COVID infections in England had been falling since July. However the proportion of individuals testing constructive began to rise once more within the first few days of September.
At its July peak the Workplace for Nationwide Statistics (ONS) estimated that roughly 3.1 million individuals in England (1 in 17 individuals) examined constructive, however by the primary week in September this had fallen to 700,000. Through the week ending September 17 (the newest ONS knowledge now we have on the time of writing) virtually 900,000 individuals had been estimated to be contaminated in England.
There’s all the time a lag between new infections beginning to improve and this being mirrored within the figures, so the variety of new day by day circumstances may have begun to rise a few week earlier than the top of August. And the variety of individuals contaminated by now could be prone to be considerably higher than 900,000.
We are actually into the following large wave of COVID infections in England, and possibly elsewhere within the UK. The ZOE COVID research app broadly agrees with this timeline.
This wave of infections is completely different, nevertheless. Earlier main COVID waves within the UK have been pushed by the emergence of latest variants, equivalent to alpha, delta, and most just lately, a string of omicron subvariants.
There are two comparatively new variants underneath investigation within the UK, BA.2.75 and BA.4.6, however neither characterize quite a lot of per cent of infections. By far the commonest variant within the UK stays BA.5, which fuelled the wave of infections in June and July. So the present wave isn’t being pushed by a brand new variant.
What’s behind this new wave?
Faculties began again in the course of the first week in September, and whereas this will likely now be contributing to the brand new wave, infections began rising too early for faculties to be the first driver.
One chance might be individuals coming back from abroad holidays. A latest ONS evaluation discovered travelling overseas was one of many strongest danger elements for testing constructive.
However in all probability the primary driver behind this present wave is waning immunity. We all know that for many extremely transmissible endemic infections the incidence of an infection is basically pushed by the speed at which immunity is misplaced within the inhabitants.
We additionally know that safety towards an infection or reinfection following COVID vaccination or certainly an an infection could not final lengthy. Thankfully safety towards extreme illness is extra sturdy.
Hopefully the fourth dose will present considerably longer-lasting safety towards an infection, nevertheless it’s too early to know for positive.
Learn extra:
COVID: how ICUs in England had been stretched to deal with the pandemic
What subsequent?
Many respiratory infections equivalent to influenza, RSV (respiratory syncytial virus) and the opposite human coronaviruses trigger extra infections within the autumn and winter months.
Whereas we don’t absolutely perceive all the explanations for this, contributing elements could embrace falling temperatures, diminished daylight, and other people being indoors extra. It’s probably that these elements, together with waning immunity, will drive up new COVID infections for a number of weeks to return.
However for the way lengthy and the way excessive an infection charges will climb is tough to foretell with any accuracy. Previous modelled estimates of future an infection traits have typically been broad of the mark. Additionally, we don’t know whether or not a brand new variant would possibly seem within the coming weeks that might drive up infections even additional, significantly if it’s extra transmissible or higher at evading our immune defences.
Maybe of much more relevance than an infection charges is the probably affect infections may have on well being companies this autumn and winter. New admissions to hospital in England have been rising since early September.
Notably although, most new infections are actually reinfections. Virtually 90% of England’s inhabitants had already had at the least one an infection by August 2022. On common reinfections are much less prone to find yourself in hospital than first infections.
Throughout 2022 we’ve seen the variety of individuals in hospital due to COVID falling throughout every successive wave, and this pattern ought to proceed.
However in latest months the an infection charge in older individuals has been larger than in youthful individuals. This contrasts with a lot of the previous two years, the place infections have been decrease in individuals over 50.
As a result of fewer older individuals have had a primary an infection – and usually tend to be hospitalised for COVID within the first occasion – this might improve hospital admissions.
The autumn booster marketing campaign, which is providing fourth doses to individuals over 50, these with sure medical circumstances and well being and social care employees ought to go a protracted solution to decreasing this strain. However by September 28 solely about 15% of individuals over 50 in England had obtained an autumn booster.
Twin peaks
The opposite large concern is how badly influenza will come again this winter and whether or not a peak in flu infections will coincide with the height in COVID infections. If the UK has a very unhealthy flu season and the peaks coincide, then it may count on extreme pressures on well being companies resulting from each excessive numbers of admissions and employees illness.
Thus far influenza exercise in England stays low, however that might change very quickly. Australia has seen a excessive variety of flu infections this yr, although not not as many as some years previously decade.
The pandemic will not be but over and we’re prone to see excessive numbers of infections this winter. Whether or not an infection numbers exceed the peaks from earlier this yr, solely time will inform. In my opinion, it’s unlikely that we are going to see pressures on the well being service anyplace close to as nice as we noticed final winter, however that does rely partly on the effectiveness of the present vaccination marketing campaign. Please, if invited for an autumn booster, do take up the supply.
Paul Hunter consults for the World Well being Group. He receives funding from Nationwide Institute for Well being Analysis, the World Well being Group and the European Regional Growth Fund.