Research and analysis

Infectious disease surveillance and monitoring for animal and human health: summary June 2024

Updated 6 March 2025

1. Interpreting this report

The UK Health Security Agency’s (UKHSA) Emerging Infections and Zoonoses (EIZ) team uses an integrated horizon scanning approach, which combines information on both human and animal health, to identify and assess outbreaks and incidents of new and emerging infectious diseases globally. For further information about the EIZ team’s horizon scanning process, please see our Epidemic intelligence activities.

This summary provides an overview of incidents (new and updated) of public health significance, which are under close monitoring. The incidents are divided into 2 sections: Notable incidents of public health significance and Other incidents of interest. For each notable incident of public health significance, an incident assessment is provided, based on the EIZ team’s interpretation of the available information.

The report also includes a section that focuses on Novel pathogens and diseases and a final Publications of interest section, which contains new publications relevant to emerging infections.

Epidemiological updates for diseases classified as a high consequence infectious disease (HCID) are published in UKHSA’s HCID monthly summary, unless they are considered a notable incident of public health significance, in which case a more detailed summary will be provided in this report.

For more information, or to sign up to the distribution list to receive an email alert when new reports are published, please contact epiintel@ukhsa.gov.uk

2. Notable incidents of public health significance

2.1 Summary of incidents

Disease or infection	Location	New or update since the last report
Avian influenza A(H5)	multi-country	New
Mpox	Democratic Republic of the Congo	Update

2.2 Avian influenza A(H5) – United States

Event summary

On 7 June 2024, the World Health Organization (WHO) reported the first laboratory-confirmed human case of avian influenza A(H5N1) virus (Clade 2.3.2.1a) from Australia. The case, a 2-year-old female, had a travel history to Kolkata, India. On 25 February 2024, the case showed symptoms of fever, irritability and inappetence, and sought medical attention on 28 February 2024. The case returned to Australia on 1 March 2024 and was hospitalised on 2 March 2024. Respiratory samples were collected from the case on 6 and 7 March 2024, which tested positive for influenza A. Further analysis of the samples through genetic sequencing confirmed avian influenza A(H5N1) infection. The case had no known exposure to sick persons or animals while in India. The source of the infection is unknown.

In China, on 18 June 2024, the Hong Kong Centre for Health Protection reported one fatal human case of avian influenza A(H5N6). This is the second human case of avian influenza A(H5N6) reported from China in 2024. The case was a 41-year-old male from Fujian Province. The case’s symptom onset date and potential exposure are not stated in the report. Since 2014, and as of 15 June 2024, 91 human cases of avian influenza A(H5N6) have been reported in China.

On 5 June 2024, the WHO reported a fatal human case of avian influenza A(H5N2) in Mexico. This was the first human case of avian influenza A(H5N2) reported globally. The case was a 59-year-old resident who had multiple co-morbidities and no history of exposure to poultry or other infected animals. On 17 April 2024, the patient experienced fever, shortness of breath, diarrhoea, nausea, and general malaise. On 24 April 2024, the case sought medical attention, was hospitalised and died on the same day. On 22 May 2024, sequencing results of the case’s respiratory samples confirmed avian influenza A(H5N2) infection. No further cases were reported during the epidemiological investigation.

2.3 Incident assessment

Between 1 January 2003 and 7 June 2024, 893 human infections with avian influenza A(H5N1), including 463 deaths (case fatality rate (CFR) of 51.8%), have been reported globally. As of 28 June 2024, 92 human infections with avian influenza A(H5N6) including 40 deaths (CFR of 40%) have been recorded in the Western Pacific Region.

The WHO assesses the risk to the general population posed by avian influenza A(H5) viruses as low. Human infections are rare and mostly associated with exposure to infected animals or their contaminated environments. No evidence of sustained human-to-human transmission has previously been reported.

In the UK, to the end of June 2024, 5 human infections with avian influenza A(H5N1) have been reported. Currently, there are no indicators of increasing risk of avian influenza A(H5) to human health. The risk may be higher for those with exposure to potentially infected animals and or their contaminated environments.

2.4 Mpox – Democratic Republic of the Congo (DRC)

Event summary

On 16 December 2022, an mpox epidemic was declared in the DRC. Since then, a substantial increase in the number of suspected mpox cases and deaths has been observed nationally. To date, only clade I mpox virus (MPXV) has been reported in the DRC. Between 1 January and 16 June 2024, the DRC Ministry of Health reported 1,030 confirmed mpox cases, and 9,192 suspected cases, including 419 mpox deaths among suspected cases (CFR of 4.6%). These cases were reported in 23 out of 26 (88.5%) provinces in the DRC. Between February and June 2024, 6 new provinces have reported at least one suspected mpox case.

In April 2023, clade I MPXV transmission through sexual contact was reported for the first time in Kwango Province Genomic sequencing of MPXV samples collected between October 2023 and January 2024 revealed a novel variant of clade I MPXV in the Kamituga health zone, South Kivu Province, where sexual transmission was recorded, estimated to have emerged around mid-September 2023. This new variant, designated as clade Ib, predominantly exhibited APOBEC3-type mutations, suggesting viral adaptation due to sustained circulation among humans.

On 1 June 2024, the first mpox case in North Kivu Province was confirmed in Karisimbi health zone, Goma. The case presented with symptoms including a macular skin rash, difficulty swallowing, painful urination, headache, and genital sores. Epidemiological investigation revealed that the case had travel history to South Kivu Province and had sexual contact with a suspected mpox case. As of 16 June 2024, 8 confirmed cases have been reported in Nyiragongo and Karisimbi health zones.

2.5 Incident assessment

The WHO has classified the risk associated with mpox in the DRC as high. This assessment is based on several factors. The majority of cases and deaths have so far occurred among children in endemic regions, resulting in a significant impact on this vulnerable group. There has been a geographical spread of clade I MPXV across regions in the DRC. Clade Ib MPXV is reported being transmitted through sexual contact within key populations further accelerating its spread. The sustained transmission of clade Ib MPXV through sexual contact in North and South Kivu provinces poses a transmission risk to bordering countries such as Tanzania, Rwanda, Burundi and Uganda.

To date, there have been no cases of clade I MPXV reported in the UK, and this clade has not been implicated in the international mpox outbreak in non-endemic countries that started in mid-2022. In the UK, clade I MPXV is considered a high consequence infectious disease (HCID), for which there are established processes for the isolation and contact management of a HCID case. There are a range of robust public health, clinical, infection prevention and control measures available for HCIDs, which can be adapted for use, as necessary.

2.6 Summary of other incidents

Disease or infection	Location
Anthrax	multi-country
Arenavirus	multi-country
Avian influenza A(H9N2)	multi-country
Cholera	multi-country
Dengue	multi-country
Mpox (clade IIb)	South Africa
West Nile virus	Israel
Yellow fever	Bolivia
Zika virus	multi-country

2.7 Anthrax

On 10 June 2024, media reported 3 confirmed human anthrax cases in Zagatala district, Azerbaijan. The cases were hospitalised and are recovering. Possible exposures for the cases were not reported.

In Ethiopia, on 19 June 2024, media reported 17 human anthrax cases including 4 deaths in Hintalo, Southwest Tigray. According to the media report, the cases had consumed meat from an infected ox, which was slaughtered on 5 June 2024 and shared amongst 500 individuals across 30 households. Anthrax is endemic in Ethiopia.

2.8 Arenavirus

On 10 June 2024, the La Paz Department Health Service reported a laboratory confirmed case of arenavirus. According to the official report, the case is a 25-year-old male from Teoponte, La Paz Department, Bolivia, who was initially admitted to a private clinic and later transferred to a public hospital. The report does not state the symptoms of the case, nature of exposure, or details regarding case contacts. An international team of experts was deployed to the region to provide technical assistance and training to the local health teams. Although the report does not specify the type of arenavirus, outbreaks of Machupo and Chapare haemorrhagic fevers have previously been reported in Bolivia.

2.9 Avian influenza A(H9N2)

On 11 June 2024, the WHO reported a confirmed human case of avian influenza A(H9N2), in a 4-year-old child from West Bengal State, India. The case had a pre-existing respiratory condition and presented with fever and abdominal pain on 26 January 2024 and was later hospitalised. On 2 February 2024, the case tested positive for influenza B and adenovirus before being discharged on 28 February 2024. The case was re-admitted on 3 March 2024 after developing severe respiratory distress. Samples collected from the case tested positive for rhinovirus and unspecified influenza A virus on 5 March 2024, which was subsequently confirmed as avian influenza A(H9N2) on 26 April 2024. The case had exposure to backyard poultry. There were no reported symptoms from contacts in the family, wider neighbourhood or among healthcare workers in the medical facilities that the case had attended.

In China, 2 confirmed human cases of avian influenza A(H9N2) were registered from Anhui Province and Guangxi Autonomous Region. Both cases had mild illnesses and had previous exposure to a live poultry market. The latest case was reported from Guangxi Autonomous Region, with symptom onset date on 2 May 2024. Environmental samples associated with both cases tested positive for avian influenza A(H9). Close contacts of each case, including family members, tested negative for influenza.

2.10 Cholera

Between 1 January and 29 June 2024, the Africa Centres for Disease Control and Prevention reported 119,251 cholera cases (23,652 confirmed) and 1,836 deaths (CFR of 1.54%) across 16 African Union Member States. Most cases were reported in the DRC (20,143 cases, 298 deaths), Zambia (20,059 cases, 612 deaths) and Zimbabwe (19,409 cases, 385 deaths). In 2023, a total of 241,317 cholera cases and 3,827 deaths were recorded in 19 African Union Member States, with Malawi registering the highest case numbers (43,015 cases and 1,262 deaths) followed by the DRC. Data should be interpreted with caution due to differences in case definitions, laboratory capacities and reporting capabilities across African Region countries. The true burden of disease within these countries is likely an underestimation.

In Mayotte, as of 25 June 2024, 210 cholera cases (including 2 deaths) have been registered since the first case was reported on 18 March 2024. Of the total recorded cases, 189 cases were locally acquired, and 21 cases were imported. There has been an increasing trend in the number of reported cases with 4 ongoing outbreaks in Mamoudzou community.

In Nigeria, between epidemiological weeks 1 to 26 of 2024, 2,102 suspected cholera cases and 63 deaths (case fatality rate of 3.0%), have been reported. In Lagos state, an outbreak was declared on 9 June 2024. As of 30 June 2024, 1,038 cases and 38 deaths have been registered in Lagos state. Lagos state accounts for 49% of the total recorded cholera cases in Nigeria, so far in 2024.

On 26 June 2024, media reported that the cholera outbreak in Zimbabwe is at the point of being declared over, given the decreasing trend in cases in most provinces. Since the start of the outbreak in February 2023 and as of 24 June 2024, 34,547 suspected and 4,217 confirmed cholera cases have been recorded. The article reports 87 confirmed cholera deaths.

2.11 Dengue

In the Region of the Americas, the Pan American Health Organization (PAHO) has reported 9,386,082 dengue cases (including 4,630,669 confirmed cases) and 4,529 deaths between 1 January and 18 June 2024. This is a 103.29% increase in cases compared to the same period in 2023. The WHO states that the number of cases reported from January to June 2024 exceeds the maximum number of cases historically stated in a given year. Between epidemiological week 1 and 23, Brazil (7,866,769 cases), Argentina (504,580 cases) and Peru (249,843 cases) reported the most cases in the Americas Region. All 4 dengue serotypes are currently circulating.

In South Trinidad, Trinidad and Tobago, media confirmed the first dengue death since 2017. The report states that 126 laboratory confirmed cases have been reported since the start of 2024. In response to the incident, the Ministry of Health plans to conduct inspection of residential areas, and fumigation of large outdoor spaces where cases have been detected.

Several countries across Asia have been reporting an increase in dengue cases in recent months. According to WHO, 610 cases of dengue have been recorded in the Maldives during May 2024. This represents a 150% increase in cases compared to April 2024 (244 cases). Between January and May 2024, a total of 1,234 cases of dengue were recorded, compared to 1,219 cases during the same period in 2023.

In Thailand, as of 20 June 2024, 36,246 dengue cases and 37 deaths (CFR of 0.1%) have been reported. In comparison, 35,227 cases including 36 deaths were registered for the same period in 2023.

2.12 Mpox (clade IIb)

In South Africa, 16 laboratory confirmed cases of mpox have been reported since the start of the outbreak on 8 May 2024, up to 26 June 2024. Cases have been reported in KwaZulu-Natal (8 cases), Gauteng (7 cases) and Western Cape (one case).

All cases are males aged between 23 and 42-years-old. Of the 16 cases, 11 self-identified as men who have sex with men. These are the first reported mpox cases in South Africa since 2022.

In response to this outbreak, rapid response teams have been deployed to affected communities to support further investigations, contact tracing, case management, and risk communication. Available genomic sequencing results for 5 confirmed cases identified the clade IIb MPXV.) which is linked to the multi-country mpox outbreak.

2.13 West Nile virus (WNV)

On 29 June 2024, media reported that 81 WNV cases (including 64 hospitalisations) and 7 deaths have been recorded in Israel. The Israel Ministry of Health recommends using insect repellents, wearing protective clothing, and eliminating standing water around residential areas.

2.14 Yellow fever

On 18 June 2024, media reported a suspected case of arenavirus in a 19-year-old male from La Paz Department, Bolivia. However, on 19 June 2024, media reported that the individual had tested positive for yellow fever. The Bolivian Ministry of Health reported 2 deaths from yellow fever in April and May 2024. Both cases travelled to the northern part of La Paz Department.

2.15 Zika virus

According to PAHO, 24,582 Zika virus cases (8,493 confirmed) and 2 deaths were recorded in the Region of the Americas between epidemiological weeks 1 and 24 of 2024. Most cases have been reported from Brazil (24,171 cases) and Bolivia (168 cases).

In Thailand, the Ministry of Health reported 143 Zika virus cases (no deaths) across 26 provinces in 2024. Most cases have been registered in the Central Region (60 cases). The majority of cases are aged between 25 to 34 (26.6%) and 35 to 44 (25.2%) years.

3. Publications of interest

3.1 Viral haemorrhagic fevers (VHF)

Outbreaks of VHFs such as ebolavirus, Marburg virus and Lassa virus occur sporadically and can pose a considerable risk to human health. Multi-vectored vaccine platforms offer enhanced immunogenicity, broad-spectrum protection, and versatility, and are critical in improving health outcomes in low resource settings where there is higher prevalence of VHFs, limited healthcare resources and delayed response to outbreaks.

Authors in the study used 2 viral vectored vaccine platforms to develop a multi-pathogen vaccine regimen that induces immune responses against 4 viral pathogens. The study evaluated the protective effects conferred by the vaccines in lethal virus challenge models, demonstrating protection against ebolavirus, Marburg virus and Lassa virus challenges.

3.2 Mpox (clade II)

This study aimed to investigate the emergence and spread of clade IIb MPXV in Nigeria before the global outbreak in 2022 to 2023, acknowledging the significance of limited genomic data and the necessity to comprehend the timing and origin of the virus emergence. The authors in this study generated 112 MPXV genomes sampled from Nigeria during 2021 to 2023 to bridge the gap in understanding. They estimated that the lineage capable of human-to-human transmission emerged around July 2014 in Rivers State and circulated undetected until September 2017.

In another study, authors investigated the zoonotic transmission dynamics of MPXV in Cameroon and Nigeria, with a focus on the border regions between the countries. The authors reported that mpox cases primarily occur following zoonotic transmission of a newly identified Clade IIb.1 virus. The authors report 2 separate zoonotic lineages circulating across the Nigeria-Cameroon border, indicating recent and historical cross-border transmission. The findings suggest that the cross-border forest ecosystems likely host shared animal populations, which act as reservoirs facilitating the virus’s spread between the 2 countries.

3.3 Avian influenza A(H5N1)

This study described an investigation into an epizootic outbreak of highly pathogenic avian influenza A(H5N1) virus among dairy cattle on a farm in Texas, USA, during March and April 2024. The researchers used multiple detection techniques to examine swab specimens collected from 30 cattle (24 sick and 6 healthy animals). The authors reported that several cattle swab specimens demonstrated molecular evidence of avian influenza A(H5N1) virus. Phylogenetic analysis showed that the A/cattle/Texas/56283/2024 (H5N1) virus was highly similar to 13 other avian influenza A(H5N1) viruses isolated from poultry in the Texas epizootic, suggesting a single interconnected multi-species outbreak in the state. Furthermore, the avian influenza A(H5N1) virus was more prevalent in nasal swab samples compared to rectal swab samples, supporting the view that the respiratory tract in cattle may play a role in facilitating cow-to-cow transmission. The study highlights the need for a one-health approach in addressing complex multi-species outbreaks of emerging pathogens.

Another study aimed to investigate the persistence of avian influenza A(H5N1) and human influenza A(H1N1) viruses in unpasteurized milk on milking equipment. The study found that both viruses remained infectious in unpasteurized milk on milking equipment surfaces for up to 5 hours, which could pose a potential exposure risk.

A recent molecular study of avian influenza A(H5N1) clade 2.3.4.4b implicated in an ongoing dairy cattle outbreak identified a single viral mutation (T199) that improved viral binding to mammalian cell receptors, which may have implications for the host range and cell types infected by these viruses.

4. Novel pathogens and diseases

4.1 Emayella augustorita

Pasteurellaceae consist of a large family of Gram-negative bacteria, including genera Pasteurella, Actinobacillus, and Haemophilus. Pasteurellaceae are mainly specialised commensals and pathogens of vertebrates including mammals and birds. The authors of this study reported a novel bacterial genus and species of the family Pasteurellaceae, called Emayella augustorita, which was isolated from a patient in France diagnosed with an intestinal adenocarcinoma.

4.2 Statoviruses

A recent study reports the discovery and characterization of restviruses, which are genetically related to, but distinct from, a novel taxon of statoviruses. The viruses were identified by retrospective analysis of meta-transcriptomic data from respiratory samples of 5 patients in Beijing, China. The study states that the discovery of a previously unrecognised virus, restvirus, in patients with acute respiratory disease highlights the continuous emergence of respiratory pathogens in humans, and warrants further investigations to characterise its pathogenicity and clinical importance.

5. Further reading

5.1 Pasteurella bettyae

Pasteurella bettyae Infections in Men Who Have Sex with Men, France

5.2 Influenza A

Emergence of Eurasian Avian-Like Swine Influenza A (H1N1) virus in a child in Shandong Province, China

5.3 Dengue and Zika virus

Primary exposure to Zika virus is linked with increased risk of symptomatic dengue virus infection with serotypes 2, 3, and 4, but not 1

5.4 Ebola virus disease

Serological evidence of zoonotic filovirus exposure among bushmeat hunters in Guinea

6. Related resources

1. High consequence infectious diseases monthly summaries

2. National flu and COVID-19 surveillance reports

3. Avian influenza (influenza A H5N1): technical briefings

4. Avian influenza (bird flu) in Europe, Russia and the UK reports

5. Bird flu (avian influenza): latest situation in England updates

6. Human Animal Infections and Risk Surveillance (HAIRS) group risk assessments and statements

7. Animal and Plant Health Agency (APHA) monitoring of disease in livestock and poultry monthly reports

7. Authors of this report

UKHSA’s Emerging Infections and Zoonoses team: epiintel@ukhsa.gov.uk