Coronavirus infection rates remain high but are showing clear signs of declining in most areas of the UK, new data suggests.
The latest data from the Office for National Statistics (ONS) suggests around 1 in 65 people in the community in England are estimated to have had the disease in the week ending 30 January, compared with 1 in 70 in Wales, 1 in 65 in Northern Ireland and 1 in 115 in Scotland. The week before the figures were 1 in 55, 1 in 70, 1 in 50 and 1 in 110 respectively.
“Our modelling suggests that the percentage of people testing positive in England decreased in the week ending 30 January 2021 but remains high,” the team report, adding declines were seen both in the percentage of cases which are thought to be down to the new variant of the coronavirus, B117, and those which are not.
Once again, the situation is not uniform across England, with the latest data suggesting that while the percentage of people testing positive for Covid overall has fallen in London, the south-east, north-west, north-east and the south-west, it has risen in the east of England and levelled off elsewhere.
However the team caution that there is a higher degree of uncertainty when it comes to regional data than national.
The data comes as the latest R figure for the UK – reflecting the average number of people an infected person passes the virus to – was revealed to be between 0.7 and 1 for the UK and between 0.7 and 0.9 for England. If R is above 1 the epidemic is growing; below 1 it is shrinking.
The ONS data suggests lockdown is having an effect, with the percentage of people testing positive for Covid falling in three of the four nations.
But the drop is not as dramatic as might be expected from the fall in cases reported from the pillar 1 and II testing programme, or the positivity rate calculated by Public Health England from pillar II (community) tests.
Among the factors that might contribute to the disparity is that the datasets refer to different metrics. The daily case data is largely based on positive tests among people with symptoms who have recently come forward for a test, while the ONS survey is based on testing of randomly selected households. The latter picks up both symptomatic and asymptomatic infections but these could have begun up to a few weeks before the test was conducted.
Experts have previously suggested others factors might include changes in testing behaviour, or the growing use of lateral flow tests – which are less accurate – in pillar II testing.
Steven Riley, professor of infectious disease dynamics at Imperial College London and a member of the government’s Scientific Pandemic Influenza Group on Modelling (SPI-M) said the new ONS data chimes with the latest React-1 results – another population surveillance study in England.
“It’s good news that the overall trend is down, but it’s not clearly down in some of the regions,” he said, adding there remain important differences between cases and infections . “We think infections are the most reliable indicator of future hospitalisations and deaths.”