Covid symptoms: Fever is no longer the main sign of the spread of a new variant of the Kraken

In the early days of the pandemic, the main sign that you had Covid was a fever.

But as symptoms have evolved along with the virus, fever has become increasingly rare — and now, for the first time, it falls out of the top 20 symptoms, according to the ZOE Health Study.

Reducing symptoms of fever, a key indicator of infection severity, has raised hopes that the new highly contagious octopus subvariant currently circulating in the UK may be milder than its predecessors.

The number of daily symptomatic cases rose 57 percent in eight days to 75,771 on Wednesday, which just recalibrated its numbers due to changes in how Covid cases are reported, according to the ZOE.

This increase is partly due to a new variant officially named XBB.1.5. First identified in the UK in December, Covid-19 Genomics UK (COG-UK) has grown rapidly to account for 11 percent of new infections as of January 21.

And it is thought to have spread widely since then and is expected to dominate the UK and Europe by the end of the month. The cold snap and the return to schools and offices after Christmas also played a role, scientists say.

At its peak, fever was one of the “big three symptoms of Covid” – along with a persistent cough and loss of smell – in four of 10 symptomatic cases of the virus.

But now it accounts for less than 10 percent, with cough now the sixth most common symptom found in half of cases, and loss of smell as the 15th most common symptom at 17 percent, according to ZOE.

The new Big Three are one Sore throatA runny or stuffy nose AND sneeze – a change in symptoms that the public does not fully understand and means that many cases of Covid have been missed, a poll conducted last week showed.

Tim Spector, a professor at King’s College London who runs the ZOE app, says that while symptoms have changed a lot during the pandemic, they have barely changed in the past few months, with the exception of fever. .

As a result, while it can be very difficult to tell a cold from Covid-19 without a test, as many of the symptoms overlap, it becomes much easier to tell if you have the flu or not, as high fevers are common in people with colds but are common in people with flu.

“I think everyone was expecting another wave before the end of winter and this is what it looks like. We can hope it’s pretty mild and the symptoms don’t look bad just yet. Fever occurs in less than 10 percent of all cases and has disappeared from the top 20 symptoms,” said Professor Spector. I.

“Fever is a sign of seriousness, but it’s too early to say that XXB.1.5 is less serious. The main symptoms, such as a sore throat, runny nose or nasal congestion, have not changed much over the past few months, so you cannot distinguish them from the symptoms of a cold.

“But less than one in ten people get a fever. This means a stronger distinction between Covid and the flu – so if you have a fever, you are much more likely to get the flu.”

Professor Lawrence Young, a virologist at the University of Warwick, said it’s not clear at this point if XXB.1.5 is less serious than the other variants, but it certainly doesn’t seem more serious.

“The change in symptoms is difficult to localize – is it a direct consequence of the evolution of the virus or is it related to the level of immunity of the population from previous infections and vaccinations?” He said.

“There is no evidence that XBB.1.5 is more pathogenic [harmful] than other variants of Omicron, but it is much more infectious and has a high level of immune escape. According to WHO, XBB.1.5. “does not carry any known mutation associated with a possible change in severity.”

A study published last week by Swansea University and Cardiff Metropolitan University found that the majority of people with Covid symptoms behave as usual and take few precautions to avoid spreading the virus to others.

Confusion about symptoms was seen as one of the main reasons as many did not know they had Covid symptoms and mistook their illness for a cold or flu.

Only one in six adults with respiratory symptoms were tested to determine if it was Covid, a cold or the flu, according to a survey conducted in December and January. Only one in ten wore a mask and the same number is in self-isolation, while only one in twenty went to the doctor.

The study found that high fevers, persistent coughs and fevers continue to prompt most people to take more precautions. These are the Big Three symptoms that were identified at the beginning of the pandemic and have remained in people’s minds.

Top 20 symptoms of Covid

1. Sore throat (occurs in 57% of cases)

2. Cold (57%)

3. Stuffy nose (56%)

4. Sneezing (53%)

5. Headache (53%)

6. Do not expectorate phlegm (50%)

7. Cough with phlegm (40%)

8. Hoarse voice 34%)

9. Muscle pain (29%)

10. Dizziness (19%)

11. Pain in the eyes (19%)

12. Fatigue (18%)

13. Swollen glands (17%)

14. Altered smell (17%)

15. Loss of smell (17%)

16. Pain in the ears (16%)

17. Shortness of breath (14%)

18. Chest pain (13%)

19. Chills or chills (13%)

20. Pain in the shoulder joint (11%).

Source: ZOE Health Survey.

However, the study found that a sore throat, runny nose or nasal congestion, which are newer but now common symptoms of Covid, caused far fewer people to take precautions as people were more likely to assume they had a cold.

“At the beginning of the pandemic, we were bombarded with messages and ads urging us to be vigilant and get tested if we had a loss of smell or taste, a new persistent cough or fever,” says Simon Williams of Swansea University.

“A lot less has been reported about what the new options look like — for example, Covid is now much less likely to be accompanied by a fever,” he said.

Dr Williams said not understanding the full breadth of Covid symptoms and how they change is of particular concern: “We found that people are much more likely to get tested for Covid if they have a persistent cough, high fever, or loss of taste or smell.

“This is understandable as these were early symptoms of the Big Three early variants. In psychology, we call this the primacy effect, where early information gets stuck in our heads,” he said.

Prof Spector said that while cases are currently on the rise, they are coming from low levels, hitting a 15-month low in January.

He expects cases to continue to rise in the coming weeks to about the same level as during the last wave, at about 150,000 cases of symptomatic infection per day. This is well below the previous record of around 300,000, but still higher than during most of the pandemic.

This week, the ZOE changed the way it estimates the number of infections after it found that the numbers, which are usually calculated seven to 10 days ahead of official national statistics, differ from those of the ONS after they were calculated for most of the pandemic.

This is because ZOE scores are based on the number of people saying they are positive versus the number of people saying they are negative. For most of the pandemic, this method has proven accurate, but it has dwindled in recent weeks as tests have effectively halted and only the sickest people are doing them.

As a result, the imbalance between reported positive and negative results has widened, making the ZOE estimates excessively high, Professor Spector said.

However, he stressed that the app accurately displays the time and relative wave size of the past few weeks faster than any other data source.

“People can totally rely on trends — when do waves start, where do they go and what are the symptoms. In the end, it doesn’t matter if it’s about 100,000 people a day or 70,000 a day. It is about the direction of movement and whether the risk is high, medium or low. And it was absolutely right,” he said.

The latest data from the Office for National Statistics showed that the number of Covid cases in England, Wales, Northern Ireland and Scotland declined in the week ending January 24, 2023. This is in line with this week’s ZOE data, which also showed a decline.