An estimated 400,000 people die each year from malaria, especially children under 5 years old. This is comparable to the number of people who now die from Covid-19. That is why a vaccine has long been worked on for this disease (with far fewer funds than for Covid-19). Unfortunately, this is a long way off.
There are many success stories in the scientific literature about new methods or promising medicines or vaccines. Studies with negative outcomes are published much less often. However, this is important, because negative data also provides knowledge and prevents studies from being repeated unnecessarily. Especially in the case of animal experiments it is important to prevent this.
A promising vaccine
Oxford researchers have designed a potential malaria vaccine that gave a good immune response in mice. When we tested this vaccine in rhesus monkeys in a collaboration, this also provoked a good immune response in these animals. You might think this is a reason for hope, but it does not yet prove that it also offers protection against disease.
Nature is still difficult to predict
Unfortunately, we still don't know exactly what type of immune response is exactly important for a malaria vaccine to provide protection. A good immune response gives reason for optimism, but you can only be sure whether a vaccine works, after you have tested whether it actually offers protection against disease.
To determine whether the vaccine offered protection, the vaccinated rhesus monkeys were infected with monkey malaria parasites. At the same time, a control group of animals that had not received a vaccine was infected with the same parasites. This allows you to determine exactly what the difference is between animals that had or had not received the vaccine. Unfortunately, there was no difference between the two groups and the vaccine therefore did not protect against malaria.
Don’t throw in the towel
New studies have recently shown that certain modifications to this type of vaccine can provide protection in a mouse model. This therefore offers new directions for further research.
We published the above work in the magazine "Vaccines". In this way we prevent unnecessary repetition of animal experiments. In addition to a vaccine, new drugs against malaria are also urgently needed. Especially against a dormant form of the parasite that can hide in the liver to cause a new infection at a later time. We recently received a grant to further develop an innovative culture system for testing new medicines against this form of malaria.