Fridge-free vaccines could reach more people, but there are still practical challenges in African settings

Keeping vaccines and medicines at the right temperature is critical for their efficacy and safety.

But this is an often overlooked part of getting them to the people who need them.

In April 2025 , the UK biotechnology company Stablepharma began the first human trial of a tetanus-diphtheria vaccine designed to remain stable without refrigeration.

The development has renewed interest in technologies that could do the job, particularly in places where electricity, transport, and storage infrastructure are limited.

We spoke to immunisation experts Charles Shey Wiysonge and Chinwe Juliana Iwu-Jaja about this.

Why is vaccine storage such a big issue? Vaccines take a long journey before reaching the person they are meant to protect.

Some vaccines can be in transit and storage for several months: from the manufacturer to refrigerated vehicles, national cold rooms, district cold rooms, health facility fridges, and outreach sessions.

Vaccines generally must remain between 2°C and 8°C .

Some require much lower temperatures.

This uninterrupted system of refrigeration is the cold chain .

It protects vaccines from losing potency through excessive heat or accidental freezing.

The cold chain depends on reliable electricity, refrigerators and freezers, and temperature monitoring devices.

Cold boxes, vehicles, fuel, maintenance technicians, and trained health workers are also essential.

Failure at any point can leave jabs unusable or their quality uncertain.