Ebola outbreak: When will a vaccine be developed for the new strain?

The Bundibugyo strain of Ebola has a fatality rate of up to 50 percent and no approved vaccine as yet. The World Health Organization (WHO) has declared that the latest outbreak of a rare strain of the Ebola virus in Democratic Republic of the Congo (DRC) and Uganda is a “public health emergency of international concern”. No vaccine or treatment exists for the new Bundibugyo strain of Ebola, a disease whose strains have killed more than 15,000 people in Africa in the past half-century. The previous Ebola outbreak in West Africa, which lasted between 2013 and 2016, killed at least 11,000 people, according to the Library of Medicine. So, how quickly can a vaccine be developed to contain the latest strain? Here’s what we know What is the situation so far? The epicentre of the latest outbreak is in DRC’s northeastern province of Ituri, close to the borders with Uganda and South Sudan, whose status as a gold-mining hub leads to people regularly crossing it. The virus has also spread into neighbouring provinces of DRC, as far as 200km (125 miles) away from what has been identified as the epidemic’s “ground zero” as well as beyond the DRC’s borders. The toll from the latest strain of the Ebola outbreak has risen to an estimated 131 deaths from 513 suspected cases, Health Minister Samuel Roger Kamba told the media on Tuesday. Over the past 24 hours, 26 more cases have been suspected. In Uganda, according to the WHO, at least one person has died and two more people have been infected with the latest strain of the virus. Uganda government spokesperson Alan Kasujja told Al Jazeera’s Catherine Soi that more than 120 people are being quarantined and added that he is confident Uganda can control the spread of the virus. Fear has, however, gripped both countries. In the DRC, from Bukavu to Kinshasa, concern is spreading among residents and street vendors as Ebola cases rise. In cities hundreds of miles apart, people are wearing face masks and calling for stronger protections from the latest outbreak. “I am afraid of bringing the disease home to my family because I spend the whole day transporting people. I am afraid of dying, that is what scares me so much,” a motorbike driver in the country told Al Jazeera. “Last time [between 2013 and 2016], it killed a lot of people and we heard that it has reappeared, which makes us very afraid. Especially those of us who sell things in the street. We are in contact with people we do not know and that really frightens us,” Marie Evuto, a street vendor, said. The WHO chief, Tedros Adhanom Ghebreyesus, said on Tuesday that he is “deeply concerned about the scale and speed of the epidemic”. “Early on Sunday, I declared a public health emergency of international concern over an epidemic of Ebola disease in the Democratic Republic of the Congo and Uganda,” Tedros told the World Health Assembly in Geneva. What do we know about the new strain? How deadly is it? The Bundibugyo strain of Ebola is a distinct species within the Ebola virus family. It differs from the Zaire Ebola virus strain, which caused the large 2014-2016 West Africa outbreak, Krutika Kuppalli, associate professor at the Infectious Diseases and School of Public Health at UT Southwestern Medical Center in Dallas, Texas, told Al Jazeera. “While Bundibugyo has caused fewer outbreaks historically, it is still a very serious pathogen. Prior outbreaks have had case fatality rates ranging from approximately 30-50 percent, and the current outbreak is particularly concerning because there are currently no licensed vaccines or specific therapeutics for Bundibugyo virus disease,” she said. Kuppalli added that ongoing conflicts in the region, which have been accompanied by vast population displacement, weak surveillance systems and delayed detection, will make the latest outbreak more challenging to contain. “Early cases may have been missed in part because many front-line diagnostic platforms were optimised for Zaire Ebola virus and do not reliably detect Bundibugyo virus,” she said. “We are now seeing this strain of the virus spread into urban and cross-border settings, which raises concern about amplification if containment measures are not rapidly strengthened,” she warned. Will there be a vaccine? There is currently no approved vaccine for this strain of the Ebola virus. A vaccine named Ervebo, manufactured by Merck, which was used against the Zaire strain of Ebola, has been shown to provide some protection against Bundibugyo in animal studies. Kuppalli from the UT Southwestern Medical Center explained that vaccine development timelines are difficult to predict. “The scientific community is not starting from zero as there is already extensive knowledge from prior Ebola vaccine work, including viral vector and mRNA platforms that could potentially be adapted for Bundibugyo virus,” she said. “However, moving from candidate design to clinical trials, manufacturing, regulatory review, and deployment still takes time, particularly durin