Anyone with a loss of taste or smell – or noticeable changes – should now self-isolate for seven days, under new Covid-19 rules from the UK’s chief medical officers.

– What has changed?

The list of major symptoms of coronavirus has been amended to include a loss of taste or smell, or noticeable changes to both.

It means that anyone with a loss of taste or smell, a high temperature or cough should now take action to prevent spreading the virus.

They should stay home for seven days from when their first symptom appears, while anyone in their household should stay home for 14 days.

– Hang on, haven’t I heard about this before?

Ear, nose and throat specialists have been warning for weeks that loss of smell and taste are symptoms of coronavirus.

Professor Tim Spector, from King’s College London, whose team is tracking the symptoms of hundreds of thousands of people across the UK, also said on April 1 that people with those symptoms should stay at home.

England’s deputy chief medical officer, Professor Jonathan Van-Tam, insists scientific advisers have been monitoring the reports, but have only just finished working through the detail on what impact it may have.

– Does this mean people have been walking around with these symptoms and infecting others?

Yes. But they are not the only ones, seeing as experts know that a proportion of infected people pass on Covid-19 despite showing no symptoms at all.

Professor Spector says 50,000 to 70,000 people in the UK currently have loss of taste and smell as a Covid-19 symptom but have only been told to stay at home from today.

– Are health officials considering including other symptoms on the list?

Not at the moment. Government scientific advisers are aware of other Covid-19 symptoms but say they are not major ones and are generally common.

Other reported symptoms of coronavirus include muscle pain, abdominal pain, diarrhoea, fatigue, nausea, sore throat and chills, headache and rash.

The current advice is that if people have these symptoms and no others, there is no need to stay home in isolation.

– What do scientists say?

The move to include loss of taste or smell has been broadly welcomed.

Professor Carl Philpott, from the University of East Anglia, said it was good news but the UK had moved much later than other European countries and at least two weeks after the World Health Organisation (WHO) added the symptoms to their list.

He said: “This will hopefully now be another measure by which the pandemic can be contained, especially as in some people it may be the only symptom, or may precede other symptoms.

“This is particularly pertinent in healthcare workers where reports of smell and taste disturbances have been commonplace, meaning the transfer of infection from colleagues to each other and to uninfected patients will have been happening unchecked.”