The Importance of Cold Chain

Vaccines are sensitive biological substances that can
lose their potency and effectiveness if they are exposed
to heat and/or direct sunlight or fluorescent light. For
example, certain vaccines lose potency when exposed
to room temperature for as little as 30 minutes,
or when exposed to light. Freezing damages most
vaccines. Exposed vaccines can result in a reduced
immune response and/or increased local reactions.
The loss of vaccine potency cannot be reversed.
Protecting Ontario’s
Vaccine Supply
The Mandatory Health Programs and Services
Guidelines, issued under the Health Protection and
Promotion Act, require local public health units to
inspect premises where provincially funded vaccine
is stored, at least once annually. Recent inspections
of refrigerators in physicians’ offices and other
health care facilities have shown that improper
storage and handling of vaccines is still a significant
problem in Ontario.
Vaccines may be wasted if they have been exposed
to temperatures below +2°C or above +8°C, and are
spoiled, or if they have expired before they can be
used. Vaccine wastage results in increased costs
(to replace the wasted vaccines). Also, with the
globalization of the vaccine manufacturing industry,
and intermittent global vaccine shortages, it is not
always possible for Ontario to quickly obtain additional
quantities of vaccines to replace vaccine that is wasted.
Patients/clients who are immunized with exposed
vaccines often need to be recalled by the health
care practitioner and reimmmunized to ensure
that they are protected against the specific vaccine
preventable disease(s).