How children's coronavirus symptoms compare with those of the flu
- As flu season arrives, researchers are trying to distinguish symptoms to tell the difference between seasonal flu and the novel coronavirus.
- Children in particular tend to have irregular or no symptoms of coronavirus, making it possible for them to spread the disease without being sick themselves.
- A new study found that children with the coronavirus showed more symptoms like fever and digestive upset than those with the flu, but rates of hospitalization were about the same.
- Experts say we still can't tell the different based on symptoms alone.
As school starts and flu season nears, research suggests we still don't know enough about how the novel coronavirus affects children to differentiate it from the flu, at least based on symptoms alone.
Children with COVID-19 have many of the same symptoms as those with flu, and are hospitalized at approximately the same rates, according to a retrospective study published September 8 in JAMA Network Open.
Researchers at Children's National Hospital looked at data collected between March and May from 315 children diagnosed with COVID-19 and 1,402 children diagnosed with the flu.
Comparing symptoms, rates of hospitalization, and the number of patients needing intensive care and/or ventilators, they found children had similar outcomes, regardless of the diagnosis.
To their surprise, the symptoms were broadly the same, with some minor distinctions. They found children actually experienced more shortness of breath from flu than COVID-19, and those with COVID-19 more often experienced digestive symptoms.
Flu and coronavirus can have nearly identical symptoms
According to the study, the most common coronavirus symptoms were ones that are generally associated with flu: fever, cough, digestive issues like vomiting and diarrhea, body aches, headaches, and chest pain.
More children with coronavirus showed those symptoms than children with the flu — 76% of COVID-19 patients studied had a fever, compared with 55% of flu patients. And more than one in four coronavirus patients (26%) reported vomiting or diarrhea, compared to just 12% of flu patients.
But to the researchers' surprise, there wasn't any significant difference in rates of shortness of breath between coronavirus and flu patients.
"I didn't see this coming when I was thinking about doing the study," Dr. Xiaoyan Song, co-author of the study and director of Infection Control and Epidemiology at Children's National, said in a press release. "It took several rounds of thinking and combing through the data to convince myself that this was the conclusion."
Unfortunately, that means researchers still don't have an easy way to tell the difference between the two illnesses without testing, Song told Business Insider.
"It's still very hard to distinguish the two populations solely by symptoms," Song said. "From a clinical management perspective, it confirmed our fear that we can't really eyeball the distinction, we have to really have to rely on diagnostic testing."
Children have similar outcomes from flu and COVID-19
Researchers didn't find any statistically significant difference in outcomes between the flu and the novel coronavirus.
Both resulted in comparable rates of hospitalization — 21% of children with the flu were hospitalized, compared to 17% with COVID-19. They also found similar rates of intensive care needed (7% flu, 5.7% coronavirus) and need for ventilators (1.9% flu, 3.2% coronavirus).
Children hospitalized with coronavirus infection, though, were more likely to have underlying medical conditions, including neurological conditions such as seizures or developmental delay. That wasn't the case for flu.
We still don't understand the 'silent spreaders' of COVID-19
An additional complication, though, is asymptomatic cases.
There's evidence that children may be particularly likely to spread coronavirus without ever becoming sick themselves, according to previous studies.
This study screened out COVID-19 patients without symptoms, since there isn't comparable data for flu patients, but researchers are currently analyzing asymptomatic patients for future studies.
School shutdowns could keep the flu season — and coronavirus — under control, the researchers say
The hospital didn't see any cases of children with both flu and COVID-19, although that's possible.
Part of the reason for this was that flu cases plummeted in March — one of the final months of the flu season — when schools were closed to curb coronavirus spread.
"We observed zero influenza in our hospital. It was very unprecedented, it just disappeared," Song said.
That's promising evidence that interventions could help slow or even end what we thing of as "flu season" weeks earlier than expected.
Next, the team is studying how to best carry out school closures, to reduce the spread of flu and coronavirus, without the social and economic burdens of shutting down businesses and social contact.
For now, Song urged everyone to maintain physical distance from others, wear masks, wash their hands, and get a flu shot early.
Read more:
Children with asymptomatic coronavirus cases could shed the virus for weeks, a study found