Research and analysis

Outbreaks under monitoring: week 35 (week ending 30 August 2026)

Updated 3 September 2026

The following signal relates to an ongoing outbreak, with data as of 31 August 2026

Disease or pathogen	Bundibugyo virus disease (BVD)
Location	Multi-country
Status	Update
Reporting date	15 May to 31 August 2026
Summary	On 15 May 2026, an outbreak of Ebola disease caused by Bundibugyo virus was declared in the Democratic Republic of the Congo (DRC) and Uganda. On 17 May 2026, the World Health Organization (WHO) Director-General determined that the outbreak constitutes a public health emergency of international concern. The outbreak in DRC remains a public health emergency of international concern as of the latest WHO Emergency Committee meeting, held on 18 August 2026. As of 31 August 2026, 6,186 confirmed cases and 3,007 confirmed deaths have been reported in the DRC. This is an increase of 530 confirmed cases and 292 deaths since the last Outbreaks Under Monitoring report. Cases have been reported in 60 health zones across 6 provinces (Ituri, North Kivu, South Kivu, Haut-Uele, Bas-Uele and Tshopo). The highest number of cases continue to be reported in Ituri (5,065 cases, including 2,305 deaths). This has become the largest recorded BVD outbreak and is the second largest Ebola disease outbreak. On 27 August 2026, WHO and the Africa Centres for Disease Control and Prevention declared the end of the outbreak in Uganda following no new cases since the last case was discharged from care on 16 July 2026. A total of 20 confirmed cases (including 2 deaths) were reported in Uganda. The last case was reported on 21 June 2026. Of the confirmed cases, 15 were imported from the DRC and 5 were secondary cases among contacts. This is the 17th recorded Ebola disease outbreak in the DRC since the virus was first identified in 1976. The last reported outbreak, in Kasai Province, ended in December 2025. Bundibugyo virus was first identified in 2007 in Bundibugyo district, western Uganda. A second outbreak caused by Bundibugyo virus was reported in DRC in 2012. WHO continues to assess the risk of this event as very high in the DRC, high for countries with land borders adjoining the DRC, and low for the remaining countries in the African region, and globally. As of 31 August 2026, no imported cases associated with this outbreak have been reported in the UK. Previous experience from the 2014 to 2016 West Africa outbreak suggests a limited importation risk, with only one travel-related case reaching the UK outside of medical evacuations. The risk of the current outbreak to the UK population is assessed as low.
Further information	Ebola: overview, history, origins and transmission Ebola virus disease: clinical management and guidance Ebola and Marburg haemorrhagic fevers: outbreaks and case locations UKHSA blog: What is Ebola and how does it spread? NaTHNaC country information page: Democratic Republic of the Congo and Uganda

Epidemiological week 35, 24 to 30 August 2026

Disease or pathogen	Crimean-Congo haemorrhagic fever (CCHF)
Location	Afghanistan and Austria
Status	Update and New
Reporting date	July to 28 August 2026
Summary	In July 2026, 302 new suspected cases of CCHF and 9 associated deaths were reported in Afghanistan. This represents a 37.5% decrease in cases compared to June 2026 (483 cases and 21 deaths). A total of 1,258 cases and 55 deaths have been reported in Afghanistan in 2026. On 28 August 2026, the Vienna Health Association (in German) reported a confirmed case of CCHF in Vienna, Austria. The case had recently returned from a trip to the Middle East (unspecified country), where infection occurred. In response, the case has been hospitalised and isolated, and is reported to be in a stable condition. This is the first ever confirmed case of CCHF in Austria. CCHF is not present in the UK, nor are there any identified established populations of Hyalomma ticks, the principal vectors of CCHF virus. Confirmed CCHF cases have been imported into the UK, including one fatal case in 2012 and one in 2014.
Further information	Crimean-Congo haemorrhagic fever: origins, reservoirs, transmission and guidelines HAIRS risk assessment: Crimean-Congo haemorrhagic fever NaTHNaC country information page: Afghanistan and Austria

Disease or pathogen	Mpox
Location	Chile
Status	New
Reporting date	28 August 2026
Summary	According to the Pan American Health Organization, in June 2026, Chile reported a case of clade Ib mpox in an individual who had travelled to Spain and Italy. This is the first reported case of clade Ib mpox in Chile. Clade II mpox has been reported in Chile since 2022. In the UK, cases of clade Ib and IIb mpox continue to be reported. Up to 31 July 2026, 119 clade Ib mpox cases have been reported, most of which have direct or indirect travel links to countries where clade Ib mpox is circulating.
Further information	Mpox: guidance Mpox clade Ib and clade IIb outbreak: epidemiological overview NaTHNaC country information page: Chile