Chinese scientists have developed a new messenger RNA (mRNA) vaccine that may provide long-term protection against several dangerous strains of the Ebola virus.
Ebola, also known as Ebola virus disease (EVD), is an acute hemorrhagic disease that causes fever, vomiting, internal bleeding, and organ failure, with a mortality rate of up to 50%. The virus is transmitted through contact with infected blood or bodily fluids, and prevention and treatment options remain limited.
According to the World Health Organization, there are currently licensed vaccines against Ebola, but they mainly target the Ebola Zaire strain, leaving other dangerous strains without effective protection, such as Sudan and Bundibugyo, which are associated with frequent outbreaks in Africa.
In an effort to develop more comprehensive protection, scientists designed a multi-strain vaccine called [GPs+NP]@LNP, based on the same technology used in COVID-19 vaccines. The vaccine works by sending genetic instructions to the body to produce specific viral proteins, which helps the immune system recognize and attack the viruses upon subsequent exposure.
The vaccine was designed by combining three surface glycoproteins (the virus's outer spike proteins that attach to and infect human cells) from different Ebola strains, along with an internal nucleoprotein that is highly similar across most strains. The surface proteins help stimulate antibody production, while the nucleoprotein activates immune cells capable of destroying infected cells.
According to the study published in the Proceedings of the National Academy of Sciences (PNAS), the vaccine showed strong results in animal trials. It achieved a 100% survival rate in mice exposed to the Ebola virus and significantly reduced viral levels in the blood and vital organs, such as the liver and spleen.
The vaccine also proved effective against the Bundybugyo and Sudan strains, helping to reduce the viral load in infected animals, while the hamsters maintained stable weights and eliminated viruses from their bloodstream.
One of the most notable findings of the study was that the immune protection lasted for a long period, reaching about 17 months after vaccination, which strengthens hopes for the possibility of developing a vaccine that provides extended protection against several deadly strains at once.
Despite the promising results, scientists emphasize that the vaccine is still in its early developmental stages, noting that the next step will involve testing it on non-human primates before moving on to clinical trials on humans.
