The world was unprepared for COVID-19 — but it has responded remarkably to the challenge of a pandemic. Nearly one year into the outbreak, 172 countries are involved in researching vaccine candidates for the virus.

On the surface, it looks like a new level of equity in global health has been achieved through the pandemic. But while developing the vaccine is a joint effort, access to it could be stymied by poor health systems and lack of infrastructure.

The scale of global vaccination needed to achieve some level of immunity to the virus is unprecedented — and almost unbelievable. India alone will have to vaccinate around 900 million of its people to reach the desired herd immunity threshold. In Africa, the number is pegged at 750 million people, many of who live in rural communities with limited access to healthcare.

The problem is the supply chain. Producing a vaccine, once it is researched, is relatively easy. But getting it to people requires a tangled network of shipping, storage, freezing, communication and healthcare that will be difficult to deliver globally — especially on the last mile of the journey.

“It’s the biggest logistical challenge the world has ever seen,” says Toby Peters, professor of cold economy at the University of Birmingham. “You’ve got a volume of vaccines that has never been tackled before, the speed requirements and the problem of outreach.”

Peters is involved in a research project in Bangladesh to develop a blueprint for future large-scale vaccination programmes in the global South. Supplying rural healthcare centres and remote villages at the end of the “gnarly” last mile is where logistics falter and up to 25 per cent of vaccine doses are lost, he says.

Read the full article about the COVID-19 vaccine cold chain by Inga Vesper at SciDev.Net.