Experts from the University of Liverpool have contributed to an article published in The BMJ calling for the UK to expand its official list of symptoms for defining Covid-19.
They argue that limiting symptomatic testing to those with these official symptoms “will miss or delay identification of many Covid-19 cases, hampering efforts to interrupt transmission” and that expanding symptom list in line with other countries could improve the UK’s pandemic response.
During the Covid-19 pandemic the British public has been told to self-isolate and get a test if they have a high fever, a new continuous cough, or a loss or change to their sense of smell or taste.
However the article’s authors, who include the University of Liverpool’s Professor Calum Semple and Professor Iain Buchan, say many people don’t have these official symptoms, initially, or ever, and other symptoms often manifest earlier.
Professor Iain Buchan, Executive Dean of the Institute of Population Health, said: “If you feel very tired, have a headache, runny nose or tummy upset it might now be COVID, so get a test.”
“The official symptoms of high temperature, a new, continuous cough or loss or change to your sense of smell or taste are still very important – and you are currently eligible for specific types of tests if you have these symptoms. But anyone can get a test at any time via other routes, and more people with cold-like symptoms, or just not feeling right, need to get tested in order to help stop the spread of the virus.”
“These changes in common symptoms are expected as people who are older are more likely to be vaccinated and younger people tend to have a wider variety of symptoms that start earlier – when most transmission of the virus takes place.”
The authors point out that the World Health Organization and Centers for Disease Control and Prevention already include nine and 11 more case defining symptoms respectively than the UK – and the European Centre for Disease Prevention and Control describes a breadth of symptoms associated with mild-to-moderate Covid-19 – with the most commonly reported being headache, weakness or tiredness, muscle aches, runny nose, appetite loss and sore throat.
These unofficial symptoms are also more common in young unvaccinated, or partially vaccinated people, who are most likely to pass the virus on.
The authors write that it seems counterintuitive, therefore to have no official UK guidance on wider Covid-19 symptoms, or to offer different testing routes for those with official symptoms and those with no symptoms, with nothing in between.
They acknowledge that expanding the case definition is likely to increase demand for testing and numbers self-isolating, and would require careful implementation.
However, new data suggests that testing people based on combinations of unofficial and official symptoms could be used to help identify more cases sooner without overwhelming testing capacity.
Vaccinations alone are unlikely to end the pandemic, they write. New, more transmissible and (partially) vaccine resistant variants may spread through susceptible populations causing high hospitalisation rates.
Inequalities in vaccination are also shifting the burden of disease and disruption to the most disadvantaged communities, who are also harmed most by covid-19 restrictions, they add.
“To reopen society with greater speed and fairness, control of transmission must improve. This starts with an expanded and more context appropriate case definition and rests on adaptive, locally grounded, and information-led public health responses,” they conclude.
The full article, whose lead author is University College London’s Alex Crozier, is available on the BMJ website.