Led by an international delegation, the Global Consortium for Chemosensory Research (GCCR) survey was launched in response to anecdotal reports of smell and taste loss in people who have tested positive for Covid-19.

UEA smell expert Prof Carl Philpot, from Norwich Medical School, is one of the research group’s members. He has also been surveying local hospital workers during the pandemic.

He said: “Our group of international smell and taste researchers united to study how, when and why people are experiencing a loss of smell and taste, and what it can tell us about coronavirus.

“We are collecting data on Covid-19 from people in 50 countries all around the world – and it all points to the fact that smell loss is a symptom.

“We have found that it particularly affects some demographics, such as women in their 30s and 40s. This is different to what we would normally see when people present with anosmia  following a virus - that tends to be people who are in an older age group, more commonly in their 60s and 70s.

“Our research and that from many other centres shows that for some, it can be the only symptom, or accompanied by or precede other mild symptoms.

“It adds weight to the findings from King’s College London, who launched a Covid-19 symptom tracker app,” he added.

“So today’s announcement that the CMOs have now recognised smell and taste disturbances is extremely welcome, albeit much later than other European counterparts and at least two weeks after the WHO added it to their list.

“It means that those calling NHS 111 with sudden loss of smell will now be told they are likely to have Covid-19, are eligible for a test, and should self-isolate.

“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.

“There will also be a recognition that although many patients will recover these senses, the need for ongoing support will be faced by a minority in whom these sensory losses persist, such as that provided by our charity Fifth Sense.

Prof Barry Smith from the University of London, the UK lead for the GCCR, said: “If enough people are able to tells us about their sudden loss of smell or taste, this will provide vital clues that could be part of the story about the prevalence of the virus in the population – information the Government can all upon before mass antibody testing is available.”

The UK researchers in GCCR, who are made up of clinicians, sensory scientists and patient advocates “have contributed at every turn” according to Prof Smith, “by publishing scientific findings, writing letters to leading medical journals, and by informing the public directly through social media, newspaper articles and podcasts.”

The UK GCCR team hope that this new recognition of the importance of smell, and the effect of its loss on people’s lives, will encourage further work into olfaction, uniting the interests of ENT practitioners, sensory scientists and the many patients who have already contributed so much to understanding the link between Covid-19 and loss of smell.