Scientists are cautiously optimistic that the variant may be a sign the virus is losing its power, despite the high infection figures
Once again, many countries is experiencing a festive season hit by waves of Covid-19 infections. Last year, Christmas and the new year were spoiled by the appearance of the Alpha variant.
This time, it is Omicron that has sent case numbers soaring. Christmas cancellations have swept through the restaurants, pubs and clubs and left the country on the brink of another bleak New Year as the the authorities warn once more that it is facing the threat of being overwhelmed by spiralling numbers of seriously ill patients.
The scenario has raised fears that this now represents the shape of Christmases to come. Social restrictions and lockdown threats could become our normal festive fare.
It is a dispiriting prospect. But is it realistic? Are we justified in drawing close parallels between this Christmas and last year’s? These are key questions because, in trying to answer them, we may also find clues to the likely path of the entire pandemic.
Is the virus likely to lose its power to cause severe illness?
Many scientists believe evidence is now suggesting that this idea may be correct. Recent studies in Scotland, England and South Africa all point in this direction. “My gut feeling is that this variant is the first step in a process by which the virus adapts to the human population to produce more benign symptoms,” says Dr Julian Tang, professor of Respiratory Sciences at Leicester University. “In a sense, it is to the virus’s advantage if it affects people in a way that that they don’t get too sick – because then they can walk around and mingle in society and spread the virus even more.”
So will Covid-19 end up behaving like flu?
Some health officials have predicted that Covid-19 could end up behaving like influenza, which requires a new vaccine to deal with new strains that appear every year. However, Professor Martin Hibberd, of the London School of Hygiene and Tropical Medicine, argues that coronaviruses – like those that already cause common colds – do not behave this way: “They do not appear as new strains every year. The reason we get colds in winter is because our immunity to coronaviruses does not last very long. And this virus seems to be more similar to those that cause common colds. In other words, we may still need to think about giving vaccines to protect against Covid-19 every year because immunity will always slip.”
That does not mean we face “doom and gloom” for the next five years, adds Tang. “I think the virus will evolve itself out of the pandemic strain very soon and become milder, more transmissible to the point where you may only need to think about vaccinating the more vulnerable members of the population.”
How close does this year’s outbreak parallel that of last winter?
At first glance, the two years look strikingly similar, with case numbers rocketing in only a few weeks in the UK. However, hospitalisations and deaths from Covid-19 remain very low so far this year, with latest research suggesting that the new variant appears to trigger fewer cases of severe illness than its viral predecessors.
Scientists have generally treated these results studies as good news but have also counselled caution. Daily Covid-19 case numbers are still rising – they reached a record 122,000 on Friday – and it was estimated that 1.7 million people had Covid-19 in the UK last week.
Are there noticeable differences in the ages of those affected by Omicron?
Crucially, most of the new cases have occurred in young adults, which has led some researchers to warn that if Omicron starts to affect older – more vulnerable – people in greater numbers, hospitalisations could still jump. On the other hand, a huge number of people – especially the elderly – have now been give vaccines and boosters and will have gained considerable protection against Omicron. It remains to be seen how these different factors affect figures. At present, data is still being gathered and it is too early to be sure. At the same time, policy decisions to protect public health still have to be taken.
The problem is highlighted by infectious disease epidemiologist Professor Mark Woolhouse of Edinburgh University. “There is inevitably a lag between infection and hospitalisation,” he told the journal Nature last week. “But in the meantime, policy decisions have to be made, and that is not straightforward.”