Omicron has resulted in a higher hospitalization rate for babies in the U.K. than seen for previous variants of COVID-19, though most hospital stays were short, researchers said.
Infants under the age of one accounted for 42 percent of children hospitalized during the Omicron wave, compared with thirty percent in May to mid-December when the Delta variant was prevalent, the research team said in data presented on Friday. Outcomes for the hospitalized babies have been positive, however, with no deaths, less need for oxygen and proportionally fewer intensive-care admissions than during the Delta wave.
The data add to evidence out of the U.S. signaling a rise in child hospitalizations due to Omicron. However, the UK team said it also fits into what would normally be expected during a busy winter of respiratory infections, and that caution in the treatment of children with fever may account for some of the higher admission rate.
“I completely accept that any hospital admission is a stress for the parents, but these are not particularly sick children,” said Calum Semple, a professor of child health and outbreak medicine at the University of Liverpool. The babies spent an average of just under two days in the hospital, he said.
A National Health Service England analysis of the data was also “extremely reassuring,” said Russell Viner, a professor of child and adolescent health at University College London. Most of the hospitalized children were less than three months old, an age when doctors tend to treat fevers with an abundance of caution. About half of them received no treatment, but were merely observed, he said.
Children’s small upper airways make them more susceptible to some types of respiratory illnesses. There’s also evidence that Omicron affects that part of the respiratory tract more than previous variants have, he said.
The hospitalized babies largely had a fever, often with a cough. They were healthy infants without other medical conditions, the researchers said.
“For pediatricians, this is absolutely our bread-and-butter kind of work,” said Camilla Kingdon, president of the Royal College of Pediatrics and Child Health. “I’m very confident that even if we saw a rise from the current level of activity, we would be able to cope.”
The higher rate of infant hospitalizations probably can’t be explained only by a lack of vaccines for young children or a high spread in communities, because there wasn’t a corresponding jump in hospitalizations for older toddlers who also have no access to a vaccine, said Christina Pagel, a professor of operational research at University College London. She wasn’t involved with the study but reviewed the results.
“We urgently need to understand more about what might be causing this increase,” Pagel said. She also pointed out that the data show children from more economically deprived areas are far more likely to hospitalized, a discrepancy that has only widened in the Omicron wave.