Omicron COVID-19 variant ‘less severe’ than Delta for kids under 5, new U.S. study says

Children under the age of five who are infected with the Omicron COVID-19 variant have less risk of severe health outcomes than those infected with the Delta variant, according to research done by the Case Western Reserve University in the U.S. 

The peer-reviewed research, which was published on April 1 in JAMA Pediatrics, focuses on the health outcomes of this age group, which is not yet eligible for vaccination against COVID-19.

The research team examined clinical health outcomes for pediatric patients during a 14-day window following infection. Among the factors they reviewed were: emergency room visits, hospitalizations, ICU admissions and mechanical ventilation use.

“The major conclusion to our research was that many more children were infected with Omicron when compared to Delta, but the children who are infected are not impacted as severely,” Pamela Davis, one of the study’s researchers at the Case Western Reserve School of Medicine, said in a press release.

“However, because there are so many more children infected, our hospitals were affected over the winter months by an influx of young children,” she added.

The study shows that the Omicron variant is six to eight times more infectious than the Delta variant. The severe health outcomes ranged from a 16 per cent lower risk for emergency room visits to 85 per cent less risk for mechanical ventilation.

Also, about 1.8 per cent of children infected with Omicron were hospitalized, compared to 3.3 per cent with Delta, the study says.

To arrive at these findings, the team said it went through the electronic health records of more than 651,640 children in the United States who got infected between September 2021 and January 2022.

“We saw the number of hospitalizations within this age group skyrocket in January of this year because the infection rate of Omicron is about 10 to 15 times compared to that of the Delta variant,” Rong Xu, a professor of biomedical informatics who was also part of the research team, said in a press release.

Xu said “Omicron is less severe than Delta,” with its severity on children’s bodies and health 16 to 85 per cent less.

She also explained that since so many unvaccinated children were infected, “the long-term effects of COVID-19 infections on the brain, heart, immune systems and other organs of children remain unknown and worrisome.”

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The U.S. Centers for Disease Control and Prevention (CDC) recommends those aged five and older receive a COVID-19 vaccine, and fully vaccinated people 12 and older receive a booster shot.

In early February, Pfizer asked the U.S. to authorize extra-low doses of its COVID-19 vaccine for children under five.

The vaccine manufacturer aims to give children as young as six months shots that contain one-tenth of the dose given to adults.

The U.S. CDC says on its website that children between ages six months through four years may soon become eligible for the Pfizer-BioNTech vaccine but does not specify when.

Canadian children under five remain unvaccinated, with Pfizer yet to seek approval from Health Canada for its vaccine for that age group.

In a statement to Global News on Feb. 1, the health agency said it expects Pfizer to file their submission shortly but there have been no updates since.

Health Canada approved Pfizer’s COVID-19 vaccine for use in children between six and 11 years old in November of last year. It has also recently authorized Moderna’s vaccine for that age group, the same which has been done in Australia and the European Union.

Moderna last year said its two-dose vaccine generated virus-neutralizing antibodies in children aged six to 11 years old and its safety was comparable to that seen in clinical trials of adolescents and adults.

Children who get COVID-19 usually have no symptoms or only mild symptoms, according to Health Canada.

Although they’re less likely than adults to get very sick, some do experience serious outcomes. These can include hospitalization or, in rare cases, death.

There’s also a risk of developing multisystem inflammatory syndrome in children (MIS-C) after COVID-19 infection.

According to the Mayo Clinic, MISC-C affects the organs and tissues, such as the heart or lungs, which become severely inflamed. It is a rare but serious condition that can occur weeks after infection.

Children may also be at risk of post-COVID-19 condition, known as ‘long COVID.’

“Unvaccinated people are more likely to get sick from COVID-19 compared to those who are vaccinated. Vaccinating those who interact with children, including caregivers, will help to protect children,” Health Canada stated.

-With files from Reuters, The Associated Press, and Global’s Amanda Conolly