The largest study conducted so far on children with the new coronavirus provides very early evidence that males and infants may face an increased risk of infection or serious illness.
The U.S. Centers for Disease Control and Prevention released the study on Monday, which looked at over 2,500 coronavirus cases among children under the age of 18 in the United States between February 12 and April 2. This is the largest research sample of children with coronavirus to date.
Overall, the data suggest that children are less likely to develop coronavirus symptoms than adults. Of all the cases reported in the United States, only 1.7% were children, although they represent 22% of the population.
Of the children for whom complete information was available, only 73% developed fever, cough or shortness of breath. This is compared to 93% of adults reported in the same time frame, between 18 and 64 years old.
This supports previous research conducted by the Chinese CDC, according to which most infected children had mild or asymptomatic cases.
But some children develop serious illnesses and 147 of the patients in the new CDC study were hospitalized, with five sent to ICU. Three children died.
Infants in the United States had a much higher hospitalization rate than any other age group. Of the 95 children, 62% were hospitalized. The estimated percentage for children aged 1 to 17 was at most 14 percent.
“We know that children’s immune responses evolve over time,” said Dr. Yvonne Maldonado, president of the American Academy of Pediatrics committee of infectious diseases. Time. “The first year of life, infants do not have the same robust immune response as older children and adults.”
Could “biological factors” make males more sensitive to COVID-19?
Increasing research has suggested that men die of COVID-19 at higher rates than women.
The World Health Organization reported that as of March 20, men accounted for around 70% of coronavirus deaths in Western Europe.
Data from five countries with some of the world’s largest outbreaks suggest that men are 50% more likely to die of women after being diagnosed with COVID-19, according to an analysis by CNN and the group on March 20 Global Health 50/50 academic research.
An analysis of over 25,000 coronavirus cases from the Istituto Superiore di Sanità in Rome found that male coronavirus patients in Italy had a mortality rate of 8 percent, compared to 5 percent of Italian women. The same analysis found that men accounted for a slight majority of coronavirus cases in Italy: around 58 percent.
Some experts pointed out that men have higher smoking rates, poor hygiene on average and higher rates of pre-existing conditions such as diabetes than women.
But 57 percent of the COVID-19 children in the CDC study were male. Infected infants were also predominantly male. This “suggests that biological factors could play a role in any difference in COVID-19’s susceptibility to sex,” the study authors wrote.
However, this research is preliminary and the authors are working with limited information. Of the 2,572 pediatric cases they analyzed, only 9.4% included information on patients’ symptoms and only 33% indicated whether or not they had been hospitalized.
The study authors recommended that doctors maintain “a high suspicion index” for children who may have COVID-19, particularly for infants and children with underlying conditions.
“We have to be very cautious overall,” Maldonado told Time. “We still don’t know what we’re dealing with here.”
This article was originally published by Business Insider.
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