Access to the seasonal flu vaccine in Canada -
How the flu shot makes its way from the laboratory to the doctor's office.
Health Canada
2007
HC PUB.: 5838
Cat: H164-47/2007 (print publication)
ISBN: 978-0-662-69932-3 (print publication)
Help on accessing alternative formats, such as PDF, MP3 and WAV files, can be obtained in the alternate format help section.
 (368K)
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How the flu shot makes its way from the laboratory to the doctor’s office
Step 1: Identifying the Virus
Step 2: Constructing the Strain and Reagents
Step 3: Production of Flu Vaccine
Step 4: Market Authorization
Step 5: Supply and Distribution of Flu Vaccine in Canada
Step 6: Post-Market Surveillance
Conclusion
How the flu shot makes its way from
the laboratory to the doctor's office.
Every year, millions of Canadians are affected by the
flu (influenza), a respiratory illness caused by a virus.
Those who get the flu have high fever, chills,
sweating, headache, sore throat, dry cough, muscle
aches, extreme tiredness and weakness. Those who
are particularly vulnerable to the flu and its effects
are the very young, the elderly, and those with a
weakened immune system.
The flu can cause a range of problems from a few
sick days, to hospitalization and even death.
Therefore the seasonal flu vaccine is an important
protective resource that Canadians have access to
every year, in time for the flu season. |
The following publication describes
the pathway for the development,
regulation and distribution of the flu
vaccine in Canada.
Step 1: Identifying the Virus
The flu virus strains circulating the globe change on a
regular basis. Therefore the process for flu vaccine
development starts off on a global scale annually.
Each year in February, the World Health Organization
(WHO) selects three influenza virus isolates which form
the basis for flu vaccine production for the following fall
and winter flu season.
Step 2: Constructing the
Strain and Reagents
In general, vaccines are produced by isolating or
creating an organism (or part of one) that retains
specific proteins called antigens which are
responsible for inducing the body's immune response.
WHO collaborating centres oversee the construction
of vaccine strains from the three selected influenza
virus isolates. These organizations also produce
special reagents to monitor the quality of vaccine
production.
The vaccine strains and reagents are then
distributed to flu vaccine manufacturers.
Step 3: Production of
Flu Vaccine
There are a handful of flu vaccine manufacturers
responsible for running the production process and
distributing the vaccine across North America and Europe.
Vaccines are Biologics:
Vaccines differ from other drugs because of their biological (and
hence, variable) nature, the raw materials used in their production
and the biological methods used to test them. Special procedures
are needed for their manufacture, control and regulation. |
The current manufacturing process involves the
replication of vaccine strains in eggs. A few
manufacturers use animal cells instead.
Clinical trials (studies) are conducted on humans to
ensure that the vaccine is safe and effective.
Once the manufacturer has acquired sufficient
scientific evidence that the vaccine is safe, effective
and of suitable quality, a submission may be filed
with Health Canada for market approval.
The Future of Vaccine Manufacturing:
New methods using modern molecular techniques (e.g.
recombinant protein and plant based technology) are under
development to improve the ability to duplicate protective
properties of the vaccine strain. Such techniques may have the
potential to expand manufacturing capacity to produce larger flu
vaccine supply in a shorter timeframe. |
Step 4: Market
Authorization
The Biologics and Genetic Therapies Directorate
(BGTD) is the federal program within Health Canada's
Health Products and Food Branch that is responsible
for the regulation of new biological drugs, including
vaccines.
Although they have an excellent safety record, vaccines
are strictly regulated because they are unique in the
fact that they are commonly administered to very large
numbers of healthy people, including infants and
children, in national immunization programs. Safety
and quality are critical elements overseen by the BGTD.
Prior to market approval of a new vaccine, the manufacturer must file a New Drug Submission that demonstrates the safety, efficacy and quality of the flu vaccine to the BGTD. Vaccine manufacturers must supply facility information that outlines the method of manufacture in significant detail. An On-Site Evaluation is performed by BGTD scientists to assess the production process and the facility. Samples of at least three consecutive batches or "lots" of the vaccine are also tested in the laboratories of the BGTD to ensure consistency in the manufacturing process.
Results from human clinical trials must also be
submitted, which provide evidence of the safety and
efficacy profile of the product.
If, after the completion of the review, it is concluded
that the benefits of the vaccine outweigh its risks, then
the vaccine is issued a Notice of Compliance (NOC) and
a Drug Identification Number (DIN), indicating that it is
authorized for sale in Canada.
Following the issuance of an NOC, the manufacturer is
required to submit samples of each lot to the BGTD for
lot release testing. After confirming the safety and
potency of each vaccine lot in its own laboratories, the
BGTD issues a lot release letter authorizing the
manufacturer to sell it in Canada.
Since the flu vaccine changes every year,
manufacturers must send updated information on their
manufacturing process with the selected strains as
well as data from small clinical trials to demonstrate
that the vaccine produced is able to stimulate the
immune system of vaccinated individuals. The BGTD
conducts an expedited review of the data and
authorizes these modifications. This period typically
occurs between July and September each year.
Step 5: Supply and
Distribution of Flu
Vaccine in Canada
The Government of Canada, through Public Works
and Government Services Canada (PWGSC),
purchases flu vaccines on behalf of the provinces and
territories. Long-term contracts are established with
manufacturers and estimated requirements are
provided several months in advance of the flu season,
to secure adequate supply. The vaccine is available
at public health clinics and doctor's offices in
accordance with provincial and territorial influenza
immunization programs. Flu vaccines are also
available through private market contracts - and can
be found at local pharmacies for those individuals
seeking to buy them.
The Public Health Agency of Canada (PHAC) assists
in the coordination and oversight of public market
supply and distribution, in collaboration with PWGSC,
BGTD (Health Canada), the manufacturers and
Federal/Provincial/Territorial (FPT) committees.
FPT Committees include the Canadian Immunization
Committee that advises on immunization program
planning and the Vaccine Supply Working Group that
advises on vaccine supply issues across Canada.
The National Advisory Committee on Immunization
(NACI) is an expert committee reporting to Canada's
Chief Public Health Officer. NACI makes annual
recommendations for the use of influenza vaccines in
Canada including the identification of groups at risk of
influenza for whom vaccine programs should be targeted.
Step 6: Post-Market
Surveillance
PHAC carries out post-market surveillance of the flu vaccine, through the Canadian Adverse Events Following Immunization Surveillance System (CAEFISS). The CAEFISS includes a voluntary reporting system where local, provincial and territorial public health and health care providers can report adverse events they feel are associated with an immunization. Additionally there is an active paediatric hospital based surveillance network (Immunization Monitoring Program Active, or "IMPACT") that identifies selected serious adverse events that follow immunization.
Manufacturers are required to report to the BGTD all
serious vaccination failures.
For more information on post-market surveillance for the flu vaccine, refer to the following  website.
Conclusion
Step 1: Identifying the Virus
Step 2: Constructing the Strain and Reagents
Step 3: Production of Flu Vaccine
Step 4: Market Authorization
Step 5: Supply and Distribution of Flu Vaccine in Canada
Step 6: Post-Market Surveillance
As the flu vaccine changes each year, all aspects of
the flu vaccine, from strain identification, to production,
regulatory authorization and distribution must be
achieved within a time period of less than 8 months.
As such significant international and national
cooperation is required before the start of the flu shot
campaign in November of each year.
The flu vaccine is a national resource that saves lives,
can offset public health crises and contribute to quality
of life in Canada.
Despite the promising advancements made in recent
years, progress continues towards improving the
manufacturing process, timeliness, availability and
awareness of the flu vaccine. Health Canada plays a
key role in ensuring that Canadians have access to
safe and effective flu vaccines, through regulation.
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