A research team from Brazil’s Federal University of Santa Catarina intends to utilise technology to discover the ‘perfect’ protein to develop a malaria mRNA vaccine.
After the success of mRNA vaccines against COVID-19, scientists are cautiously optimistic that the same technology can be utilised to combat other widespread diseases, such as malaria. The technology is promising and has the potential to create an mRNA vaccine – however, its success will depend on the results of initial tests that are currently being conducted.
Is an mRNA vaccine possible?
A vaccine that successfully protects against all types of malaria has so far been elusive, due to the complexity of the parasite that is responsible for causing the disease. Thus, malaria remains a neglected disease, which means it has been overlooked by the research community.
“Neglected diseases affect poor populations,” explained Carlos Zarate-Bladés, an Immunologist at Brazil’s Federal University of Santa Catarina. “Any industry that may generate a product will first look at the market. If the market is not promising in financial terms, it would not even be tested.”
How is malaria spread?
Malaria is spread through the bites of Anopheles mosquitoes that are infected by Plasmodium parasites. In 2020, the disease was responsible for approximately 627,000 deaths worldwide, among 241 million cases, according to the World Health Organisation. In the same year, Africa registered 96% of malaria deaths – children under five are the most impacted and accounted for an estimated 80% of these deaths.
Malaria symptoms usually appear around ten to 15 days after infection and include fever, headache, and chills. If left untreated, the disease can become severe and may cause kidney failure, seizures, coma, and death. Groups at higher risk of developing severe disease include children under five, pregnant women, and people living with HIV/AIDS. WHO describes malaria as “both a consequence and a cause of poverty and inequality.”
How was the first vaccine developed?
The first malaria vaccine, recommended by the WHO in October 2021 for broad use in children, was an event that has been hailed as a historic moment. GlaxoSmithKline’s Mosquirix, also called RTS,S, offers protection against Plasmodium falciparum, the malaria-causing parasite that is prevalent in Africa.
However, it is ineffective against other types of Plasmodia, such as Plasmodium vivax, which is the dominant malaria parasite in most countries outside of Sub-Saharan Africa.
In Brazil, scientists are testing a recombinant protein-based vaccine against P. Vivax, which causes 89% of malaria cases in the country. In this vaccine technology, a piece of DNA is taken from the pathogen and inserted into manufacturing cells that are then able to produce a protein from the virus – or in the case of malaria, the parasite – that can be utilised as the malaria mRNA vaccine.
For the past two decades, Irene Soares, a microbiologist at the University of São Paulo, has been researching this potential malaria mRNA vaccine. Her team focuses on a P. Vivax protein that has a similar function to the one that has been utilised in the vaccine approved for Africa. This protein attacks the parasite to prevent it from getting into the blood and causing severe disease.
Tests in animals demonstrated that the vaccine is safe and offers protection. “Now we are at the stage of preparing this formulation for the first phase of trials in human beings,” concluded Soares.