THE TWO main symptoms of Covid have changed, research shows.
For over a year, people have been alert to a new cough, loss of smell and taste and a high temperature.
🔵 Read our coronavirus live blog for the latest updates
But this now appears to be outdated and it could be causing undiagnosed people to spread the virus further.
If you are under 40, the signs to look for now are a headache, sore throat and runny nose, according to data.
If you are over 40, the key signs are a headache, runny nose and sneezing.
A leading professor says the Delta variant, first identified in India, seems to “working slightly differently”.
However, it could also be because Covid is currently causing an epidemic in young people, and symptoms are known to vary by age group.
The ZOE Covid Symptom Study has been tracking the Covid outbreak since March 2020, with millions of Brits reporting their symptoms on an app.
Prof Tim Spector, the lead on the study, told The Telegraph: “Since the start of May, we’ve been looking at the top symptoms and they are not the same as they were.
“Number one is headache followed by sore throat, runny nose and fever.
“All those are not the old classic symptoms, number five is cough, so it’s rarer and we don’t even see loss of smell coming into the top 10 anymore.
“This variant seems to be working slightly differently.”
A headache is recently showing to be the most common sign, affecting 66 per cent of under 40s and 53 per cent of over 40s.
Over 40s have less symptoms now and their top symptoms are very mild, due to vaccines.
None of their symptoms are the classic three of a cough, fever, or loss of smell.
A loss of taste or smell is no longer in the top 10 symptoms generally, the app has recently found.
Another leading infection survey in the UK found in February Covid is defined by symptoms of chills, loss of appetite, headache and muscle aches.
These four signs were together most strongly linked with being infected, according to the Imperial College London-led REACT study.
Prof Spector fears that many youngsters may be undiagnosed and spreading the virus further.
Most common Covid symptoms
The ZOE Covid Symptom Study app is currently seeing in the app data:
Under 40 year olds
Headache – 66.4 per cent
Sore throat – 53.6 per cent
Runny nose – 49.2 per cent
Fever – 42.1 per cent
Cough – 40 per cent
Over 40 year olds
Headache – 53.5 per cent
Runny nose – 36.3 per cent
Other – 34.5 per cent
Sneezing – 31.7 per cent
Sore throat – 30.3 per cent
The NHS says you should get a free Covid test if you have at least one of the three main symptoms of cough, temperature and loss of taste/smell.
But doctors – including Prof Spector – have long called for the list to be expanded and therefore catch more infected people.
Prof Spector continued: “Covid is acting differently now it’s more like a cold in this younger population and people aren’t realising this, and people might think they’ve got some sort of seasonal cold and they still go out to parties and they might spread it around.”
The Delta Covid variant has spread like wildfire across the UK within a matter of weeks.
It has the advantage of being more easily spread, by 60 per cent, and able to dodge vaccine immunity to some extent.
Because millions of under 30s are still not jabbed, and restrictions have been eased, it’s given the variant the perfect conditions to spread.
Cases are highest – and fastest growing – among those in their 20s.
Data from Public Health England shows cases have doubled in this age group, from 54 to 121 cases per 100,000 people.
Infections have also risen from 47 to 72 per 100,000 in people in their 30s.
Prof Spector said last week it was “clear that this is an epidemic among the unvaccinated and partially vaccinated populations in the UK”.
“And, due to the way vaccines have been rolled out, is largely affecting younger generations”, he warned.
It comes as Brits expect the Prime Minister to announce a delay in the June 21 unlocking.
Porn star’s George Floyd mural pic resurfaces after she was ‘found dead at 27’
Huge explosion at chemical plant sends plumes of black smoke into the air
Army paratroopers found dead ‘after involvement with illicit drugs’
Son killed with mom days after his hearing into deadly drunken boat crash
‘LOOK AT YOURSELVES’
Putin tells Joe ‘don’t be mad at the mirror if you’re ugly’ & slams US
NICE TO SEE YOU
Biden ‘breaks royal protocol AGAIN by wearing sunglasses to meet the Queen’
Health minister Ed Argar said the hope is to use a month-long window to get 10 million second jabs into arms.
But he admitted Boris Johnson could be forced to put back the end of lockdown until August.
Foreign secretary Dominic Raab also warned he couldn’t provide an “absolute guarantee” restrictions will definitely be lifted on July 19.