid, and they can pass infections on to older people who are at higher risk of bad consequences (even, to some extent, if they have been vaccinated). In younger children (and 2 to school year 6) the positivity rate is lower than in children of secondary school age, but it’s still higher than all the other age groups, at about 1 in 25. Altogether more than half of all the people who would test positive for the virus in England are aged from 2 years up to school year 11 – that’s a risk both to the children themselves and to others. Increased vaccination of 12 to 15 year olds should help, though, and maybe in ONS releases for the next week or two we might see a positive effect of the half term break.
“In the English regions, ONS estimate that the rate of testing positive increased in the most recent week in six of the nine regions (the East Midlands, the West Midlands, the East of England, London, the South East and the South West). In the North West, though the trend was generally upward over the most recent two weeks, ONS consider it was uncertain during the latest week. ONS regard the trend in the remaining two regions (the North East and Yorkshire and the Humber) as uncertain in the most recent week. So the bad news here is that ONS do not consider the trend in positivity to be downwards in any of the English regions – though again there’s quite a lot of statistical uncertainty, and ONS rightly warn against over-interpreting small changes in trends. For the most recent week, ONS’s estimate of the proportion who would test positive is highest in the South West, at about 1 in 40. For all the other regions except London, the estimates are between 1 in 45 and 1 in 55. London again has the lowest estimated positivity rate, about 1 in 60, despite the probable increase in positivity since the week before (when the estimate for London was about 1 in 70). However, the statistical margin of error for London does overlap with the margins of error for several other regions, so we can’t be completely certain that the position in London really is more favourable than elsewhere.”
Prof Paul Hunter, Professor in Medicine, UEA, said:
“I would just point out that infection prevalence has increased in the last week of data compared to the previous week, but this reports covers the period 16th to 23rd October so this data is too soon to show whether the fall in daily reported cases in the past few days represent a real decline in infections. If infections really are falling in line with the daily reports on the DHSC Dashboard then the earliest we would see any impact in the ONS dataset is next Friday.”
Prof Jim Naismith, Director of the Rosalind Franklin Institute, and Professor of Structural Biology, University of Oxford, said:
“The ONS data are very valuable, they are the best measure we have of the infection. Up to the 22nd October, prevalence has increased in England to around 1 in 50 people, from 1 in 55.
“Based on the experience in Scotland which hit 1 in 45 some weeks ago before falling, I would expect the prevalence in England to have peaked or to be close to the peak.
“I would note that London has a lower prevalence, an increase to the national average has the potential to lift case numbers.
“If England has peaked, then other numbers will start to fall. I certainly hope so, 1000 people every day are ending up in hospital and 1000 a week dying. We are running very “hot”.
“If Scotland has indeed mapped out the path that England will follow, there is some less good news in this release. After some weeks of decreasing prevalence, prevalence in Scotland has levelled off and may have slightly increased to 1 in 75. This bears close watching, if sustained it suggests we may have another peak ahead.
“Analysis of prevalence over the last few weeks does suggest that the difference between Scotland and England in masking policy has in practice had little actual effect on case numbers.
“We know Delta spreads very rapidly and EU data suggest high vaccine coverage, universal masking and fairly stringent social restrictions are effective.
“The UK has through its politicians decided to live with high numbers of infections rather than impose meaningful restrictions.
“The booster campaign I am confident will save many lives in the most vulnerable populations. Thankfully prevalence is low in these age groups, likely due to the vaccine campaign.
“The prevalence in teens is over 9% and still appears to be rising. The roll out of vaccine to teens will coupled to the immunity from this high level infection in this population will drive down case numbers quite quickly.
“The decision to allow the virus to run through this age group (teens) will be an important subject for a cost benefit analysis over the next few years. The UK has trodden a distinctive path here.”
All our previous output on this subject can be seen at this weblink:
www.sciencemediacentre.org/tag/covid-19
Declared interests
Prof Kevin McConway: “I am a Trustee of the SMC and a member of its Advisory Committee. I am also a member of the Public Data Advisory Group, which provides expert advice to the Cabinet Office on aspects of public understanding of data during the pandemic. My quote above is in my capacity as an independent professional statistician.”
None others received.