Why the delta variant is hitting kids hard in the U.S. and how we can prevent that in Canada

As back-to-school season approaches, many Canadian parents are alarmed by reports of unprecedented cases of COVID-19 among children and teens as well as increasedhospitalizationsin parts of the U.S.

According to the American Academy of Pediatrics, the majority of these illnesses aredriven by the delta variant, which it has called"hyper infectious."

Although the delta variant is on the rise in Canadatoo, pediatric infectious disease specialists and public health experts say we're not in the same boat as U.S. hotspots and that there are measures we can take to avoid getting there.

What's happening in the U.S.?

"Right now, things are really bad in the southern and southeastern parts of the United States," said Dr. David Kimberlin, with the Children's Hospital of Alabama anda professor of pediatrics at the University of Alabama at Birmingham.

"We have more pediatric cases, more pediatric hospitalizations, more pediatric severe disease cases than we've ever had throughout this pandemic," he said.

"What we're experiencing is much worse than it was even in the dark days of January and Februaryduring the wintertime surge."

WATCH| Children hit hard by COVID-19 surge in U.S.:

Children hit hard by COVID-19 surge in U.S.

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The latest surge of COVID-19 cases in the U.S. is mostly in the unvaccinated, especially children who arent eligible. With school about to begin, there is debate about how to protect them.

One reason for thatisthe dominance of the delta variant, which Kimberlinestimates is about 90 per cent of the COVID-19 cases he's seeing now.

The other big reason, he said, is "abysmal vaccination rates"in COVID hotspots.

"You put a highly, even much more infectioushyper-infectious, hyper-transmissible virus that this delta variant represents into a population that'sa third vaccinated, you got a recipe for disaster," said Kimberlin.

"We're living that disaster right now."

Data from the Centers for Disease Control and Prevention showa 27.3 per cent risein the seven-day average for U.S. COVID-19 hospital admissions among children from 0 to 17 years old between the week of July 28 to Aug. 3 and the week of Aug. 4 to Aug. 10.

According to additional CDC data, the highest COVID-19 case rates per 100,000 people are in Alabama, Arkansas, Louisiana, Mississippi and Florida.

What's happening with kids and COVID-19 in Canada?

Right now, experts say Canada isn'tseeingthe surge of pediatric cases and hospitalizations that the southern U.S. is experiencing.That includes at one of the country's largest children's hospitals.

"SickKidshas not seen any increases in COVID-19 hospitalizations or disease severity due to the delta variant," a spokesperson for the Toronto hospital said in an email to CBC News."Throughout the pandemic, we have monitored COVID-19 trends in other jurisdictions and we continue to do so closely."

One of the reasons it hasn't happened, experts say, is Canada's much higher vaccination rate. According to CBC's vaccine tracker, 71 per cent of the eligiblepopulation currently anyone 12 years and older hasbeen fully vaccinated in Canada.

"Vaccination in Canada seems to be less of a political issue and more of a health-related issueand we are lucky for that," said Dr. Jeff Pernica, an infectious disease specialist at McMaster University in Hamilton.

"We know that two doses of the available mRNAvaccines provides very good protection even against delta," he said. "And so I do not necessarily think that what's happening inthe United States is going to happen here."

Does the delta variant make people sicker than other forms of the virus?

The short answer is that experts don't yet know for sure.

"We know that everybody is more susceptible to the delta variant," saidDr. Laura Sauv, chair of the Canadian Paediatric Society's infectious diseases committee and an infectious disease specialist at B.C. Children's Hospital.

"It's just much more transmissible thanprevious strains of COVID-19."

But the question of delta's "virulence" meaning whether the illness it causes is more severe is still not clear.

Several infectious disease specialists say that although there are more pediatric hospitalizations than before in the U.S., that could be due to the fact that delta causes more infections overall. So the same percentage of patientsas before could be suffering from serious illness, but there's a largertotal pool of infected children and teens.

Aren't kids under 12 at particular risk since they can't get vaccinated?

Yes, experts say but there are still things we can do to protect them.

The current fourth wave of COVID-19, including the delta variant,is largelyinfecting people who are unvaccinated, said Dr. Anna Banerji, a pediatric infectious disease specialist at the University of Toronto's Dalla Lana School of Public Health.

"Our main unvaccinated population right now in Canada is mostly the kids [who are]less than 12. So that's a big concern to me," shesaid.

Both Pfizer-BioNTech and Modernaare currently doing clinical trials to determine whether their vaccines are safe and effective for children under 12.Banerji is hoping results will be available in the coming months.

In the meantime,experts say one of the most important things peoplecan do to protect kids from the delta variant is to get vaccinated themselves.

"Having the adults around them protected by vaccination will help protect kids who are too young to be vaccinated," saidSauv.

"That includeskids over 12so high school students, middle school students.But also parents and teachers, and other health-care workers and other education workers."

In addition,Sauvsaid, it's critical to keep up other public health measures, such as wearing masks indoors, especially where community transmission is high.

Many people dropped those public health measures in the areas of the U.S. now being hard-hit, said Kimberlin.

"[We've] ...got to go back to the same kinds of things we don't like and that's wearing masks and trying to distance from one another and doing the kinds of things that we were so familiar with in the wintertime and last year," he said.

Is it still true that kids usually don't get as sick if they get COVID?

Yes, infectious disease specialists say.There's nothing to suggest the delta variant has changed that.

"Of all kids who get COVID, probably the majority will haveno symptoms at all," said Sauv.

"Another significant proportion will have, kind of, mild flu-like symptoms. Like they might feel crummy for a few days, they might have some fever, they might have some cough, andin most cases, thatgoes away fairly quickly.

"A very, very small proportion of kids with COVIDdo get sick enough with COVID to be admitted to hospital. But that's a very tiny proportion."

Should Canadian kids return to school this fall?

All of the Canadian infectious disease and public health expertsCBC News interviewed gave a resounding "yes."

"It's really important that we do everything we can to get kids back in school in person," saidSauv.

"The mental health and developmental effects of COVIDhave been the most profound effects of COVIDon children, and we're seeing significant increases in mental health hospitalizations," she said.

Dr. Lawrence Loh, the medical officer of health forOntario's Peel region, agreed that a return to school is vitalfor kids with COVID-19 safety precautions in place.

"In general, schools reflect the community transmission that's occurring," Loh said. "And we know that one of the best ways to address community transmission is to make sure that everyone is getting vaccinated as much as possible.

"The additional measures that are in place in schoolscohorting, screening, dismissals, maskingthose are all going to still be critical."