The new coronavirus variant sweeping the UK could more easily infect children, scientists have suggested.

Experts say the data indicates it may be able to better spread among kids than other strains, but that analysis is still ongoing.

Previous studies have shown 1-5% of diagnosed Covid-19 cases occur in children. However, cases among kids are thought to be largely asymptomatic, meaning they don’t show symptoms. 

The new variant, dubbed VUI – 202012/01, which stands for the first Variant Under Investigation in December 2020, could mean more children are becoming infected than normal. But this is yet to be proven. 

Professor Neil Ferguson, a scientist on the government’s New and Emerging Respiratory Virus Threats Advisory Group (NERVTAG), said during the second lockdown in England, there was an age shift in the distribution of the virus.

Speaking at a Science Media Centre press briefing, Prof Ferguson, of Imperial College London, said: “There is a hint that it 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.”

He added: “What we’ve seen is, during the lockdown in England we saw a general distribution of the virus towards children, and that was true in the variant and the non-variant, and it is what we would expect, given that we had locked down which reduced adult contact but schools were still open.

“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.”

Prof Ferguson continued: “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.

“But a lot more work needs to be done to actually explore this in more detail.”

NERVTAG member Professor Wendy Barclay, head of the department of infectious disease at Imperial College London, urged caution about what is said regarding spread among children. “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 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.”

Matt Hancock, the health secretary, has said the new variant is unlikely to cause more serious disease than other variants.

Prof Ferguson said the latest estimates were that the new variant could be between 50% to 70% more transmissible and that NERVTAG now had “high confidence” there is a substantial increase in transmission. However, uncertainty around the figures meant it had not pinned a final number on it.

He also said the virus has spread to other parts of the country, with Susan Hopkins, of Public Health England (PHE) saying a hotspot in Cumbria was being investigated.

Asked whether the new variant may become the dominant one in the UK, Prof Ferguson said: “I think it’s highly likely to, from the trends we’ve seen so far, and how it’s spread in the areas which got infected first. Of course making predictions is a dangerous thing.”

Prof Ferguson said his best assessment is that the virus will decline over the next two weeks for both the variant and non-variant. “Contact rates tend to be lower over Christmas with the tightening of Christmas measures and tier 4 in place in the highest areas,” he said. “I would hope certainly to be seeing [the] 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.”