Guidance on H1N1 Flu Vaccine Sequencing

Preamble

It is recognized that some individuals or groups not identified below may be at higher risk of severe illness or hospitalization due to socio-economic and lifestyle conditions, access to health care, and elevated risk of exposure to the H1N1 flu virus. Consideration will be given to targeting these individuals for immunization as our understanding of the virus evolves. Further consideration could be given to immunizing additional groups or individuals if needed to minimize societal disruption.

Recognizing that many Aboriginal populations are younger; may be more socio-economically disadvantaged compared to Canadians as a whole; have higher numbers of pregnant women; have higher rates of diagnosed and possibly un-diagnosed chronic disease; and may live in remote and isolated communities, all efforts will be made to enable those Aboriginal people who would benefit most from immunization, wherever they reside, to have access to H1N1 flu vaccine as soon as possible.

1. Those Who Will Benefit Most From Immunization and Those Who Care For Them

Persons with chronic conditions (NACI list) under the age of 65

Rationale: at higher risk of complications; 65+ less affected to date, Canadian modeling suggests immunizing this group decreases population morbidity and mortality more than immunizing children (i.e. groups with highest attack rate)

Pregnant women 

Rationale: at highest risk of severe disease, and to potentially protect their infants¹

Children 6 months to less than 5 years of age

Rationale: Children 6-23 months of age are at particular risk of severe disease and hospitalisation and are the primary focus of this group. Children aged 2 years to less than 5 years of age were included within this group because:

• they are at higher risk of severe disease and hospitalisation than older children,  and
• from a targeting perspective for operationalizing vaccine delivery the single category of 6 months to less than 5 years effectively captures all "pre-school" aged children.
• Note that vaccine may not be authorised for use in children less than 6 months of age

Persons residing in remote and isolated settings or communities

Rationale: limited access to medical care, potential for development of mass immunity and prevention of infection, logistically easier to target whole community; equity, high concentration of persons with chronic conditions, observed morbidity/mortality in some remote Aboriginal communities

Health care workers HCW (all health care system workers involved with the pandemic response or delivery of essential health services*)

Rationale: prevent HCW spread to vulnerable patients, prevent outbreaks, protect HCW (reciprocity) and protect essential health infrastructure

All health care workers involved with the pandemic response or delivery of essential health services:

• Those who provide direct patient care as well as those who support the provision of health care services
• Includes full-time staff, part-time staff, students, regular visitors and volunteers i.e. all persons carrying out the health care function
• Settings include acute care, chronic care, ambulatory/community care, emergency medical services, laboratory, public health departments, pharmacies etc.
• Includes Canadian Blood Services/Héma Québec and vaccine manufacturers

Household contacts and care providers of:

• Infants <6 months of age
• Persons who are immunocompromised

Rationale: indirect protection for persons at high risk who cannot be immunized or may not respond to vaccine

Populations otherwise identified as high risk

2. Others Who Will Benefit From Immunization

Children 5 to 18 (inclusive) years of age

Rationale: high attack rates experienced by this age bracket would suggest they be considered a priority within this phase of immunization to possibly reduce transmission of the virus, children identified as a priority in public consultations

First responders (police, firefighters)

Rationale: frequently attend emergency health situations with Emergency Medical Services (EMS)

Poultry and Swine Workers

Rationale: to prevent opportunities for viral reassortment

Adults 19 to 64 (inclusive) years of age

Rationale: increased risk of severe H1N1 disease

Adults 65 years of age and over

Rationale: low attack rates, potential for reduced response to vaccine

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¹ This is a WHO definition refers to the maternal antibodies transferred to the fetus in utero protecting the infant after birth as well as to include the post-partum period.