Researchers found a symptom that needs more attention in diagnosing COVID-19

Analysis by medical researchers of the University of Tartu indicates that focusing solely on respiratory symptoms may mean that COVID-19 is diagnosed late or left undiagnosed. For people older than 50, more attention must be paid to diarrhoea and fever without cough or runny nose.

Based on the data of the seroepidemiological study KoroSero-EST-1 conducted in Saaremaa and Õismäe (district of Tallinn), medical researchers from the University of Tartu analysed the symptoms of people who had antibodies to the coronavirus and people who did not. Of the 1,960 subjects, 73 had developed antibodies and 1,887 had not.

Hiie Soeorg, Research Fellow of Medical Microbiology of the University of Tartu, said that one of the main symptoms connected to COVID-19 – fever – had been reported by half of people with antibodies and about one third of people without antibodies. The other main symptom, cough, had been reported by 43% of people with antibodies and 70% of people without antibodies. Runny nose was reported by 57% of people with antibodies and 69% of people without antibodies and sore throat by 36% and 62%, respectively. What is significant, however, is the occurrence of diarrhoea: it was reported by approximately one third of people with antibodies and less than a quarter of those who did not have antibodies.

The analysis of the symptoms of 157 people who had suffered from an acute respiratory disease showed that people with antibodies reported sore throat and cough less frequently than people without antibodies. Among people who had antibodies against SARS-CoV-2, only one person in five had had an acute respiratory disease, meaning that most of them did not experience that. “Looking at 55 people older than 50, we noticed that the existence of antibodies mostly correlated with having diarrhoea and fever and not having a runny nose and cough,” said Soeorg.

“The importance of diarrhoea as a symptom among people older than 50 reveals that if we focus solely on respiratory symptoms, infection with coronavirus may be diagnosed late or left undiagnosed,“ emphasised Soeorg.

Hiie Soeorg made the presentation on symptoms suggestive of coronavirus based on antibody studies at the University of Tartu conference “Intelligent adaptation to the coronavirus“.