Covid symptoms: A fever is no longer a top sign as new ‘Kraken’ variant spreads

In the early days of the pandemic, running a temperature was a key sign that you had Covid.

But as symptoms have evolved with the virus, a high temperature has become less and less common – and has now fallen out of the top 20 list of symptoms for the first time, according to data from the ZOE Health Study.

The decline in fever symptoms, a key indicator of the severity of an infection, has raised hopes that the new, highly contagious, Kraken subvariant that is sweeping the UK at the moment, could be milder than its predecessors.

Daily symptomatic cases jumped by 57 per cent in eight days to 75,771 on Wednesday, according to ZOE – which has just recalibrated its figures because of changes in the ways covid cases are reported.

It is an increase that has been fuelled, in part, by the new variant, which is officially named XBB.1.5.

This was first identified in the UK in December and grew rapidly to account for 11 per cent of new infections on 21 January, according to Covid-19 Genomics UK, or COG-UK.

And it is believed to have spread extensively since then and is predicted to become dominant in the UK and Europe by the end of the month. The colder weather and return to schools and offices after Christmas have also played a role, scientists said.

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

But it now accounts for less than 10 per cent , with coughing now only the sixth most common symptom – being found in half of cases – and loss of smell slipping to the 15th most common, affecting 17 per cent, according to ZOE.

The new ‘big three’ are a sore throat, a runny or blocked nose and sneezing – a change in symptoms that is not fully understood by the public and has led to many cases of Covid being missed, a study showed last week.

Tim Spector, the King’s College London professor who runs the ZOE app, says that, while symptoms have changed a great deal over the course of the pandemic, they have largely stayed the same in the past few months – with fever being the one notable exception.

As a result, while it can be very hard to distinguish between a cold and Covid without taking a test – because so many of the symptoms overlap – it is becoming much easier to tell whether you have flu or not as high temperatures are extremely rare in people with colds but common in those with flu.

“I think everyone was expecting another wave before the winter’s out and this looks like it. We can hope that it’s fairly mild and so far the symptoms are not looking bad. Fever is less than 10 per cent of all cases, it’s dropped out of the top 20 symptoms,” Professor Spector told i.

“Fever is a marker of severity – but it is still too early to say whether XXB.1.5 is less severe,” he said.

“The main symptoms – such as sore throat and runny or blocked nose – haven’t really changed much in the last few months, so you can’t really tell it from cold symptoms.

“But less than one in ten people getting any sort of fever. This signifies increased differentiation between Covid and flu – so if you’ve got fever it’s much more likely that you’ve got flu.”

Professor Lawrence Young, a virologist at Warwick University, said it is unclear at the moment whether XXB.1.5 is less severe than other variants but certainly appears to be no more serious.

“Changing symptoms are hard to pin down – is this a direct effect of virus evolution or due to the level of immunity in the population due to previous infections and vaccinations?” he asks.

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

A study published by Swansea University and Cardiff Metropolitan University last week found that most people with Covid symptoms are behaving much as they normally do, taking few precautions to prevent passing the virus on to others, a study has found.

Confusion about symptoms was seen as one of the main reasons, with many not realising they had Covid symptoms and mistaking their illness for a cold or the flu.

Only one in six adults with respiratory symptoms took a test to determine whether it was Covid, a cold or the flu, according to the survey taken in December and January.

And just one in 10 wore a mask and the same proportion isolated – while only one in 20 sought help from a doctor.

The survey found that a high temperature, continuous cough and fever are still most likely to lead people to take more precautions. These are the ‘big three’ symptoms identified near the beginning of the pandemic that have stuck in the popular imagination.

However, sore throats or runny or blocked noses, which are more recent but now common Covid symptoms, led to far fewer people taking precautions, as people are more likely to assume they have a cold, the survey found.

“Early in the pandemic we were bombarded with messages and ads saying to stay alert and take a test if we had a loss of smell or taste, a new continuous cough or a fever,” said Simon Williams, of Swansea University.

“There has been much less communication around what the newer variants look like – Covid now is much less likely to be accompanied by a fever for example,” he said.

Dr Williams said the lack of understanding about the full breadth of Covid symptoms – and the way they are changing – was particularly concerning: “We found people were much more likely to take a Covid test if they had a continuous cough, high temperature or a loss of taste or smell.

“This is understandable, given these were the ‘big three’ early symptoms from early variants. In psychology we call this the ‘primacy effect’ – where early information sticks in our heads,” he said.

Professor Spector said that although cases are soaring at the moment, they are coming from a low base, having hit a 15-month low in January.

He expects cases to continue to rise for the next few weeks to around the same level they hit in the last wave, which would put them at around 150,000 daily symptomatic infections. This is well below the previous record of around 300,000 but still higher than they have been for much of the pandemic.

This week, ZOE has changed the way it estimates infection numbers are finding that it’s numbers – which are typically calculated seven to 10 days before the Official for National Statistics – were diverging from the ONS numbers after tracking them closely for most of the pandemic.

That’s because ZOE estimates are based on the number of people who report they are positive compared to the number who say they are negative. For most of the pandemic this has proved an accurate method but in recent weeks it has become less so as the number of tests being taken virtually grinds to a halt, with only the most ill typically taking them.

As a result, the imbalance between positives and negatives reported has widened, leading ZOE estimates to be too high, Professor Spector says,

However, he insists that in recent weeks the app has continued to accurately reflect the timing and relative magnitude of waves and faster than any other data source.

“People can absolutely rely on the trends – when the waves are happening, where the waves are going and what the symptoms are. Whether infections are at 100,000 people a day, or 70,000 a day, ultimately doesn’t really matter. It’s about the direction of travel and whether the risk is high, medium or low. And that’s been totally accurate,” he said.

The latest figures from the Office for National Statistics showed that Covid cases were declining in England, Wales, Northern Ireland and Scotland in the week ending 24 January 2023.

This tallies with ZOE’s numbers for that week, which also showed a decline.

The top 20 symptoms of Covid in the UK at the moment, according to ZOE Health Studay:

1.Sore throat (found in 57% of cases) - 2.Runny nose (57%) - 3.Blocked nose (56%) -4.Sneezing (53%) - 5.Headache (53%) - 6. Cough no phlegm (50%) -7.Cough with phlegm (40%)

8.Hoarse voice 34%) - 9.Muscle pain aches (29%) - 10.Dizzy (19%) - 11.Eye soreness (19%) -12.Fatigue (18%) - 13.Swollen glands (17%) - 14. Altered smell (17%)- 15.Loss of smell (17%)

16.Earache (16%) - 17. shortness of breath (14%) - 18. Chest pain tightness (13%) - 19.Chills or shivers (13%) - 20. Joint pain shoulders (11%)  

Reference: Story by Tom Bawden 

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Urine test could detect two cancers with '99%' success rate - revolutionary research

Researchers, led by Dr Ho Sang Jung, collaborated on the project to improve cancer diagnostics. Dr Jung said: "In the case of cancers where the diagnosis method is not well known, such as pancreatic cancer, it is difficult to detect and the survival rate after initial diagnosis is low. "Since early diagnosis is the most important for incurable diseases such as cancer, we expect this technology to provide a new diagnostic method."

For the research study, the team manufactured a strip-type sensor that detects metabolites.

Urine samples of cancer patients and non-cancer patients were compared in terms of metabolic components.

When cancer cells proliferate in the body, they secrete different metabolites into the urine due to abnormal metabolism.

The strip sensor "succeeded in distinguishing up to 99 percent of prostate cancer and pancreatic cancer patients from normal people".

The rapid cancer patient screening tool is also highly accessible, as urine is a "biological sample that anyone can easily" provide.

The authors noted: "In addition, since the production price of the strip-type sensor is less than KRW 100 per unit, it is expected that it can be used for mass inspection."

Currently, the research team is gradually increasing the types of cancer that could be diagnosed by analysing the urine of bowel cancer and lung cancer patients.

Prostate cancer diagnosis

Prostate Cancer UK highlighted a urine test that highlights the activity of the PCA3 gene.

"CA3 is a gene that is active in all prostate cells but it's very active in prostate cancer cells," the charity elaborates.

"At the moment the PCA3 test is only available in a few private hospitals and clinics, as we still need more research about how well it works."

Do book a doctor's appointment if you identify with any of the following possible signs of prostate cancer, as pointed out by the NHS:

Reference: Daily Express: Story by Chanel Georgina •