Experts Wonder Why COVID-19 Symptoms are Not Severe in Children, Infants


COVID-19 has the entire world on edge, but perhaps nobody is as concerned as parents. It can seem impossible to shield children from illnesses when germs are unpredictable and omnipresent. And the fact that the coronavirus is spreading unhindered in most countries is enough to give parents anxiety.

But here’s a bit of optimistic news for moms and dads: The coronavirus doesn’t seem to impact babies and children as severely. A World Health Organisation (WHO) – China Joint Mission report on the virus, published in mid-February 2020, found that children aged 18 or younger accounted for only 2.4 percent of all cases in China. On top of that, a new study by the American Academy of Pediatrics (AAP) of pediatric cases of the COVID-19 in China confirms what the WHO found, adding that “over 90 percent of all infected children and infants were asymptomatic, mild, or moderate cases.”

And while the first infant death related to COVID-19 in the U.S. was reported in Illinois on March 28, the limited research available suggests “that children with confirmed COVID-19 have generally presented with mild symptoms,” says the Centers of Disease Control and Prevention (CDC). Severe complications seem to be exceptionally rare in kids.

Here’s what parents need to know about the coronavirus and children, plus tips for preventing the respiratory illness that originated in Wuhan, China.

What are COVID-19 Symptoms in Children?

Most children with the virus have mild cold-like symptoms, such as fever, runny nose, and cough, according to the CDC. Gastrointestinal issues, like vomiting and diarrhea, may also occur. Some children have no symptoms whatsoever.

The COVID-19 complications appear to be uncommon for those under 18 years old—even in small infants. In fact, the WHO-China Joint Mission report states that only 2.5 percent of children diagnosed with the coronavirus had “severe” symptoms, and 0.2 percent were considered “critical.” The recorded complications include acute respiratory distress syndrome and septic shock, according to the CDC.

How Are Babies and Infants Being Affected?

Since babies don’t have fully formed immune systems, it would make sense that they’d be severely affected by the virus. According to the 2020 AAP study of those affected in China, while kids of all ages are susceptible, young children might be more vulnerable. The proportion of severe and critical cases was 10.6 percent for infants under one and 7.3 percent for kids ages one to five, compared to three percent for 15- to 18-year-olds. Like older children, however, babies display mild symptoms in most cases, but might also be asymptomatic.

In China, for example, only nine infants had confirmed coronavirus cases between December 8 and February 6, according to a February 14 report published in JAMA. The infants were between 1 month and 11 months old, but none required intensive care. No severe complications were reported either.

But while this is great news, it might lead to another problem: Babies might unknowingly spread coronavirus to their parents or caregivers. Take this case in Singapore published in the journal Clinical Infectious Diseases, which involves a six-month-old baby. After a mother and nanny were hospitalised with pneumonia—and the father came down with a fever and sore throat—hospital staff found the baby had high levels of the COVID-19 in his “throat, blood, and stool,” according to the Los Angeles Times. The baby was asymptomatic, which caused the coronavirus to spread easily to caregivers. He didn’t develop any symptoms during a subsequent hospital stay (with the exception of a very short-lived fever).

These “silent cases” could help spread the coronavirus even further, which is particularly worrisome for grandparents and caregivers with compromised immune systems.

Why is the COVID-19 Mild for Children?

Since the coronavirus is a novel disease, experts still don’t know many things about it—including why children have lower transmission rates and milder symptoms. “We don’t definitively know the reason,” says K.C. Rondello, M.D., MPH, CEM, clinical associate professor at the College of Nursing and Public Health at Adelphi University. “Everyone from virologists to epidemiologists to infectious disease doctors are completely stymied as to why we’re seeing this phenomenon.”

Here are a few theories, however, within the medical community:

Kids Have a Better Immune Response

One theory is that children have better immune responses than adults, which helps them fight off the coronavirus. “Children’s immune systems are not fully functional until later in their development. As a result, they have a considerably stronger and more robust immune response to pathogens than adults,” explains Dr. Rondello.

What’s more, “The death rate for COVID-19 is higher among individuals with certain pre-existing conditions, such as cardiovascular disease, diabetes, and cancer. This may help explain why many children seem to be at lower risk, since they are less likely to have these types of preexisting conditions,” says Aimee Ferraro, Ph.D., faculty member for Walden University’s Master of Public Health (MPH) programme.

Many experts tentatively support the hypothesis, but there’s also a hitch: The coronavirus seems to spare most infants even though their immune systems aren’t fully formed yet.

Experts Might Not Be Identifying All Coronavirus Cases

Robert Frenck, Medical Director of the Division of Infectious Diseases at Cincinnati Children’s Hospital, says that a reporting bias might be to blame. When the coronavirus first emerged, doctors in America and China were only testing people with severe symptoms. But they’ve since found that milder, cold-like symptoms may also occur.

“It’s possible that the coronavirus causes a spectrum of illnesses, and that medical organisations are only identifying the more serious ones,” summarizes Dr. Frenck. Children might not be getting diagnosed if they’re only experiencing mild symptoms—which means the coronavirus may be affecting more children (and people in general) than reported.

Kids Could Have “Immunological Cross-Protection”

According to Dr. Rondello, a number of different viruses could give you the common cold—including milder forms of coronavirus. “Children get colds a lot, so they’re already being exposed to more benign, less intense coronaviruses. They could have potentially built immunity to them,” he says. Dr. Rondello calls this “immunological cross-protection.”

Kids Could Have Less Exposure

Other experts say kids might simply have less exposure to the coronavirus, since infected adults are more careful to prevent the spread of sickness, according to Business Insider. Plus, the article adds, more adults probably visited the presumed source of the coronavirus: the seafood and live animal market in Wuhan, China.  (Culled from