April 30, 2020 -- Most children who catch COVID-19 get few if any symptoms. They seem to shrug off fevers and coughs. Out of more than 1,000 reported infections in China and Singapore, only one -- a 13-month-old -- had a severe infection, and no child under 9 died.
Although this is obviously good news, it doesn’t mean that children aren’t playing a major role in the global pandemic.
They can still catch the virus, and it’s likely that they are contagious for some time, even if they feel fine.
The typical school kid comes into contact with more people -- and in closer physical contact -- every day than the typical adult, says William Hanage, PhD, an epidemiologist at the Harvard T.H. Chan School of Public Health. So if a child is infectious, they are likely to pass the virus on to more people.
The issue isn’t purely academic. Scientists need to understand how infectious children may be and whether that differs by age before deciding whether it makes sense to send them back to preschool, elementary, middle, high school, and college, says Hanage, adding that he’s very eager to get his own children back to school. “Unless we are able to thoroughly define the role of this age group in transmission, it’s very difficult to predict the likely consequences of reopening school.”
Other studies provide early hints, Hanage says, that age may be a factor in how many other people a child transmits the virus to.
“I think we are beginning to get some emerging evidence that young children may not play a great role” in transmitting the virus, he says, though it’s still “extremely premature” to draw firm conclusions about age. There’s a hint in the data, Hanage says, that adolescents who are infected are more likely to pass on the virus than younger children
New Study, New Data
A new study out of China, published Wednesday in Science, found that children under 15 were less susceptible to infection than people ages 15-64, and that those over 65 are extra susceptible.
The study concluded that although school closures in Wuhan province, where the outbreak began, were not enough on their own to stop the spread of COVID-19, “they can reduce peak incidence by 40-60% and delay the epidemic.”
The trend is likely to be the same in the United States, but there’s still too little known about the coronavirus, which has had an official name for only a few months.
“We really should fully understand the spectrum of infection in pediatric population in order to redefine in some ways our public health containment strategies,” says, Priya Soni, MD, a pediatric infectious disease expert at Cedars-Sinai Medical Center in Los Angeles.
She echoes Hanage’s call to keep school online-only for now. “The school closure piece is very important in my opinion to contain [the spread].”
Soni says she’s struck by one case report of a 6-month-old boy in Singapore. Both of his parents fell ill with COVID-19, so he was cared for at the hospital -- and his condition tracked -- for nearly 3 weeks in February.
He only had a mild fever for about an hour and no other symptoms, but the boy tested positive for COVID-19 and consistently shed high levels of the virus for 16 straight days. “On day 17, he became negative,” she says, suggesting that children who do get infected may be able to spread high levels of the virus for a long time.
Open Schools, Open Opportunities for Virus
Even if school-age children aren’t getting sick and are less infectious than elders, they can still pass on the virus to each other and to older people, Adrienne Randolph, MD, a senior doctor in critical care medicine at Boston Children’s Hospital, points out.
“There’s no way you can have school without adults there, and a lot of those adults are in the vulnerable population,” she says.
Cafeteria workers, for instance, are often low-income minorities, who have been particularly hard-hit by this pandemic; some teachers are at high risk because of their age or autoimmune status. And at high schools like the one her teenagers attend, Randolph says, many students take public transportation, potentially exposing themselves and others to the virus.
For college-age students, although they have only a very small risk of dying from the virus, some have become severely ill. And living in shared dorm rooms, eating in communal dining halls, and sitting in large classes can allow students to pass germs to friends, faculty, and workers, Hanage says.
“You really want to limit the pace with which the infection is building in the community,” he says. Bringing students back on campus risks sparking new outbreaks and overwhelming the health care system. One early study suggests that even keeping large classes online won’t stop the spread of the virus across a college campus.
For now, it’s best for all children to behave like everyone else during this pandemic, including social distancing and regular hand-washing, says Anna Sick-Samuels, MD, an instructor of pediatric infectious diseases at Johns Hopkins School of Medicine and an associate hospital epidemiologist at Johns Hopkins Hospital, both in Baltimore.
“Teaching children health practices such as frequent hand-washing and how to cover their face with a tissue or the crook of their elbow when they cough or sneeze are important for reducing the spread of infectious illnesses,” she says.
The CDC recommends that children under 2 shouldn’t wear a mask, but older ones may be required or advised to in public. If a child is too young to master these practices, it’s important to regularly clean “high-touch” surfaces and toys, Sick-Samuels says.