EDMONTON -- The National Advisory Committee on Immunization (NACI) says receiving a second dose of an mRNA vaccine is recommended – an approach Alberta has been taking for several weeks.

Alberta Health spokesperson Tom McMillan says the vast majority of Albertans who have received AstraZeneca as a first dose have opted for a second dose of an mRNA shot, such as Pfizer-BioNTech and Moderna.

NACI said those who received AstraZeneca as a first dose can choose between a second dose of AstraZeneca or an mRNA vaccine.

“Both vaccines are good and will help protect you against COVID-19. The choice is up to each Albertan, but there is emerging evidence that mixing doses can produce an even stronger immune response,” said McMillan.

There have been approximately 278,000 doses of AstraZeneca administered in Alberta, McMillan said. This includes approximately 256,800 first doses and 21,200 second doses.

There are currently 22,000 unused AstraZeneca vaccines in Alberta, McMillan added.

“The best choice you can make is to get fully vaccinated as soon as you can."