The Middlesex-London Health Unit (MLHU) says this is due to the challenges associated with a delayed delivery of Pfizer next week.
The vaccination clinics at the Western Fair Agriplex, North London Optimist Community Centre and the Caradoc Community Centre in Mount Brydges will administer Moderna to adults for first or second doses.
A limited supply of Pfizer will be available at each clinic for youth aged 12 to 17 years old.
The vaccination clinic at Earl Nichols Arena remains Pfizer-only, according to the MLHU.
The MLHU says the interchangeability of mRNA vaccines has been supported by experts at both the Public Health Agency of Canada and the National Advisory Committee on Immunization.
“Regardless of which vaccine you received for your first dose, Moderna is an excellent vaccine for your second dose,” Dr. Chris Mackie, Medical Officer of Health at the MLHU, said.
“Pfizer and Moderna are essentially different brands of the same vaccine, and you will have the same protection against COVID-19 regardless of what you get for your first or second dose,” he continued.
Those looking to book a vaccine appointment can do so online or by calling 226-289-3560 (8:00 a.m. to 7:30 p.m., Monday to Sunday).