The most prevalent symptoms of the Omicron variant now match those of the common cold, with calls for the government to update its public health messages to include more likely symptoms of Covid.
The most common symptoms reported among Zoe Covid app users were a runny nose, headache, fatigue, sneezing and sore throat, according to the study’s most recent analysis of confirmed cases in London.
Half of those who report cold-like symptoms have also tested positive for Covid, with no clear difference in symptoms reported for Delta or Omicron infections. But only about half of infected users also reported the “three classic symptoms of fever, cough, or loss of smell or taste,” according to Zoe’s analysis.
Zoe’s analysis was supported by Sage’s board of science advisers at a meeting on Thursday. The committee said there was “preliminary evidence” of changes in symptoms accompanying Omicron infections, as loss of taste or smell “seems to be reported less frequently.”
Professor Tim Spector, lead scientist on the Zoe Covid study, said public messaging needs to recognize that Covid symptoms would be more like a cold for many of those infected.
Spector said he was shocked at what he called “misinformation” in the government‘s latest stay-at-home guidance on symptoms of Covid.
“Zoe’s data clearly shows that the most important symptoms are no longer a new continuous cough, high temperature, or loss of taste or smell.
“For most people, a positive Omicron case will look a lot more like a cold, starting with a sore throat, runny nose. and a headache. Just ask a friend who recently tested positive to find out, ”Spector, professor of genetic epidemiology at King’s College London, told the PA News Agency.
“We urgently need to change public messages to save lives, as half of people with cold-like symptoms now have Covid. “
The NHS website currently lists “main symptoms of coronavirus” as high temperature; a new continuous cough, including a heavy cough for more than an hour; a loss or change in your sense of smell or taste. He advises people with any of the three symptoms to take a PCR test as soon as possible and self-isolate.
Peter Openshaw, Professor of Experimental Medicine at Imperial College London, speaking in his personal capacity, said there was evidence the virus was changing its behavior, in terms of the cells it infected, resulting in a change symptoms.
Recent data, including a study from Hong Kong, found that Omicron was less capable of infecting deep lung tissue but more capable of infecting upper bronchial tissue.
“It appears to be heading for a virus that infects higher up in the respiratory tract and therefore adapts to be more transmissible in part because it changes the types of cells it infects,” Openshaw said.
“This would go hand in hand with producing cold-like symptoms. These lab studies support what the Zoe app is telling us.
Openshaw said it would be “reasonable” to update the list of Covid symptoms: “The semi-lockdown has been terrible for colds, they are struggling to survive. So if you have a cold right now, there’s about a 50% chance that it is in fact Covid. “