A recent study suggests that the majority of farm fridges may not maintain temperatures within the 2–8^oC range recommended for the storage of most vaccines. In the study, which was supported by MSD and led by Rosie Lyle of Bishopton Veterinary Group, 18 farmers placed temperature loggers in the fridge where they normally store vaccines. Temperatures were then monitored between February and April. Throughout this period, 89% of loggers recorded a temperature outside the 2–8^oC range at least once, and 43% recorded temperatures outside this range more than 50% of the time. These findings raise potential concerns about vaccine efficacy.

On analysing the results, Rosie Lyle found that 55% of the loggers recorded a temperature over 8^oC, and 39% recorded a temperature below 2^oC. Across all the fridges monitored, the maximum temperature recorded was 12^oC and the minimum was -11.5^oC. “This is a surprisingly wide range,” says Rosie. “Obviously, these findings are concerning for farmers as we know that both too high and too low temperatures can impair vaccine efficacy.” Live vaccines tend to be particularly sensitive to elevated temperatures, she explains, whereas inactivated vaccines are more affected by freezing, especially when the adjuvant contains aluminium salts.

Rosie Lyle, Bishopton Veterinary Group

Rosie shares the implications of her study. “It’s important for both farmers and vets to be aware of potential concerns about vaccine efficacy, given the possible impact on herd health and the potential for vaccine failure to reduce trust in vaccines and herd health recommendations,” she says.

In light of Rosie’s findings, vets across the XLVets community are encouraging farmers to take action to improve medicine storage. Such actions include using max/min thermometers or temperature loggers to track fridge temperature, as well as taking steps to maximise the efficiency of each fridge. Ensuring that fridges are not subjected to wide variations in external temperature, as well as enabling adequate airflow and stopping dirt from building up in the grills, are simple interventions that can make a big difference. Vets from XLVets practices also deliver FarmSkills courses which address medicine storage and are available to any farmer in the UK here.

Susan Goodfellow, Marketing Manager at XLVets, emphasises the value of projects such as this conducted within the XLVets community. “We wouldn’t have known that this is an important issue to highlight to farmers without collecting the information, so Rosie’s study was very valuable,” she says. “In the XLVets community, we support clinical leadership with these kind of projects – we actively collect data and make sure that farmers can benefit from the latest findings. As a group of independent practices working together, we can achieve much more than we could in isolation.” To find out more about the XLVets community, visit: https://www.xlvets.co.uk/the-boss/