Little is known about how the COVID-19 coronavirus affects young children, and a small Chinese study provided few answers.
A research letter published in by Zhi-Jiang Zhang, MD, PhD, of Wuhan University, and colleagues examined nine infants with COVID-19, and found two commonalities in all cases: the illness seemed to be mild, and family clustering occurred for all infants, meaning all were from a household with at least one infected family member.
"This shows that infants are getting infected, but at least in this [study], all had mild illness. Some had no symptoms," said Waleed Javaid, MD, director of Infection Prevention and Control at Mount Sinai Downtown in New York City.
"This is a retrospective study, so it's limited by information documented and that can be a flaw, as some information may be missing," Javaid, who was not involved with the research, told .
Even CDC officials have seemed stumped when asked how COVID-19 may affect children.
"There have been multiple hypotheses why there haven't been that many cases in children," Nancy Messonnier, MD, director of CDC's National Center for Immunization and Respiratory Diseases, said at a recent press event. "One hypothesis is there have been [infections], but it's been mild illness."
Messonnier added that if sustained transmission occurred in the U.S., keeping children home from school might be an option, given the availability of "teleschooling." This would potentially limit opportunities for transmission.
Recent studies from China have suggested that older people with preexisting chronic illnesses are most at risk for severe COVID-19 illness and death.
Zhang and colleagues noted that COVID-19 is more likely to affect older men, especially those with chronic comorbidities, but "few infections in children have been reported." This study examined data from hospitalized infants from Dec. 8, 2019 to Feb. 6, 2020 in China. Infants ranged from age 1 month to 11 months.
Clinical syndromes varied, with four infants presenting with fever, two with mild upper respiratory symptoms, and one described with no symptoms, who was only tested because a family member had COVID-19. Time from admission to diagnosis was 1-3 days, the authors said.
Seven infants were either from Wuhan or had family members visiting Wuhan, while one had no link to Wuhan and one had no information available. None required intensive care, mechanical ventilation, or had severe complications.
The investigators noted that seven of nine infants were girls, which is unusual given that prior research found higher percentages of infection in men versus women.
"Whether female infants may be more susceptible to COVID-19 infection requires further study," Zhang and co-authors wrote.
They concluded that especially given family clustering, adult caregivers should "wear masks, wash hands before close contact, and sterilize the infants' toys and tableware."
"We need to be aware that infants will get infected by someone close to them, hence one needs to consider limiting contact with infants and children when one is sick," Javaid noted.
Zhang and colleagues added that infants with infected family members should be monitored and evaluated to "ensure a timely diagnosis."
Disclosures
This study was funded by the National Natural Science Foundation of China and the Fundamental Research Funds for the Central Universities.
The authors disclosed no conflicts of interest.
Primary Source
JAMA
Wei M, et al "Novel Coronavirus Infection in Hospitalized Infants Under 1 Year of Age in China" JAMA 2020; DOI: 10.1001/jama.2020.2131.