The government health agency is looking into the super cold as Britons report being struck down with “the worst cold ever.”
Calls to 111 and GP visits for cold and flu symptoms are on the rise meaning colds are back in the lead up to winter, according to the UK Health Security Agency (UKHSA).
The NHS have received more calls and online assessments for cold, flu, coughs and difficulty breathing since the last week of September.
The UKHSA says it is continually monitoring respiratory viruses and that, although cases are expected to increase, there has not yet been a significant spike in confirmed cases of flu.
Experts advise it is unlikely to represent a new strain of the coronavirus and instead could be the result of 18 months of social distancing reducing levels of immunity against seasonal colds.
People are urged not to self diagnose but to seek a Covid test if they suffer from a cough, temperature or loss of taste and smell.
Deputy Chief Medical Officer Professor Jonathan Van-Tam said: “Not many people got flu last year because of Covid-19 restrictions, so there isn’t as much natural immunity in our communities as usual.
I have succumbed to the cold going around London at the moment (no, not Covid). This is the first time I've had a cold in about a year thanks to social distancing. Were they always this bad or am I just not used to it?
— Sascha O'Sullivan (@saschaosullivan) September 27, 2021
“We will see flu circulate this winter; it might be higher than usual and that makes it a significant public health concern.
“Covid-19 will still be circulating and with more people mixing indoors, sadly some increases are possible.”
This winter, the UK will see Covid and flu circulating together for the first time.
However, health officials say it is too early to tell whether this flu season will see a higher number of cases than in previous years before the pandemic.
Prof Van-Tam urged for people to “take this seriously” and defend themselves by getting the annual flu jab and Covid booster when called.
“Both these viruses are serious,” he said.
“They can both spread easily, cause hospitalisation and they can both be fatal. It is really important that people get their vaccines as soon as they can.”
Londoners have complained of “grim” cold symptoms with one person commenting on social media that they were “out for a week.”
Another said: “I have succumbed to the cold going around London at the moment. Were they always this bad or am I just not used to it?”
Dr Yvonne Young, London’s Deputy Director for Health Protection at the UK Health Security Agency, said London should expect more cases of flu and Covid-like viruses as we move towards winter.
“Respiratory infections and common colds thrive in winter thanks to the lower temperatures and people mixing and socialising more indoors,” she said.
“In London we are expecting cases of viruses like Covid-19 and influenza to increase as we move through the colder months.”
On Wednesday, the UK recorded its highest daily Covid cases since July with 42,776 more infections as deaths climbed by 136.
Dr Young advised people to continue regular hand washing and wearing a face mask in crowded or enclosed places to avoid illness.
Several respiratory viruses are circulating at this time of year, including RSV and rhinovirus, as to be expected coming into winter and social mixing meaning viruses can spread more easily.
Confirmed cases of RSV have remained low since the a recent spike in July.