The second-largest Ebola outbreak on record is over after nearly two years and more than 2,200 deaths, the Democratic Republic of Congo said on Thursday, even as a separate flare-up of the virus continued elsewhere in the country.

In spite of effective vaccines and treatments that dramatically boosted survival rates when administered early, the outbreak dragged on as first responders struggled to gain access to virus hotspots in Congo’s restive eastern borderlands. As that outbreak neared its end, another one was declared on June 1 in the western city of Mbandaka, more than 1,000 km (620 miles) away.