What is Novel coronavirus (2019-nCoV)?
Video / WHO
Coming down with coronavirus can result in many symptoms – or even none at all.
So researchers say knowing in which order they first appear will help doctors identify Covid-19 patients sooner and make better treatment decisions.
Scientists from the University of Southern California have revealed the order symptoms are likely to arise – fever, cough and muscle pain, then nausea and/or vomiting, then diarrhoea.
They say knowing the order could also help patients seek treatment quicker or decide to self-isolate.
Doctors could also rule out other illnesses or plan how to treat patients, according to the findings published in the journal Frontiers in Public Health this month.
"This order is especially important to know when we have overlapping cycles of illnesses like the flu that coincide with infections of Covid-19," said Peter Kuhn, professor of medicine, biomedical engineering, and aerospace and mechanical engineering.
"Doctors can determine what steps to take to care for the patient, and they may prevent the patient's condition from worsening."
Lead author of the study, doctoral candidate Joseph Larsen, said given there were now better approaches to treatments for Covid-19, identifying patients earlier could reduce hospitalisation time.
He said fever and cough were frequently associated with a variety of respiratory illnesses, including Middle East respiratory syndrome (Mers) and severe acute respiratory syndrome (Sars).
But he said the timing and symptoms in the upper and lower gastrointestinal tract set Covid-19 apart.
"The upper GI tract (nausea/vomiting) seems to be affected before the lower GI tract (diarrhoea) in Covid-19, which is the opposite from Mers and Sars," the scientists wrote.
They were able to predict the order of symptoms from the rates of symptom incidence of more than 55,000 confirmed coronavirus cases in China, all of which were collected from February 16 to 24 by the World Health Organisation.
They also studied a dataset of nearly 1100 cases collected from December 11 to January 29 by the China Medical Treatment Expert Group.
To compare the order of Covid-19 symptoms to influenza, the researchers examined data from 2470 cases in North America, Europe and the Southern Hemisphere that were reported to health authorities from 1994 to 1998.
"The order of the symptoms matter," Larsen said.
"Knowing that each illness progresses differently means that doctors can identify sooner whether someone likely has Covid-19, or another illness, which can help them make better treatment decisions."
