Healthcare workers carrying vaccines on a motorbike to remote communities, Nigeria

Vaccines - coming in from the cold

‘Thermostability’ - it may sound very technical and complicated, but really it’s all about fridges.

The term just means ‘how well something remains unchanged as the temperature varies’. Many vaccines are not very thermostable, so they need to be kept at a constant temperature to be effective. In most cases, this means ‘cold’.

All the way through the process of manufacturing, to packaging and shipping, vaccines need to stay within this specific temperature range to ensure that they are fit for purpose when they reach their final destination – the patient.

Achieving this relies on what’s known as the cold-chain – referred to by many as the biggest challenge in getting vaccines out to people around the world.

The start of the chain

Our vaccines begin their cold chain in manufacturing plants, then are sent to the airport, destined for a refrigerated unit on a plane. So far so good. But the challenges can really start as soon as the plane touches down. A typical journey in some countries - such as Tanzania for instance - might involve being transferred to a cool box and taken by sailboat to a small group of islands with no electricity, or taken by donkey to collections of small villages in the mountains – all in searing heat. From start to finish, the vaccines may have been travelling for many hours, and perhaps even days.

Our vaccines begin their cold chain in manufacturing plants, But the challenges can really start as soon as the plane touches down.

Most of our vaccines need to be stored between +2°C and +8°C. If the temperature strays beyond this range anywhere along the supply chain after the vaccine leaves our control, the local healthcare provider receiving the doses may need to dispose of the vaccines. Too many vaccines are reported discarded for this reason every year, instead of making it to the children who need them.

So to reduce this waste, and in an effort to make the distribution process easier in remote areas, we’ve joined forces with the Bill & Melinda Gates Foundation to form a new Vaccine Discovery Partnership. The Partnership will look at whether we can make some of our vaccines more resistant to heat. If we can do this, then some vaccines may be able to remain outside refrigeration for short periods of time.

Towards better decision making

This could ultimately help everyone involved in the distribution chain make more informed decisions, stop unnecessary waste and ensure that more people can receive the vaccines that could protect them against a range of diseases.

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The world’s first candidate vaccine for malaria

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