Vaccine Cold Chain
The vaccine cold chain is simply the system of transporting and storing vaccines between the point of manufacture and final use.
To maximise the shelf life of a vaccine it is important to keep it at a suitable temperature. The range 2° (not -2°) is the agreed lower limit and 8° is the agreed upper limit. Of the two, the lower limit is more important. It is essential that a vaccine is NEVER STORED BELOW 0°C. When a vaccine is frozen it loses its efficacy.
Vaccines are also sensitive to heat and UV light, including fluorescent light. Vaccines have varying degrees of heat stability and sensitivity to freezing. Repeated exposure to temperatures outside the +2°C to +8°C range diminishes vaccine potency. This effect is cumulative and cannot be reversed.
What is a cold chain breach?
A cold chain breach is when the vaccine temperature reaches more than 8°C for 15 minutes, or below 2° (for any amount of time). All breaches should be reported to your state or territory health department along with the temperature log. This will assist in determining if the vaccine needs to be disposed of, or can still be used, potentially with a revised use-by date.
Why is this important?
Exposure to heat or freezing has a cumulative effect on vaccine viability. By distributing a vaccine with a compromised efficacy, the practitioner is potentially putting the health of patient at risk, as well as the wider community.