Scientists are investigating a shift in the distribution of COVID-19, with a “significant portion” of cases involving under-15s in recent weeks.
Although not giving precise figures, representatives from NervTag (New and Emerging Respiratory Virus Threats Advisory Group) said the change had become more evident over the past five to six weeks, during England's national lockdown.
A coronavirus report published by the Office of National Statistics (ONS) on 18 December noted that: "The percentage of people testing positive continues to be highest among secondary school-aged children."
The ONS's November Schools Infection Survey of 105 schools saw 1.5 per cent of secondary level students testing positive for the virus, compared to 0.9 per cent of primary school pupils.
More data is expected to be revealed next week.
Experts have speculated this shift may indicate the new variant of the coronavirus spreads more easily between children. However, there is no evidence that the current coronavirus vaccines – including the Pfizer vaccine – will not work on the new strain.
“There is a hint that [the new strain] has a higher propensity to infect children that may perhaps explain some of the differences, but we haven’t established any sort of causality on that but we can see that in the data,” said NervTag’s Professor Neil Ferguson at the press briefing.
“But what we’ve seen over the course of a five or six-week period is consistently the proportion of pillar two cases for the variant in under-15s was statistically significantly higher than the non-variant virus.
“We are still investigating the significance of that.”
He added: “This is a hypothesis at the moment – it’s not been proven.
“But if it were true, then this might explain a significant proportion, maybe even the majority, of the transmission increase seen.
“A lot more work needs to be done to actually explore this in more detail.”
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Professor Wendy Barclay, another NervTag member, clarified that the virus variant isn’t specifically targeting under-15s.
“We are not saying that this is a virus which specifically attacks children,” she said.
“We know that SARS-CoV-2, as it emerged as a virus, was not as efficient in infecting children as it was adults, and there are many hypotheses about that.
“And again, if the [new] virus is having an easier time of finding an entrance cell then that would put children on a more level playing field.”
She added: “Therefore children are equally susceptible perhaps to this virus as adults, and therefore given their mixing patterns, you would expect to see more children being infected.
“It’s not just the viruses specifically targeting them, but it’s just that it’s now less inhibited, if you like, to get into the children.”
NervTag estimates that the virus variant could be between 50 per cent to 70 per cent more transmissible than the old strain.
However, although scientists such as Prof Ferguson estimate the new strain of coronavirus will become the dominant form throughout the UK, some estimate that cases could decline over the next two weeks.
“Contact rates tend to be lower over Christmas with the tightening of Christmas measures and Tier 4 for in place in the highest areas,” said Ferguson.
“I would hope certainly to be seeing virus decrease.
“If we do that will give us some sense of the level of controls which need to be in place, the real question then is, how much are we able to relax measures in the new year, and still retain control.”
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