The Ebola outbreak raging in the Democratic Republic of Congo is growing "exponentially,” the United Nations' senior Ebola coordinator warned Friday. The Ebola outbreak is already the biggest in the country's history having killed more than 2,300 people from more than 5,000 cases, according to the African Union health agency. The virus eruption is "growing exponentially," Julien Harneis told reporters in Geneva, speaking from DRC. On Thursday, the World Health Organization said Congo has been allocated 70,000 doses of Merck's Ervebo vaccine for Ebola. Last week Congo had requested a release of Ervebo vaccines from the global Ebola virus disease vaccine stockpile, managed by the International Coordinating Group (ICG) on Vaccine Provision, according to WHO. The health agency said the group allocated 70,000 Ervebo doses for Congo, of which 20,000 shots will be used in a late-stage trial to understand the impact of the vaccine on the Bundibugyo virus. Geneva-based global vaccine alliance Gavi said they would provide $7 million to fund the shipment to Congo along with another $6 million to help with vaccination efforts in high-risk areas. The ongoing outbreak is caused by the Bundibugyo species of Ebola, which has no approved vaccines or treatments. "It is not known whether Ervebo may be protective against the Bundibugyo virus in humans," WHO said, stressing the importance of clinical trials to provide new evidence. Ervebo is approved to prevent disease caused by the more common Zaire ebolavirus strain.