A headache and a runny nose should be added to the official list of Covid symptoms, a government adviser has said.

Professor Calum Semple, who sits on the Scientific Advisory Group for Emergencies (Sage), argued that the current definition risked missing many cases.

Classic symptoms of Covid-19, according to the NHS, are a high temperature, a new continuous cough, and/or a loss or change to a person’s sense of smell or taste.

However, the most commonly reported symptoms by people taking part in the Office for National Statistics Covid-19 Infection Survey are a cough, headache and fatigue.

The latest ONS release showed that 61 per cent of people who tested positive reported symptoms.

Of these, 42 per cent had a cough, 39 per cent reported a headache and 38 per cent reported fatigue. Muscle ache was reported by a quarter of people and 32 per cent reported having a sore throat. Meanwhile, a third reported a fever, while 21 per cent reported loss of smell and 15 per cent reported loss of taste.

Fatigue was the most common symptom reported as part of individuals’ experience of long Covid

A separate study – the Zoe Covid Symptom study – recently reported that a headache, sore throat and runny nose were now the most commonly reported symptoms.

Writing in the British Medical Journal, Prof Semple and a team of other scientists suggested that limiting testing to only people with fever, cough and a change in taste or smell could “hamper efforts to interrupt transmission” of the virus.

The group argued that increasing the symptom list could improve Britain’s pandemic response by expanding the criteria for self-isolation and eligibility for symptomatic testing.

They said that the “narrow” case definition “limits” the early detection of contagious people which restricts the efforts of the Test and Trace programme.

Non-traditional symptoms “often manifest earlier”, they added.

The US Centres for Disease Control lists 11 more symptoms than the UK, while the World Health Organisation includes nine more.

The testing capabilities in the UK are now able to facilitate people with a broader spectrum of symptoms, they added.

They conceded that testing people with a single non-specific symptom could overwhelm testing capacity in the UK, but “combinations of symptoms could be used to help identify more cases sooner without overwhelming testing capacity”.

The group also said that some studies have suggested that people of different age groups display different symptoms.

Some people with non-traditional symptoms already “bypass” the current rules which state that those with classic symptoms should get a PCR test. “Legitimising this choice could be helpful,” they added.

They authors wrote: “The UK’s decision to adopt a narrow case definition was based on ease of communication, avoiding confusion with other infections and preserving testing capacity. This situation is now different – testing capacity is high.”

But they said that communication with the public is key, given that only half can currently identify the classic symptoms.

They concluded: “Covid-19 is associated with a wide range of symptoms. Many patients do not experience the UK’s official case-defining symptoms, initially, or ever, and other symptoms often manifest earlier.

“Limiting the symptomatic testing to those with these official symptoms will miss or delay identification of many Covid-19 cases, hampering efforts to interrupt transmission.

“Expanding the clinical case definition of Covid-19, the criteria for self-isolation, and eligibility for symptomatic testing could improve the UK’s pandemic response.”

BBC presenter Andrew Marr – who caught Covid even after being fully vaccinated – is one of those whose first symptoms appeared like a cold, including sneezing, sore throat and a slight headache.

Two days after his symptoms started, he began to feel "seriously ill" and started to show traditional Covid symptoms including fever and loss of smell.