MONTREAL (AFP) - Pfizer-BioNTech submitted an authorisation request to Health Canada on Monday (Oct 18) for the use of its Covid-19 vaccine in children aged five to 11, the companies and the Canadian government said.

"This is the first submission Health Canada has received for the use of a Covid-19 vaccine in this younger age group," it said in a statement.

The authorisation request is based on data from trials conducted on 2,268 children in this age group for whom the dosage was lowered to 10 micrograms per injection - three times less than the standard dose - which the company says is "the preferred dose" for five- to 11-year-olds.

This same Pfizer-BioNTech vaccine is approved in Canada for those aged 12 and up.

Health Canada said that it will authorise the use of the vaccine only if the independent and thorough scientific review of all data submitted confirms that the benefits outweigh the risks with this group.

The Canadian ministry indicated that other manufacturers also were testing their vaccines on children of different age groups.

Earlier this month, Pfizer-BioNTech made the same request for five- to 11-year-olds in the United States.

Childhood immunisations are raising questions around the world. Many countries vaccinate adolescents from the age of 12, but very few do so for those below that age.

In recent months, the World Health Organisation has insisted that the urgent issue is to immunise the population of poor countries before children and adolescents in rich countries.