For millennia, malaria has plagued humanity, causing fever, headache, and chills, which can quickly progress to severe illness and respiratory distress. A pathogen transmitted by mosquitoes, malaria is preventable and curable and yet continues to cause more than 600,000 deaths per year, primarily affecting sub-Saharan African children younger than 6.
A Sept. 12 Perry World House event, “Can the COVID Playbook Help End Malaria?”, looked at the historic fight against this disease, featuring discussions about new developments in mRNA vaccine technologies and lessons learned from the global COVID-19 pandemic.
Moderated by Carol McLaughlin, senior advisor for global public health at the Center for High Impact Philanthropy at the School for Social Policy & Practice and an infectious disease physician in the Perelman School of Medicine, the panel included Matthew Laurens, a pediatric infectious disease specialist at the Center for Vaccine Development; Martina Mchenga, a health economist and postdoctoral research fellow at the Center for Social Science Research at the University of Cape Town; and Drew Weissman, Roberts Family Professor in Vaccine Research in the Perelman School of Medicine.
Despite many new advances, progress on the fight against malaria has stalled, threatened by increasing resistance in mosquitoes as well as the parasites, McLaughlin said. “Now is the time when we really need new developments.”
Malaria has an adverse impact on not just the health but also the economy of the African region, Mchenga said, noting that the household cost of malaria is $16 dollars per day, while for many African countries, most of the population lives below the poverty line at less than $2.50 per day.
Laurens said developing a malaria vaccine has been difficult, in part because of the genetic diversity of the malaria parasite and the fact that scientists don’t yet know exactly which immune response the vaccine would need to stimulate to provide protection.
“The encouraging news is that, after 30 to 40 years of development, the very first malaria vaccine was approved by the World Health Organization in October of 2021,” Laurens said. “It is a moderately effective vaccine, but, for diseases like malaria that cause such death and destruction, it’s very critical to promote this vaccine in the areas that need it most.”
The vaccine, targeted at children who are at the highest risk for severe malarial consequences, requires four doses and provides about 50% protection after the first year it’s administered, Laurens said. After a few years, the efficacy tends to wane.
Recent studies have shown that this vaccine is most effective when layered on top of other protections like bed nets and seasonal malaria chemo prophylaxis, Laurens said. “We have a long way to go. But there is hope, and this vaccine was a high success.”
Weissman spoke to the use of mRNA technology and how it could impact malaria vaccine development. First, it stimulates potent immune responses, both in terms of antibodies and T cell immunity, which are both thought to be important in protecting against malaria, he said. Second, the technology enables scientists to target multiple antigens by adding multiple segments of RNA to a single vaccine.
“With RNA, we’ve put 20 different antigens in a single vaccine. And the thought from malaria is that one, two, maybe even three antigens is not going to be enough to give very broad protection, so being able to put 20 different antigens in one vaccine gives RNA a big advantage.”
When seeking lessons drawn from COVID-19 that could apply to malaria vaccine development, Mchenga said, it is important to consider the supply chain and remember that not all countries have the ability to store and distribute vaccines. As scientists develop new technologies, they also need to be thinking about countries’ varying needs, modifying vaccine rollout for maximum effectiveness and equity, he said.
Laurens said that one of the lessons from the COVID 19 pandemic is that, when public-private partnership, political will, and financing come together, a vaccine can be rapidly developed and deployed. “We should take this lesson to malaria,” he said.
“Community buy-in is essential for any successful clinical trial or vaccination program, and we’ve learned that time and time again,” he said. “We need to make these vaccines locally; we need to test them locally.”
Scientists did not effectively introduce the COVID-19 mRNA vaccines and explain why they were safe, Weissman said, noting that many lay people thought the vaccines were rushed through the approval process and could be dangerous.
In malaria-endemic areas, many people have been touched by the disease, more so than COVID-19, so theywould be more excited about a vaccine, Laurens said. In addition, working with trusted community health workers and through the proper channels would help with communication.
Another challenge to vaccine rollout will be the cost, Weissman said. “The Gates Foundation says $1.50 a dose for a vaccine is affordable and reasonable. Making RNA or any kind of vaccine at $1.50 a dose is not going to be easy.”
The financial piece is key, along with getting community involvement and government support, he said. “It’s a big puzzle. All of the pieces have to be there and have to fit together for this to be able to work.”
“If we have a package of malaria vaccines for people who really need them,” Mchenga said, “then the future is looking good.”