Changing nature of Covid: Is it just a regular winter bug now?

Before the pandemic, Sally enjoyed regular trips abroad and played golf three or four times a week, socialising with the other members at her club.

Now in her mid-70s, she enjoys good health. But despite having been vaccinated against Covid, Sally says the virus has changed her approach to life.

"I've not been on a plane since the pandemic started," she says. "I just don't think it is worth the risk.

"I still play lots of golf - and in the summer, I enjoy having a drink on the terrace. But I don't really do any socialising inside. I skip the Christmas parties and other events when the weather turns."

Sally is not alone, with research suggesting anxiety over Covid continues. And in recent weeks, it appears to have intensified, with internet searches for Covid having shot up with news of a new variant and a rise in hospital admissions.

But there is plenty of evidence to suggest the virus is on its way to becoming just another respiratory bug to contend with, alongside flu and others maybe lesser known, such as respiratory syncytial virus (RSV), rhinorvirus and adenovirus.

All carry risks - particularly to those with certain health conditions and compromised immune systems, who are advised to take precautions, including getting the available vaccinations and limiting contact with people with symptoms.

Last winter there were estimated to be more flu deaths than Covid ones, in England - just over 14,000 compared with 10,000 - according to the UK Health Security Agency.

That comes as no surprise to Prof Paul Hunter, an infectious-diseases expert at the University of East Anglia.

The immunity to serious illness built up from vaccination and infection means the death rate per Covid infection is now well below that of flu, he says.

Although there was a lot more Covid around in 2022, with a series of peaks over the 12 months, rather than it being largely confined to the winter months like other respiratory viruses - so for the year as a whole, the Covid death toll would outstrip that of flu.

But, crucially, that trend has not been repeated in 2023. Instead, there is a much more seasonal pattern to the virus, with a long lull during spring and summer.

Covid is "well on the way" to becoming seasonal, Prof Hunter says, with flu likely to cause more deaths from now on. And eventually, Covid will become "just another cause of the common cold", like the other coronaviruses that circulate.

Prof Adam Kucharski, who advised the government during the pandemic, agrees there are positive signs but remains a little more cautious.

"With flu, we see a lot of pre-existing immunity," Prof Kucharski says, "which makes it difficult to spread outside of winter."

The colder months tip the balance, he says, because of more indoor mixing and lower temperatures, which affect susceptibility to infection as well as allowing the virus to survive for longer outside.

"The question with Covid is whether it can evolve enough to escape the immunity built up and cause problems outside of winter," Prof Kucharski says.

"We are seeing hints of seasonality but I wouldn't say we're definitely there."

But people can find it difficult to put Covid in context, Prof Kucharski says, pointing out there is still much more data on Covid than other respiratory viruses.

"Data is good for scientists but it can cause alarm when interpreted wrongly," Prof Kucharski says. "With recent new variants, we've sometimes seen people exaggerate the level of risk - that's not helpful."

Prof Mike Tildesley, a modeller in infectious diseases, at the University of Warwick, is also encouraged by changes in Covid but says it could still end up causing more deaths than flu this winter.

"There was quite a rebound for flu last year," he says, "partly because immunity was down following a few years of not much flu circulating - so we may see the picture change this winter."

It is also hard to judge to what extent Covid deaths are coming on top - or instead - of flu. Combined, the number of Covid and flu deaths last winter was on a par with the worst two winters of the past decade.

The changing nature of Covid also poses an interesting question about testing - is there any point to it?

The era of free Covid tests may be over but plenty of people still test when they feel ill. Although, the experts have their doubts about whether this is entirely necessary.

"If you have symptoms," Prof Tildesley says, "the question you have to ask yourself is whether you would do anything different if you tested and it wasn't Covid.

"If there is one thing we have learnt from the pandemic, it is the importance of trying to stay away from people if you are ill with a respiratory virus. That is as true for flu and other respiratory viruses as it is for Covid."

Prof Hunter agrees: ""The only situation where [Covid testing] is useful is if you are vulnerable with a condition* that would benefit from antivirals."

So what continues to hold some people back?

Dr Martyn Quigley, a psychologist from Swansea University, says: "Covid had a huge impact on our lives - unlike anything we have lived through, for most - and for some, uncertainty and worry persist even though the risks have changed.

"There are still lots of social cues - hand sanitiser, signs and screens in shops - that remind us of what happened.

"It is similar with data. It is that unique history that is associated with Covid that induces worry and concern. It will take a long time for that to go for those affected in this way."

Update 31st October: We have added a paragraph referring to the risk from respiratory bugs for vulnerable groups and the precautions they are advised to take. Separately, on the 16th October Professor Hunter's quote was edited at his request to use the word 'condition' instead of 'lung condition'.