Study Finds Six Distinct Types of Novel Coronavirus with Variable Symptoms

Aug, 2020 - By WMR

The novel coronavirus pandemic has spread to over 210 countries and as of 4:52 pm CEST, 28 July 2020, there have been 16,341,920 confirmed cases of COVID-19, including 650,805 deaths, globally, as reported to the World Health Organization. The novel coronavirus, first reported in the Chinese city of Wuhan, belongs to the Coronaviridae family of enveloped, positive-sense, single-stranded RNA viruses. Till date, no antiviral drug or a vaccine is available for the treatment of infections in humans caused due to coronaviruses.

Now, a team of researchers in Europe and U.S. from the King’s College London, Massachusetts General Hospital, U.S., and Lund University Diabetes Centre, Sweden, in collaboration with Zoe Global Limited, U.K., reported identification of six distinct symptom clusters of Covid-19. The study published in Medrxiv in June 2020 may aid in effective monitoring of Covid-19 symptoms. Such evidence suggests certain similarities in COVID-19 cases with and without symptoms and has prompted regulatory bodies to take necessary steps accordingly. As a result the U.S. Food and Drug Administration has granted LabCorp, a clinical laboratory company, an emergency use authorization to test people with no symptoms for the coronavirus.

The research team relied on COVID Symptom Study Smartphone app to accumulate data from a training dataset of completed cases and to perform unsupervised time series clustering over symptom presentation. The smartphone app was developed by Zoe Global Limited with input from clinicians and scientists from King’s College London and Massachusetts General Hospital. The participants in the study provided daily updates on symptoms and other related information.

The research team reported six clusters of Covid-19 symptoms. In the first cluster of flu-like symptoms and no fever, the patients also reported chest pain, cough, headache, loss of smell, muscle pains, and sore throat. The second cluster of flu-like symptoms with fever reported cough, headache, hoarseness, and loss of appetite and smell, along with sore throat. The third cluster was dubbed as gastrointestinal with symptoms ranging from headache, loss of appetite and smell chest pain to diarrhea and sore throat. The patients did not show symptoms of cough.

The fourth cluster was of level one severity with symptoms of cough, chest pain, fever, headache, hoarseness, loss of smell, and fatigue, whereas as severe level two cluster was evident with cough, confusion, hoarseness, headache, fever, loss of appetite and smell, sore throat, chest pain, fatigue, and muscle pain. The sixth cluster was level three severity with symptoms of abdominal pain, cough, chest pain, confusion, diarrhea, fatigue, fever, hoarseness, headache, loss of appetite and smell, sore throat, muscle pain, and shortness of breath. In cluster 1, 1.5% of people required breathing support and 16% ended up in hospital. 4.4%, 3.3%, 8.6%, 9.9%, and 19.8% of people required breathing support in cluster 2, 3, 4, 5, and 6, respectively. The number of patients that ended in hospital was the highest for cluster 6. The research can significantly impact care and monitoring of people who are at high risk of COVID-19 infection.