Vaccines are delicate things. They have a very short shelf life once opened or reconstituted, and they must be kept, during both storage and transport, at a cool 2-8°C. Going outside this range could mean the vaccine loses its potency and efficacy.
A study conducted on 20 farms in the south-west of England between January and August 2014 placed temperature data loggers inside fridges used to store vaccines on farm*. Fridge temperatures were logged every 30 minutes.
All the farm fridges in the study failed to maintain an internal temperature of 2-8°C at some point during the study and, as such, were inadequate to provide proper vaccine storage – specifically:
- 59%of farm fridges had at least one temperature recording above 8°C
- 53% had at least one recording below 2°C
- 41% had at least one recording at or below 0°C
- The highest internal fridge temperature recorded was 24°C and the lowest -12°C
- Fridges tested spent an average of 16%of the total time recorded above 8°C
- Time of the year significantly influenced the percentage of time above 8°C, with internal fridge temperatures more likely to be warmer between May and August
We monitor the Scarsdale fridge temperatures on a twice-daily basis. Why not invest in a fridge thermometer and do the same on farm? It might make all the difference between your vaccines being effective or being useless!
N.B. A small-scale, informal study conducted among local farmers by Sid a few years ago found that many of the farm fridges used to store vaccine were rejects from the farm kitchen. If it’s not good enough for your beer, it’s not good enough for your vaccine!
*Williams, P. D. and Paixão, G. (2018) On-farm storage of livestock vaccines may be a risk to vaccine efficacy: a study of the performance of on-farm refrigerators to maintain the correct storage temperature. BMC Veterinary Research 14:136.