A new study has identified four new symptoms in a study of COVID-19. Currently, health bodies across the world, although slightly varied, generally report a fever or high temperature, a new continuous cough, and changes to your sense of taste and smell as the classic and main symptoms of COVID-19. The loss of taste and smell was added after the first two after further study found this to also be a common symptom. Imperial College London’s REACT study, which examined over one million people between June 2020 and January 2021 in the United Kingdom, has found four new common symptoms, which are – chills, loss of appetite, headache and muscle aches.
The data was collected via swab tests and questionnaires in just over a six month period. The researchers conducting the study found an association between reporting any or all of these new symptoms, and/or experiencing other symptoms previously identified as being linked to the coronavirus and a positive COVID-19 test result. The more symptoms a person had, the more likely they would be COVID-19 positive as a result. The New Scientist reported that these new symptoms showed some variation across different age groups, stating: ‘chills were linked with infection across all age groups, whereas headaches were reported mainly in children aged 5-17, appetite loss in adults over 18 and muscle aches in those aged 18-54. Infected 5-17 year olds were also less likely to report experiencing fever, persistent cough and appetite loss, in comparison with adults.’
The study also examined the new B.1.1.7 variant, which is now the dominant strain of the coronavirus in the UK and is reportedly more transmissible and may lead to a higher mortality rate. The REACT study examined whether the these new symptoms were consistent before and after the emergence of the B.1.1.7 variant. Finding that, the symptoms were largely similar, with the exception that in January 2021, when the B.1.1.7 variant accounted for 87% of infections, a loss or change in the sense of smell was less indicative of a COVID-19 infection. This was in comparison to November and December 2020, where the B.1.1.7 variant only covered approximately 16% of infections. At the same time those who reported a persistent cough and tested positive appeared to increase in January 2020.
Although an increased likelihood of infection was connected with these symptoms, the study also highlighted that approximately 60% of people did not report symptoms in the week leading up to their test.
In the UK, currently, people are taking COVID-19 tests if they have any of the three ‘classic’ symptoms outlined by the NHS – a high temperature, new persistent cough and loss or change to the sense of smell or taste. Although less common symptoms which have been reported elsewhere could be linked to COVID-19, and a shortness of breath and/or difficulty breathing has been linked to more severe cases, the ‘classic’ three symptoms remain the main identifiers and basis for testing. The researchers estimate that this testing approach, named ‘pillar two’ by the UK government and healthcare program, picks up around 50% of all symptomatic infections if everyone took a test, yet if the new, additional symptoms were included in the list and people were also encouraged to take a test if they have the new symptoms, the researchers predict that approximately 75% of symptomatic infections could be identified.
Director of the REACT program at Imperial College London, Professor Paul Elliot said in a statement: “These new findings suggest many people with Covid-19 won’t be getting tested – and therefore won’t be self-isolating – because their symptoms don’t match those used in current public health guidance to help identify infected people. We understand that there is a need for clear testing criteria, and that including lots of symptoms which are commonly found in other illnesses like seasonal flu could risk people self-isolating unnecessarily. I hope that our findings on the most informative symptoms mean that the testing program can take advantage of the most up-to-date evidence, helping to identify more infected people.”
Joshua Elliott one of the researchers on the study at Imperial College London, also added: “As the epidemic progresses and new variants emerge, it’s essential that we keep monitoring how the virus affects people so that testing programs meet changing needs. We hope that our data will help inform testing guidance and the development of systems which could help better identify people who should take a Covid-19 test based on their symptoms.”