An increase to the shelf-life of the Pfizer Covid-19 vaccine is allowing Tayside and Fife to put on more drop-in clinics and get extra people vaccinated.
The Pfizer/BioNTech needed to be stored in expensive ultra-cold freezers until five days before being administered.
But regulators recently decided it can now be kept at fridge temperature for up to a month after thawing giving vaccination teams a “bigger window”.
Covid-19 vaccines ‘tightly controlled’
NHS Fife chief pharmacist, Ben Hannan, said the changes have provided flexibility at a time when most first doses must be Pfizer or Moderna as per safety guidance for younger age groups.
He said: “The storage and transportation of Covid-19 vaccines is tightly controlled, however, the extension of the vaccine shelf life has allowed us to be more flexible in our delivery of the vaccination programme.
“Throughout the programme, measures have been in place to ensure there is minimal wastage, however, the change in storage requirements gives us a bigger window to manage stock, and perhaps more importantly gives us greater flexibility to provide drop-in vaccination clinics, as we have done over recent weeks.
“Our drop-in clinics continue to operate across Fife and are open to anyone over the age of 18 requiring a first dose, or those requiring a second dose who received their first more than eight weeks ago.
Pfizer temperature colder than Antarctic winter
The UK regulator says Pfizer — the first vaccine to be approved in the UK in December 2020 — has to be “deep frozen” at between -60C and -80C.
The temperature range — colder than the Antarctic winter — is a big financial and logistical challenge.
But after a change in May this year, the mRNA jag no longer needs to be administered within 5 days of being removed from freezers.
It can instead keep for up to 31 days at 2°C to 8°C.
Once it has been opened and mixed with saline, it can be stored or transported at room temperatures for up to six hours.
NHS Tayside also say the Pfizer vaccine is now much easier to distribute.
A spokesperson said: “The extension of the shelf life for the Pfizer vaccine has helped our vaccination teams to manage stock locally at clinics by offering flexibility and reducing the need to move vaccine between clinics.
“The teams at our clinics have managed vaccines extremely well throughout the programme and vaccine wastage remains very low across Tayside.”
There are drop-in clinics across Tayside this weekend, including in Dundee, Perth, Blairgowrie, Forfar, Arbroath, Montrose, and at Stracathro near Brechin.
What about the other vaccines?
The AstraZeneca vaccine is much easier to distribute as it’s safe to store at between 2ºC to 8ºC for six months.
After first opening the vial, it should be used within six hours and stored between 2˚C and 25˚C during this period.
Moderna vials are slightly more tricky because they should be stored frozen between -25º to -15ºC and have a shelf-life of seven months at these temperatures.
Once thawed, the vaccine may be stored at 2°C to 8°C and protected from light for up to 30 days if not punctured.
The unopened vial is stable for 12 hours at 8° to 25°C.