There are currently two malaria vaccines (the second was only approved at the end of 2023) that block the infection of liver cells by malaria parasites and are aimed at creating long-term immunity. However, their effectiveness is no more than 75% and requires booster shots. A new solution to this pressing problem has been developed by scientists from the London School of Hygiene & Tropical Medicine, who have developed a vaccination regimen for humans via the bites of genetically modified mosquitoes, reports Nature.
The insects are infected with modified versions of the parasite, which trigger the production of antibodies. Scientists designed the pathogen to persist in the body for no more than six days—a critical period after which it begins replicating in liver cells.
In a pilot study, the vaccine was tested on 10 volunteers. They were first "injected" with 50 mosquitoes, and three weeks later, exposed to regular mosquitoes infected with Plasmodium falciparum. The vaccine was 89% effective.
Scientists have not recorded any side effects other than mild itching at the bite site. They are now planning larger studies to confirm the safety and effectiveness of this new strategy in humans. If successful, it will provide a simple and affordable way to protect against malaria for many at-risk individuals.
According to statistics, approximately 600,000 people die from malaria in Africa every year. Recently, scientists presented another experimental mRNA vaccine that stops the liver from becoming infected and completely blocks the spread of the infection.
