The festive season may bring back memories of Christmas COVID waves gone by.

While restrictions were in place in 2020 and 2021, many were forced to spend Christmas Day alone or isolated from loved ones.

In the latter part of this year, virus levels decreased month-on-month, but positivity rates have crept up again with increased social mixing in the run-up to 25 December.

And a sub-lineage of the so-called “Pirola” variant – JN.1 – has been spreading, with the UK Health Security Agency sub-categorising it on 4 December due to its spike protein mutation and “increasing prevalence within the UK and international data”.

In the absence of restrictions, with COVID circulating again, Sky News looks at current virus levels and what the guidance is for those who catch it over the Christmas break.

COVID rates rising

The latest data, which covers the week ending 9 December, shows COVID cases increasing by 39% on the previous week.

COVID positivity rates increased to 7.5% in England for the week ending 14 December, from 6.4% the previous week. Flu positivity also increased significantly from 2.4% to 5.6% that week.

The reversal of previously low virus trends is the inevitable result of more indoor gatherings during the festive period, scientists tell Sky News.

Read more:
Gove apologises for pandemic ‘errors’
Hancock accuses Cummings of lying to inquiry
Raab advised Johnson to get vaccine live on TV

Professor of innate immunity at the University of Cambridge, Clare Bryant, says people have become “complacent” about COVID – despite “lots of people having it at the moment”.

“There are lots of other germs around as well – flu is circulating and other colds,” she says.

Professor Nicolas Locker, a virologist at the Pirbright Institute, adds: “We’re going to see a fairly large rise in cases this winter.

“Not because the newer JN.1 sub-lineage is more problematic or severe, but because we’re losing our defences – protections afforded by our last set of boosters, and our immunity is waning.”

What should you do if you get COVID at Christmas?

Symptoms of COVID, flu, and other respiratory infections are “very similar”, according to the NHS.

They include: a continuous cough; high temperature, loss or change in sense of taste or smell; shortness of breath; unexplained tiredness; muscle aches; loss of appetite; headache; sore throat; runny or stuffy nose; and diarrhoea or vomiting.

If you have several symptoms but cannot access a COVID test, the NHS advises you to stay at home and avoid contact with other people until you feel better or no longer have a high temperature if you have one.

It is particularly important to avoid close contact with anyone high-risk – the elderly, clinically vulnerable and their carers, and pregnant women.

If you do have to leave home, the guidance suggests you “wear a well-fitting face covering made with multiple layers – or a surgical mask”, avoid crowded or poorly-ventilated spaces, cover your mouth when you sneeze or cough, wash your hands regularly, and avoid touching your face.

If you do a COVID test and the result is positive – official guidance recommends avoiding contact with others for five days after the day of your test for adults and three days for children.

You should also avoid meeting any clinically vulnerable people for 10 days after you take your test.

Over the Christmas period, this would mean isolating in a different room to elderly or vulnerable visitors – or asking them to stay at home instead.

What is JN.1 and how widespread is it in the UK?

JN.1 is a sub-lineage of the BA.2.86 Omicron variant.

It was first detected in Luxembourg in August, before spreading to the US, UK, France and other countries.

Its parent was first detected in Denmark in July, with the first BA.2.86 cases appearing in the UK in August. It is sometimes referred to as the “Pirola” variant – but the World Health Organisation hasn’t given it an official name, as it is still a type of Omicron.

JN.1 has one mutation in its spike protein (which dictates how easily it can infect our cells) compared to BA.2.86. But there are several other mutations elsewhere.

The latest genomic sequencing data, up until 21 November, shows it as the fastest-growing variant in the UK – with a weekly growth advantage of 84%, followed by its parent BA.2.86 at 23% and JD.1.1 (a sub-lineage of the XBB variant) at 22%.

JN.1 mutations will ‘probably make it more infectious’

Prof Bryant describes the various mutations in JN.1 as “interesting”, including some unseen since the Alpha and Beta variants in 2020 and 2021.

She says the changes are likely to mean JN.1 evades our immune systems more easily – and replicates faster.

“The change in the spike protein will probably correlate to it being more infectious,” she adds.

“And that’s what’s caused us the most problems so far – because you can’t control something that’s that infectious.”

Click to subscribe to the Sky News Daily wherever you get your podcasts

Professor Sheena Cruickshank, immunologist at the University of Manchester, agrees and adds that it could take longer to recover from – or cause more severe disease.

“One of the mutations JN.1 seems to have has the potential to help it better latch on to cells, making it better at infecting us,” she tells Sky News.

“That coupled with immune evasion mechanisms mean it may be tricky for our immune systems to get rid of.”

Professor Locker says, however, that so far there has been no indication of increased disease severity.

“I think we’re just seeing the natural evolution of COVID and I don’t think there’s anything right now we should be overly worried about,” he says.

“These are very small changes in comparison to the ones between Omicron and the previous set of variants. And we haven’t seen a change in symptoms or severity.”

Vaccines still likely to be effective against it

Prof Locker says that another reason not to be too concerned about JN.1 is vaccine protection.

Vaccines given as part of the current booster rollout have been updated to protect against the XBB.1.5 Omicron variant, which has also been proven to work against JN.1’s parent BA.2.86.

Prof Cruickshank adds that “by inference” this should also mean current vaccines work well against JN.1.

But all three scientists point to low vaccination levels as a more general cause of concern.

Now only the over 65s, care home residents, carers, health and social care workers, and the clinically vulnerable can get booster jabs on the NHS.

And of those groups, only around 50% are taking up the offer, meaning vaccine protection is relatively low.