Global high consequence infectious disease events: summary May 2024

Question 1

Interpreting this report

Accepted Answer

The report provides updates on known, high consequence infectious disease (HCID) events around the world as monitored by UK Health Security Agency’s (UKHSA) epidemic intelligence activities.

The report is divided into 2 sections covering all the defined HCID pathogens. The first section contains contact and airborne HCIDs that have been specified for the HCID programme by NHS England. The second section contains additional HCIDs that are important for situational awareness.

Each section contains information on known pathogens and includes descriptions of recent events. If an undiagnosed disease event occurs that could be interpreted as a potential HCID, a third section will be added to the report.

Events found during routine scanning activities that occur in endemic areas will briefly be noted in the report. Active surveillance, other than daily epidemic intelligence activities, of events in endemic areas will not be conducted (for example, actively searching government websites or other sources for data on case numbers).

The target audience for this report is any healthcare professional who may be involved in HCID identification, treatment and management.

Risk rating

Included for each disease is a current risk rating based on the probability of introduction to the UK and potential impact on the UK public. Past UK experience and the global occurrence of travel-associated cases are also considered. Currently, all diseases are classified into one of 3 categories: Low, very low and exceptionally low to negligible.

Question 2

Contact HCIDs

Accepted Answer

Crimean-Congo haemorrhagic fever (CCHF)

Geographical risk areas	Endemic in Africa, the Balkans, the Middle East and western and south-central Asia. Cases have also been reported in Russia and Georgia. Spain has previously reported locally acquired cases (first reported in 2016, with the latest case reported in 2024) .
Sources and routes of infection	• bite from, or crushing of, an infected tick • contact with the blood, tissues or body fluids of infected humans or animals
UK experience to date	Two cases have been reported in individuals who have travelled to the UK from Afghanistan in 2012 and Bulgaria in 2014.
Risk rating	Low – rarely reported in travellers.
Recent cases or outbreaks	Between 1 January and 25 May 2024, the World Health Organization (WHO) reported 165 CCHF cases, including 4 deaths, from Afghanistan. CCHF was confirmed in 20 out of 106 suspected cases tested. Confirmed cases were from 5 provinces, including Kabul, Balkh, Kapisa, Helmand and Paktika. In 2023, Afghanistan reported 1,243 CCHF cases (383 confirmed), including 114 deaths (case fatality rate (CFR) of 9.2%). On 12 May 2024, media reported that Iran had recorded 3 cases of CCHF, including one death in Hormuzgan Province; the reporting period of these cases is not specified. Media reports that Iraq recorded 50 CCHF cases, including 8 deaths, between 1 January and 22 May 2024. On 30 and 31 May 2024, the media reported a fatal case of CCHF from Diayala and Kiruk Governorates of Iraq. On 22 May 2024, the media reported that the Kurdistan Regional Government recorded 2 cases of CCHF, which are the first reported cases for 2024 in this area. Media reported, on 3 May 2024, that 108 suspected CCHF cases, including one death had been detected in the Kyzlorda region of Kazakhstan, so far in 2024. On 14 May 2024, the North Macedonia Institute of Public Health reported 2 confirmed cases of CCHF. On 5 May 2024, the media reported a fatal case of CCHF in Punjab Province, Pakistan, with an additional case reported from Punjab on 10 May 2024, and 2 further fatal cases reported from this province on 27 May 2024. On 26 May 2024, the media reported a suspected CCHF-related death in Khyber Pakhtunkhwa Province of Pakistan. In Russia, on 13 May 2024, the media reported 4 confirmed cases of CCHF in the Stavropol region, with a further 6 confirmed cases reported in the Rostov region on 23 May 2024. On 10 May 2024, media reported one case of CCHF in Matam region in Senegal. In Turkey, on 27 May 2024, media reported that 2 confirmed cases of CCHF had been recorded in Tokat Province.

Ebola virus disease (EVD)

Geographical risk areas	Map of countries which have reported EVD cases up to January 2023. No outbreaks of EVD have since been reported.
Sources and routes of infection	• contact with blood, tissues or body fluids of infected animals, or consumption of raw or undercooked infected animal tissue • contact with infected human blood or body fluids
UK experience to date	Four confirmed cases (one lab-acquired in the UK in 1976, 3 healthcare workers associated with West African epidemic 2014 to 2015).
Risk rating	Very low – other than during the West Africa outbreak, exported cases are extremely rare.
Recent cases or outbreaks	No confirmed or suspected human cases were reported in May 2024.

Lassa fever

Geographical risk areas	Endemic in sub-Saharan West Africa.
Sources and routes of infection	• contact with excreta, or materials contaminated with excreta from an infected rodent • inhalation of aerosols of excreta from an infected rodent • contact with infected human blood or body fluids
UK experience to date	Three travel-related Lassa fever cases reported in 2022. Prior to this, 8 imported Lassa fever cases had been reported since 1980, all in travellers from West Africa.
Risk rating	Low – overall, Lassa fever is the most common imported viral haemorrhagic fever (VHF) but importations to the UK are still rare.
Recent cases or outbreaks	On 2 May 2024, France reported its first recorded case of Lassa fever. The case was a soldier that had returned from abroad (country not specified). Between 1 January and 17 May 2024, Liberia has reported a total of 42 Lassa fever cases (11 confirmed; 31 suspected), including 4 deaths. This is an ongoing outbreak since January 2022. Between 1 January and 17 May 2024, Nigeria reported 6,954 Lassa fever cases (871 confirmed, 6,083 suspected) and 159 deaths amongst confirmed cases (CFR of 18.2%). Confirmed cases have been reported from 28 out of 36 states. Compared to the same period in 2023, this is a 12% increase in new cases reported.

Marburg virus disease (MVD)

Geographical risk areas	Sporadic outbreaks have previously been reported in Central and Eastern Africa. A human case of MVD was reported in August 2021 in Guinea; this was the first case to be identified in West Africa. MVD cases were reported in Ghana for the first time in July 2022. MVD outbreaks were reported for the first time in Equatorial Guinea in February 2023 and in Tanzania in March 2023.
Sources and routes of infection	• exposure in mines or caves inhabited by Rousettus bat colonies • contact with infected human blood or body fluids
UK experience to date	No reported cases in the UK.
Risk rating	Very low – globally, 5 travel-related exported MVD cases have previously been reported in the literature.
Recent cases or outbreaks	No confirmed or suspected human cases were reported in May 2024.

Question 3

Airborne HCIDs

Accepted Answer

Avian influenza A(H7N9) virus

Geographical risk areas	All reported human infections have been acquired in China.
Sources and routes of infection	• close contact with infected birds or their environments • close contact with infected humans (no sustained human-to-human transmission)
UK experience to date	No known cases in the UK.
Risk rating	Very low (UKHSA risk assessment).
Recent cases or outbreaks	No confirmed or suspected human cases were reported in May 2024.

Avian influenza A(H5N1) virus

Geographical risk areas	Human cases have been predominantly reported in South East Asia, but also in Egypt, Iraq, Pakistan, Turkey and Nigeria. Human cases (clade 2.3.4.4b) were reported in Spain and the USA in 2022 and 2024, and in the UK in 2022 and 2023. The first human cases of avian influenza A(H5N1) (clade 2.3.4.4b) were reported from South America in 2023, from Ecuador and Chile. Since October 2023, several human cases of clade 2.3.2.1c have been reported in Cambodia.
Sources and routes of infection	• close contact with infected animals (notably birds) or their environments • close contact with infected humans (no sustained human-to-human transmission)
UK experience to date	As of September 2023, 5 detections were reported in the UK, one in 2022 and 4 in 2023.
Risk rating	Very low (UKHSA risk assessment).
Recent cases or outbreaks	On 22 May 2024, the United States Centres for Disease Control and Prevention (US CDC) reported a confirmed human case of avian influenza A(H5) in Michigan State. This is the second case associated with the ongoing multi-state outbreak of avian influenza A(H5N1) in dairy cattle. This was later confirmed to be avian influenza A(H5N1) (clade 2.3.4.4b) through genetic sequencing. On 30 May 2024, the US CDC reported a third human case of avian influenza A(H5) associated with the outbreak of avian influenza A(H5N1) in dairy cattle (designation of the virus neuraminidase is pending genetic sequencing). This case is also from Michigan state. The case had exposure to infected dairy cattle and is not linked to the previous 2 cases. On 21 May 2024, the Victoria State Government of Australia reported a human case of avian influenza A(H5N1). The case, which occurred in March 2024, was a child with recent travel to India. The individual experienced a severe infection but has subsequently recovered. The isolated virus was later sequenced and identified as clade 2.3.2.1a. On 28 May 2024, the Hong Kong Centre for Health Protection reported a human case of avian influenza A(H5N1) that occurred in the Guanxi Zhuan Autonomous Region, China on 11 May 2024. The case, who has recovered, is reported to be a cargo port delivery worker from Vietnam with no local travel in Mainland China. No further details were provided.

Middle East respiratory syndrome (MERS-CoV)

Geographical risk areas	The Arabian Peninsula – Bahrain, Jordan, Iraq, Kingdom of Saudi Arabia, Kuwait, Oman, Qatar, United Arab Emirates, Yemen. Evidence has also been reported in Iran and Kenya.
Sources and routes of infection	• airborne particles • direct contact with contaminated environment • direct contact with camels or consumption of raw camel milk
UK experience to date	Five MERS-CoV cases in total – 3 imported cases (2012, 2013 and 2018), 2 secondary cases in close family members of the case in 2013, 3 deaths.
Risk rating	Very low (UKHSA risk assessment).
Recent cases or outbreaks	During May 2024, 3 human cases of MERS-CoV infection were reported to the WHO from Saudi Arabia. One of the cases was fatal, with all 3 cases epidemiologically linked to a healthcare facility. Since the beginning of 2024, a total of 4 cases and 2 deaths have been reported from Saudi Arabia. As of 8 May 2024, a cumulative total of 2,613 MERS-CoV cases and 941 deaths have been reported globally since April 2012.

Mpox (Clade I only)

Geographical risk areas	Central Africa including, Central African Republic, Cameroon, the Democratic Republic of the Congo (DRC), Gabon and Republic of the Congo.
Sources and routes of infection	• close contact with an infected animal (in an endemic country) or an infected person • contact with clothing or linens (such as bedding or towels) used by an infected person • direct contact with mpox skin lesions or scabs • coughing or sneezing of an individual with an mpox rash • consumption of contaminated bushmeat
UK experience to date	No cases of Clade I mpox have been reported in the UK.
Risk rating	Very low – no known importations of Clade I mpox into the UK.
Recent cases or outbreaks	Sequencing data is often not available for mpox cases reported from endemic African countries where Clade I mpox is known to circulate. Therefore, we report below all reported mpox cases from these countries, regardless of whether the samples have been sequenced or clade-tested. Between 1 January and 24 May 2024, the Democratic Republic of the Congo (DRC) has reported 7,281 mpox cases (884 confirmed), including 374 deaths (CFR of 5.1%), from 23 of 26 provinces. During 2023, the DRC reported its highest annual number of mpox cases (14,434 cases, including 728 deaths). Between 1 January and 24 May 2024, the Central African Republic has reported 110 mpox cases (21 confirmed (no deaths)). So far, 14 out of 35 districts have reported mpox cases. During 2023, 67 mpox cases, including 2 deaths were reported. In the Republic of the Congo, as of 17 May 2024, 87 mpox cases (19 confirmed (no deaths)) were reported from 5 out of 12 provinces. During 2023, 95 mpox cases, including 5 deaths were reported.

Nipah virus

Geographical risk areas	South East Asia, predominantly in Bangladesh and India. Cases have also been reported in Malaysia and Singapore.
Sources and routes of infection	• direct or indirect exposure to infected bats • consumption of contaminated raw date palm sap • close contact with infected pigs or humans
UK experience to date	No known cases in the UK.
Risk rating	Exceptionally low to negligible – no travel-related infections in the literature.
Recent cases or outbreaks	No confirmed cases of Nipah virus infection were reported in May 2024.

Pneumonic plague (Yersinia pestis)

Geographical risk areas	Predominantly sub-Saharan Africa but also Asia, North Africa, South America, Western USA. Endemic in Madagascar, Peru, and the DRC.
Sources and routes of infection	• flea bites • close contact with infected animals • close contact with human cases of pneumonic plague
UK experience to date	Last outbreak in the UK was in 1918.
Risk rating	Exceptionally low to negligible
Recent cases or outbreaks	Between 1 January and 12 May 2024, the DRC reported, 354 suspected plague cases, including 8 deaths (CFR of 2.3%) from the province of Ituri. It was not stated if these cases were bubonic and/or pneumonic plague. Plague is endemic in Ituri Province.

Severe acute respiratory syndrome (SARS)

Geographical risk areas	Currently none. Two historical outbreaks originating from China in 2002 and 2004.
Sources and routes of infection	• airborne particles • direct contact with contaminated environment
UK experience to date	Four imported SARS cases related to the 2002 outbreak.
Risk rating	Exceptionally low to negligible
Recent cases or outbreaks	No confirmed or suspected human cases reported globally since 2004.

Question 4

Incidents of significance of additional HCIDs

Accepted Answer

Argentine haemorrhagic fever (Junin virus)

Geographical risk areas	All reported human infections have been acquired in China.
Sources and routes of infection	• close contact with infected birds or their environments • close contact with infected humans (no sustained human-to-human transmission)
UK experience to date	No known cases in the UK.
Risk rating	Very low (UKHSA risk assessment).
Recent cases or outbreaks	No confirmed or suspected human cases were reported in May 2024.

Bolivian haemorrhagic fever (Machupo virus)

Geographical risk areas	Bolivia – cases have been identified in the departments of Beni (Mamoré, Iténez and Yucuma provinces) and Cochabamba (Cercado province).
Sources and routes of infection	• direct contact with infected rodents • inhalation of infectious rodent fluids and excreta • person-to-person transmission has been documented
UK experience to date	No known cases in the UK.
Risk rating	Exceptionally low to negligible – travel-related cases have never been reported.
Recent cases or outbreaks	No confirmed or suspected human cases were reported in May 2024.

Lujo virus disease

Geographical risk areas	A single case acquired in Zambia led to a cluster in South Africa in 2008.
Sources and routes of infection	• presumed rodent contact (excreta, or materials contaminated with excreta of infected rodent) • person to person via body fluids
UK experience to date	No known cases in the UK.
Risk rating	Exceptionally low to negligible – a single travel-related case has been reported. No cases have been reported anywhere since 2008.
Recent cases or outbreaks	No cases have been reported anywhere since 2008.

Severe fever with thrombocytopenia syndrome (SFTS)

Geographical risk areas	Mainly reported from China (south-eastern), Japan and Korea. Cases have also been reported in Taiwan, Thailand, Myanmar and Vietnam. Serological evidence of SFTS in Pakistan.
Sources and routes of infection	• presumed to be tick exposure • person-to-person transmission described in household and hospital contacts, via contact with blood or bloodstained body fluids
UK experience to date	No known cases in the UK.
Risk rating	Exceptionally low to negligible – not known to have occurred in travellers.
Recent cases or outbreaks	According to media reports on 30 May 2024, so far this year, 12 cases of SFTS, including 3 deaths have been reported in South Korea

Andes virus (Hantavirus)

Geographical risk areas	Chile and Southern Argentina.
Sources and routes of infection	• rodent contact (excreta, or materials contaminated with excreta from an infected rodent) • person-to-person transmission described in household and hospital contacts
UK experience to date	No known cases in the UK.
Risk rating	Very low – rare cases in travellers have been reported.
Recent cases or outbreaks	No confirmed or suspected human cases were reported in May 2024.

Avian influenza A(H5N6) virus

Geographical risk areas	Mostly China. New strain reported in Greece in March 2017, and subsequently found in Western Europe in birds.
Sources and routes of infection	Close contact with infected birds or their environments.
UK experience to date	No known cases in the UK.
Risk rating	Very low – not known to have occurred in travellers (UKHSA risk assessment).
Recent cases or outbreaks	During May 2024, one fatal human case of avian influenza A(H5N6) was reported from Fujian Province, China. The case had exposure to backyard poultry prior to symptom onset. This is the first human case of avian influenza A(H5N6) reported in China for 2024.

Avian influenza A(H7N7) virus

Geographical risk areas	Sporadic occurrence in birds across mainland Europe and the UK. A human case was reported in Ireland in 1996, 89 cases were reported in the Netherlands in 2003, and 3 human cases were reported in Italy in 2013.
Sources and routes of infection	• close contact with infected birds or their environments • close contact with infected humans (no sustained human-to-human transmission reported)
UK experience to date	No known cases in the UK.
Risk rating	Very low – human cases are rare, and severe disease even rarer.
Recent cases or outbreaks	No confirmed or suspected human cases were reported in May 2024.

Question 5

Authors of this report

Accepted Answer

Emerging Infections and Zoonoses Team, UKHSA

Global high consequence infectious disease events: summary May 2024