Administration of Influenza Vaccine

Advisory Alert

December 2, 2019

To community health care providers:

Re: Administration of Influenza Vaccine

Below is a communication from the Chief Medical Officer of Health regarding the administration of influenza vaccine.

Needle Gauge and Length for Intramuscular Injections

For intramuscular injections (IM), using the appropriate needle is important to ensure the immunizing agent reaches the appropriate tissue site to optimize the immune response.

Vaccine recipientRecommended needle gaugeRecommended needle length
Infants, toddlers and older children22-25⅞ inch – 1 inch
Adolescents and adults22-251 inch - 1½ inch

For further information see Table 1: Vaccine Administration in the Publicly Funded Immunization Schedules for Ontario, available at

Influenza Vaccine Dose

The recommended influenza vaccine dosage for individuals 6 months of age and older is 0.5mL.

Safety Engineered Needles

The Needle Safety Regulation, under the Occupational Health and Safety Act, which requires the use of safety engineered needles, applies to all workplaces where health related services are provided. The use of safety engineered needles reduce the risk of a skin puncture or injury to the worker.

Additional information regarding the Universal Influenza Immunization Program can be found at

Should you have any questions, please contact the immunization program at 705.522.9200, ext. 301.


Ariella Zbar, MD, CCFP, MPH, MBA, FRCPC
Associate Medical Officer of Health and Director, Clinical Services

Administration of Influenza Vaccine, Chief Medical Officer of Health


Administration of Influenza Vaccine CMOH Letter to HCP (PDF, 148 KB)


Administration of Influenza Vaccine CMOH Letter to HCP (PDF, 148 KB)



This item was last modified on December 2, 2019