September 25, 2009: Update on influenza vaccinesMemoTo: Primary Care Providers Dr. Arlene King, Ontario's Chief Medical Officer of Health, announced yesterday afternoon the province's recommended rollout and sequencing strategy for this year's flu shots. First, the seasonal flu shot will be offered to seniors and residents of long-term care facilities, then the pH1N1 vaccine will be offered to all Ontarians in the recommended sequence, and finally the seasonal flu shot will be offered to the general population. Please note that these recommendations are aligned with tailoring protective measures to the different segments of the population. We are anticipating that pH1N1 will be the predominant strain this flu season, but as seen in the southern hemisphere it will not be the only strain circulating. While unpublished research studies (which Ottawa Public Health has not seen) show a possible association between prior immunization with the seasonal flu vaccine and infection with pH1N1, the study information is not the only rationale for the change in the rollout strategy. Attached is a document released on September 24 by the Ministry of Health and Long-Term Care about Ontario’s flu vaccination strategy. A nine-page question and answer document has also been released to health units to assist with media requests. Ottawa Public Health can forward this to you electronically upon your request to heathsante@ottawa.ca. As well, Ottawa Public Health is posting a Frequently Asked Questions document on pH1N1 vaccine safety at ottawa.ca/health that you can refer your patients to. As always, your patients are welcome to call Ottawa Public Health Information Line at 613-580-6744 for individual consultation. If you have any questions or wish to request resources, please contact us via phone at 613-580-6744. BACKGROUNDER![]() Ministry of Health and Long-Term Care Ontario will immunize people 65 years of age and older and residents of long-term care homes, with seasonal flu vaccine first. Ontario will offer the rest of the province’s population the H1N1 vaccine beginning in November followed by a universal influenza immunization program with the seasonal flu vaccine in the months following. Ontario’s decision to take this approach is based on scientific analysis by the province’s top immunization experts suggesting that this vaccination sequence strategy will provide the greatest benefit to the population’s health. Vaccine DeliveryOntario is adopting a phased approach in rolling out two flu immunization programs this year. There will be enough H1N1 and seasonal flu vaccine for all Ontarians who need and want to be vaccinated.
Circulating Flu StrainsBased on experience in the southern hemisphere where the pandemic H1N1 flu virus has been dominant, we are anticipating a possible re-emergence of the H1N1 virus in Canada this fall, followed by the circulation of seasonal influenza strains later in the season. Public health officials anticipate that the pandemic H1N1 flu virus will be the predominant strain circulating this fall. Broad flu vaccination in Ontario will be sharply focused on the H1N1 vaccine. Flu Vaccine SequencingEpidemiological studies show that seniors are most at risk of serious complications, hospitalization and even death from infection with seasonal flu. On the other hand, data shows that infection from the pandemic H1N1 virus does not typically occur in persons over age 60, probably as a result of residual immunity from exposure to H1N1 prior to 1957. Other population groups are encouraged to delay immunization with seasonal vaccine because some Canadian studies suggest a potential association between prior seasonal influenza vaccination and the risk of acquiring infection with H1N1 flu. Although these studies are still undergoing further analysis, we want to take a position of precaution. Ontarians who are neither over 65 years old nor residing in long-term care homes are encouraged to get immunized against the H1N1 flu virus first, followed by seasonal flu vaccination. For public inquiries call ServiceOntario, INFOline at 1-866-532-3161 (Toll-free in Ontario only) Media Contacts: Neala Barton, Minister’s Office, 416-327-4320 |

