New research has boiled down the most probable order in which COVID-19 symptoms first appear.
The earliest sign of the coronavirus will most likely be a fever in infected patients, followed by a cough and muscle pain, according to the study conducted by the University of Southern California published in the Frontiers in Public Health journal Thursday.
People will then experience nausea or vomiting and diarrhea.
The latest findings are a major breakthrough in studying the coronavirus since patients will now be able to more quickly identify and treat the disease.
“This order is especially important to know when we have overlapping cycles of illnesses like the flu that coincide with infections of COVID-19,” Peter Kuhn, a professor of biological sciences and medicine who worked on the study, said in a statement. “Doctors can determine what steps to take to care for the patient, and they may prevent the patient’s condition from worsening.”
Establishing a diagnosis early is key to stopping the virus before it gets more serious.
“Given that there are now better approaches to treatments for COVID-19, identifying patients earlier could reduce hospitalization time,” said Joseph Larsen, a doctoral candidate and the lead researcher on the study. “The order of the symptoms matter. 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.”
The initial symptoms of the coronavirus are very similar to other respiratory illnesses such as MERS and SARS, but it’s the timing of gastrointestinal issues that makes COVID-19 easier to single out.
“The upper GI tract (i.e., nausea/vomiting) seems to be affected before the lower GI tract (i.e., diarrhea) in COVID-19, which is the opposite from MERS and SARS,” the scientists wrote in the study.
Larsen, along with faculty advisers Kuhn and James Hicks, conducted the study at the USC Michelson Center for Convergent Bioscience’s Convergent Science Institute in Cancer.
The USC researchers analyzed data collected by the World Health Organization in China between Feb. 16 and 24 from more than 55,000 confirmed coronavirus cases. The scientists also took a look at nearly 1,100 cases gathered from Dec. 11 to Jan. 29 by the China Medical Treatment Expert Group via the National Health Commission of China.
They then compared the numbers to influenza symptom data of 2,470 cases in North America, Europe, and the Southern Hemisphere that were reported to health authorities from 1994 to 1998.