These 7 symptoms best predict a novel coronavirus infection, epidemiologists say
Brooklyn NeustaeterCTVNews.ca Writer
@bneustaeter ContactPublished Thursday, September 30, 2021 8:53AM EDTLast Updated Thursday, September 30, 2021 10:01PM EDThttps://imasdk.googleapis.com/js/core/bridge3.482.0_en.html#goog_57992435Volume 90% Tam warns Canada facing a grim fall NOW PLAYINGDr. Theresa Tam issued a new warning, saying that the country could face a grim fall if more Canadians don’t get vaccinated.CTV National News: Canada’s worst COVID-19 wave NOW PLAYINGNew COVID-19 modelling shows that without more vaccinations cases could skyrocket this month. 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TORONTO — A team of epidemiologists in the U.K. has determined that a set of seven symptoms, when expressed together, best predict SARS-CoV-2, the virus that causes COVID-19, in the community.
The study, published Tuesday in peer-reviewed journal PLOS Medicine, reports that the symptoms of loss or change of smell, loss or change of taste, fever, new persistent cough, chills, appetite loss, and muscle aches can be used to maximize the detection of COVID-19.
However, the study notes that not all of these symptoms are used in the U.K. to determine eligibility for PCR testing.
To decide who should be tested in Canada, health care professionals assess people based on their symptoms (mild or severe), underlying medical condition or risk of exposure to the virus.
“In order to improve PCR positivity detection rates and consequently improve control of viral transmission via isolation measures, we would propose to extend the list of symptoms used for triage to all seven symptoms we identified,” the authors wrote.
The authors noted that “rapid detection” of coronavirus infection in the community is key to controlling transmission.
When testing capacity is limited, the study says that tests should be used in the “most efficient way possible,” including using the “most informative” symptoms for determining who to test.
The study, conducted by researchers from Imperial College London, looked at positive throat and nose swab tests from 1,147,345 volunteers in England aged five and older.
According to the study, the data was collected over eight testing rounds conducted between June 2020 and January 2021 as part of REal-time Assessment of Community Transmission, a series of studies using home testing to improve understanding of how COVID-19 is progressing across England.
The participants were asked about their symptoms in the week prior to testing. From this, the researchers determined the seven symptoms that can jointly predict COVID-19 positivity.
The study found that testing people in the community with at least one of the seven symptoms gave sensitivity, specificity, and positive predictive values of 74 per cent, 64 per cent, and 9.7 per cent, respectively.
Modelling conducted by the researchers suggests that using all seven symptoms to determine PCR test allocation would result in 30 to 40 per cent of symptomatic individuals in England being eligible for a test, compaired to 10 per cent currently.
In addition, the study reported that if all those deemed eligible were tested, this would result in the detection of 70 to 75 per cent of positive cases.
Study author and University College London professor Paul Elliot said there is a need for “clear testing criteria” given that signs of COVID-19 infection include symptoms that are commonly found in other illnesses, such as influenza.
“These 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,” Elliot said in a press release.
“I hope that our findings on the most informative symptoms mean that the testing program can take advantage of the available evidence, helping to optimise the detection of infected people,” he added.