Cold-Chain-Free Malaria Vaccine Induced Durable Anti-Malaria Immunity

Malaria is a deadly disease killing more than half a million people every year, but a new vaccine is showing promise as it not only offers long-lasting strong protection but also inhibits transmission of malaria by mosquitos.

The vaccine is predicted to be low cost and its cold-chain independence strongly enhances its deployability.

Professor Bernd Rehm, Director of the Centre for Cell Factories and Biopolymers within Griffith University’s Institute for Biomedicine and Glycomics, and his team led the development of a next-generation malaria vaccine.

“Existing vaccines offer only partial and short-lived protection and are difficult to distribute across the globe as they require strict refrigeration,” Professor Rehm said.

“The difference with our vaccine is that not only does it not require refrigeration, but it also takes a different approach when targeting the malaria parasite.

“It attacks two critical stages at once – before infection and during transmission by stopping the parasite from reaching and infecting the liver, and also by preventing parasites from developing inside mosquitoes and spreading to others.”

The vaccine works by using tiny, safe particles made by engineered bacteria.

The particles acted like a scaffold which displayed key malaria proteins on their surface, training the immune system to recognise and destroy the parasite.

The dual-target strategy gave the immune system more ways to fight malaria and reduced the chance of the parasite escaping from the mosquito into the human body.

Results showed the vaccine reduced malaria infection in the liver by up to 80 per cent, completely protected one in four from developing malaria, produced antibody levels well above those needed for protection, and strongly reduced parasite transmission by mosquitoes by around two-thirds.

Furthermore, the vaccine offered immunity protection for at least six months, exceeding the longevity of many existing malaria vaccine candidates.

Lead author on the research paper, Dr Nivethika Sivakumaran, said: “One of the biggest challenges in malaria-affected regions is keeping vaccines cold and viable while in storage, and during transportation.”

Co-author Dr Shuxiong Chen said: “This new vaccine remains stable and effective for at least a month in 37°C degree weather, drastically improving access to rural and remote areas.”

The paper ‘Robust bioconjugated antigens induce immune responses preventing malaria infection and its transmission’ has been published in Small.