Three new vaccines are being developed to tackle the rare Bundibugyo species of Ebola, which has already killed nearly 250 people, according to the BBC. The International Aids Vaccine Initiative (IAVI) said the outbreak is threatening to be the worst ever. The University of Oxford and the pharmaceutical company Moderna are also researching vaccines against the Bundibugyo species. The Coalition for Epidemic Preparedness Innovations (Cepi) is providing funding to each group, stating that “every day counts” in the race to control the outbreak.

Outbreak in DR Congo and Neighboring Countries

There are now more than 1,000 suspected cases in the Democratic Republic of Congo (DR Congo), with nine confirmed cases in neighboring Uganda. The outbreak, which was detected only after it had spread in a conflict zone with limited healthcare resources, has raised concerns that it could reach the size of the largest Ebola outbreak in West Africa in 2014-16. That outbreak infected nearly 29,000 people and resulted in more than 11,000 deaths. Dr. Mark Feinberg, head of IAVI, said the current situation is “clearly threatening to be as severe an outbreak as that, if not even worse” and that vaccine development is a priority.

Vaccine Development Efforts

Vaccines must be developed for each individual species of Ebola,there are six, but only three are known to cause outbreaks. There is currently a vaccine for the most common Zaire species, but this outbreak is being caused by the Bundibugyo species, which has only been seen twice before and has no approved vaccine. IAVI is working on a modified version of the Zaire Ebola vaccine to fight Bundibugyo. The experimental jab has been tested in monkeys where it rapidly trained the immune system and provided close to 100% protection.

Feinberg said their evidence so far means he is “optimistic about the potential” but that it would take seven to nine months to get the vaccine ready for clinical trials, although they are trying to “accelerate those timelines.” Meanwhile, pharmaceutical company Moderna is using its mRNA technology,similar to what was used in the rapid development of vaccines during the Covid pandemic,to work on a Bundibugyo vaccine. Stéphane Bancel, CEO of Moderna, said the company would “move with urgency and scientific rigor” to support the response and help bring a potential vaccine closer to communities in need. Moderna’s vaccine should be ready for clinical trials in two to three months.

Different Approaches to the Same Goal

Each vaccine aims to train the body to recognize the same structure on the surface of the virus—known as the Bundibugyo glycoprotein—but each uses a different technology to achieve this. IAVI uses a live, but harmless virus that has been engineered to also contain the Ebola glycoprotein. The immune system fights off the harmless virus and learns to fight Ebola in the process. The mRNA vaccine and the Oxford vaccine both deliver a snippet of genetic code into the body, which orders the construction of the Bundibugyo glycoprotein. The body then recognizes it as foreign and starts to attack it, giving the immune system a head start in fighting a real Ebola infection.

However, differences in the technologies and the way they train the immune system could affect the levels of protection or the number of doses needed. These factors need to be tested in clinical trials. Cepi is funding the early stages of research. Dr. Richard Hatchett, CEO of Cepi, said: “With Bundibugyo virus spreading rapidly and no licensed vaccines, every day counts in the race against this deadly disease.” Dr. Tedros Adhanom Ghebreyesus, director general of the World Health Organization, added that a Bundibugyo vaccine could help control the current epidemic and strengthen preparedness for future outbreaks.