Why was the 2018–2020 Ebola outbreak in Congo so hard to stop?

The 2018 to 2020 Ebola outbreak in eastern Congo was hard to stop because it took place in a conflict zone, where attacks interrupted the response and many people distrusted the local authorities or doubted the outbreak was real, even though a vaccine and treatments already existed. It still grew far larger than any earlier outbreak in the country: between 1 August 2018 and 25 June 2020 it resulted in 3,470 reported cases, and per United Nations numbers the final death toll was 2,280. Until it began, no outbreak had surpassed 320 cases in the Democratic Republic of the Congo.

A military conflict in the region that had begun in January 2015 hindered treatment and prevention efforts. The WHO described the combination of military conflict and civilian distress as a potential "perfect storm". In May 2019 it reported that since January, 85 health workers had been wounded or killed in 42 attacks on health facilities. In September 2018 all contact tracing and vaccinations were reported to stop for the foreseeable future in the town of Beni, after a deadly attack by rebel groups the day before.

Trust was the second front. According to a September 2018 Lancet survey, 25 percent of respondents in Beni and Butembo believed the outbreak to be a hoax, and these beliefs correlated with decreased likelihood of seeking healthcare or accepting vaccination. The IFRC has called funerals "super-spreading events", and safe burial teams formed by health workers were subject to suspicion.

A confirmed case in the city of Goma led the WHO to announce a Public Health Emergency of International Concern on 17 July 2019. New cases dwindled to zero by 17 February 2020; three more appeared in mid-April, and the outbreak was declared ended on 25 June 2020. Control relied on traditional measures: isolation of cases, contact follow-up, community engagement and safe burials.