Health Canada approved Moderna’s COVID-19 vaccine for kids under five on Thursday, making infants, toddlers and preschoolers eligible for vaccination for the first time.

Here is what you need to know:

When will it arrive and how will it be administered?

An Ontario government spokesperson told CP24 that the province expects to receive the Moderna vaccine for kids under five “late” in the week of July 18-22, with administration beginning soon after.

Moderna and the U.S. Food and Drug Administration say the doses should be administered about one month apart, but NACI and Health Canada say they should be administered eight weeks apart, to maximize the generation of neutralizing antibodies over a wider period of time.

During the rollout of the Pfizer pediatric vaccine last winter, parents in Ontario could opt to have their child receive their second dose in a shorter than eight week timeframe.

It is not known if that option will be available for this younger cohort.

The 10 microgram shot goes into the deltoid like most other vaccines.

It’s smaller than the 25 microgram Pfizer pediatric dose given to 5-11 year-olds and 50 microgram Moderna dose approved for older children.

In comparison, adults receive either a 100 microgram dose of Moderna or 30 micrograms of a Pfizer dose.

Why it is needed

Pediatric infectious diseases specialist Anna Banerji told CP24 that COVID-19, especially Omicron, can cause very severe outcomes in small children.

“There can be COVID pneumonia, COVID can exacerbate other underlying conditions like asthma, you can have serious issues like inflammatory syndrome,” she said.

In fact, Public Health Ontario’s tracking of hospitalizations due to COVID-19 finds that during the length of the pandemic, kids up to four years-old have been hospitalized at five to six times the rate of children aged 5-11 and 12 to 19, with a particularly wide disparity after the arrival of the Omicron variant.

She said that the estimated timeline suggests no small child will be fully vaccinated by the start of September, but there is an opportunity to get first doses to a large portion of them before then.

“It’s two doses of the vaccine eight weeks apart, so I am not sure we can get the kids vaccinated before school starts. But we can start as soon it’s available.”

She said giving the daycare and preschool and even some junior kindergarteners vaccines against COVID-19 will lower the incidence of transmission and severe outcomes when the summer ends.

“It’s the last grouping of unvaccinated people who are together in these settings so it’s a really big deal.”

NACI found the Moderna pediatric vaccine to be 51 per cent effective at preventing symptomatic infection starting two weeks after dose two, in a trial conducted when Omicron was the dominant strain circulating in Canada.

There were no deaths or severe outcomes among the vaccinated group of trial participants due to COVID-19 or related conditions like Multi-System Inflammatory Syndrome in Children (MIS-C).

Is it safe?

Banerji said the Canadian trials found side-effects typical to all vaccines, but nothing serious.

“In the study they had a placebo groups and they had vaccinated groups – they had 5,500 kids in the study. There were no serious side effects to the vaccine, there was irritability, crying but no serious side-effects associated with the vaccine.”

“There’s been generally no side effects in the groups of older kids. There has been myocarditis in certain age groups but generally the vaccine is safe.”

Will it reduce incidences of Long-COVID?

The shot will likely reduce the incidence of persistent COVID-19 symptoms in small children, as it has in adults around the world.

A review this year by the UK Health Security Agency found fully vaccinated people were about half as likely to see long-COVID symptoms compared with unvaccinated or partially vaccinated people.