After a 42-day period without any new cases, the World Health Organization (WHO) has declared the Ebola outbreak in the Democratic Republic of Congo over.

Initially announced on May 12 in Likati, a remote town in the Bas-Uélé province close to the Central African Republic border, the outbreak resulted in a total of eight cases—with four of those patients dying. While it has declared the outbreak over, WHO says “enhanced surveillance” will continue in the country. The period of 42 days without a new case is significant because it means that two 21-day incubation cycles of the virus have passed.

The containment of the outbreak, the eighth in DR Congo since 1976, has been credited to a swift response by local authorities, including timely alerts of suspected cases and immediate testing of blood samples. In total, 583 people believed to have had contact with the suspected cases were tracked and closely monitored. In addition, DR Congo’s health ministry approved the use of a new experimental vaccine in a bid to stop the outbreak. During trials of the vaccine conducted in Guinea, thousands of people tested were all confirmed as virus-free within 10 days.

These tactics helped DR Congo prevent higher casualty count as seen in the 2014 outbreak which mainly affected West Africa. DR Congo escaped with relatively few deaths in 2014: Among the more than 11,000 deaths across West Africa, DR Congo recorded a total of 49 deaths that year. The worst of the epidemic hit Guinea, Liberia, and Sierra Leone.

Going forward, WHO says it will, in partnership with the DR Congo government, work to ensure that the four survivors who recovered from the being infected by the virus have continued access to healthcare and are successfully reintegrated into the local community without stigmatization. For its part, DR Congo’s government says it will “now focus all our efforts on strengthening the health system in Bas-Uélé province, which has been stressed by the outbreak.”