Chemical engineers at McMaster University dried live viral vaccines with a sugar solution that can be stored at 40 C for months with no ill effects

A team of Canadian scientists has developed what could be a simple and inexpensive method to preserve vaccines without refrigeration — a potential public-health game changer in parts of the world where epidemics are raging and resources are limited.

A chemical engineering team at McMaster University, spearheaded by recent PhD graduate Vince Leung and supervised by professor Carlos Filipe, combined herpes and influenza A vaccines — chosen because they’re among the most fragile and sensitive to heat — with a sugar solution and dried the mixture into a thin film.

They stored this at a desert-like 40 degrees Celsius for weeks before reconstituting it in saline solution and testing it in mice.

The vaccines were as safe and as effective as they would have been “fresh out of the fridge,” Filipe said. The flu vaccine was still good after three months, and the herpes after two.

The research, published Tuesday in the journal Scientific Reports, is the first to use this method to preserve vaccines. The team also tested a pneumonia vaccine and an experimental Ebola vaccine using the same process. They passed the test too.