A critical mutation in the Ebola virus that greatly increased its infectivity during a huge outbreak has been discovered by Chinese researchers, offering fresh information for epidemic surveillance and medication development.

The study, which was published in the journal Cell, concentrated on the second-largest Ebola virus disease (EVD) outbreak in history, which occurred in the Democratic Republic of the Congo (DRC) between 2018 and 2020 and resulted in over 3,000 illnesses and over 2,000 deaths, according to Xinhua news agency.

According to the research, “real-time genomic surveillance and evolutionary analysis of the pathogen are crucial during major emerging infectious disease outbreaks,” said Sun Yat-sen University professor Qian Jun.

“This is not only able to warn of changes in transmission risk but also to prospectively assess the effectiveness of existing drugs and vaccines, guiding us to preemptively adjust control strategies,” Jun stated.

The research was motivated by a central question: does viral evolution itself contribute to the extended length of the Ebola outbreak, independent of the effects of regional healthcare challenges?It has long been known that during significant epidemics, important viral changes frequently function as unseen accelerators of transmission.

“We had to look into whether similar patterns of mutation existed for this virus after working on Ebola for more than ten years,” Jun explained, outlining the team’s purpose.

After analyzing 480 full Ebola virus genomes in 2022, the scientists found that GP-V75A, a variation with a particular mutation in the viral glycoprotein, had appeared early in the DRC epidemic.

According to the research team, this variant quickly supplanted the original strain, and its increasing predominance closely matched the increase in case numbers, indicating it might provide a transmission benefit.

The biological effect of the mutation was validated by later tests using different models. It shown that GP-V75A had greatly increased the virus’s capacity to infect mice and many host cell types.

Additionally, this study identified a serious clinical concern: the GP-V75A mutation had reduced the antiviral efficacy of various therapeutic antibodies and small-molecule entry inhibitors now in use, suggesting a potential danger of drug resistance.

According to the research team, these results highlight the significance of ongoing viral genome monitoring during epidemics in order to foresee evolutionary dangers and guide the creation of broad-spectrum countermeasures.