Research and analysis

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

Updated 23 May 2024

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

Notable incidents of public health significance

Summary of incidents

Disease or infection Location New or update since the last report
Nipah virus disease Bangladesh New
Cholera Southern Africa region New

Nipah virus disease (NiVD) – Bangladesh

Event summary

In Bangladesh, 2 fatal cases of Nipah virus infection were confirmed in January 2024. Both cases were residents of the Dhaka division of Bangladesh and were not known to be epidemiologically linked. The cases both had a history of consuming raw date palm sap prior to the onset of symptoms. No further cases were identified among contacts of the confirmed cases.

The first case was a 38 year old male from Manikganj district, who became symptomatic on 11 January 2024 and was hospitalized on 16 January 2024. On 21 January 2024, samples from the case tested positive for Nipah virus via reverse transcription polymerase chain reaction (RT-PCR) and by enzyme-linked immunosorbent assay (ELISA) testing. This case died on 28 January 2024.

The second case was a 3 year old female from Shariatpur district. She became symptomatic on 28 January 2024 and was hospitalised on 30 January 2024, where she died the following day. On 31 January 2024, samples collected from the case tested positive for Nipah virus via RT-PCR and ELISA testing.

A response was implemented by the Government of Bangladesh, with support from the World Health Organization (WHO). Response measures implemented included national awareness and health education activities, engagement and sensitization of One Health partners, strengthening of surveillance, infection prevention and control, diagnosis and management of patients, and risk communication.

Figure 1. Number of cases of Nipah virus disease and deaths by year, 1 January 2001 to 9 February 2024, Bangladesh. Adapted from the World Health Organization’s Disease Outbreak News report (accessed: 18 February 2024).

Incident assessment

In Bangladesh, Nipah virus infections are reported annually, typically occurring between December and April, coinciding with the gathering and consumption of date palm sap. Bangladesh has robust public health measures to identify and control NiVD outbreaks.

On 27 February 2024, the WHO assessed the risk of NiVD in Bangladesh at the national level as moderate. This was due to the high case fatality rate (CFR) from NiVD and the lack of specific drugs and vaccines available for this infection. Additionally, there is continued consumption of raw date palm sap by the community, despite ongoing community engagement and risk communication efforts.

To date, there have been no reported cases of Nipah virus in the UK. While severe disease in a case is possible, transmission within the wider UK population is highly unlikely as there are established processes for the isolation and contact management of high consequence infectious diseases (HCID) cases. For HCIDs, a range of effective clinical, public health, and infection prevention and control strategies are available, which can be modified as needed.

Cholera – Zambia and Zimbabwe

Event summary

Zambia and Zimbabwe have experienced significant surges in cholera cases since October 2023. The increase in cases coincides with the rainy season that result in floods and landslides, and thus the contamination of drinking water.

In Zambia, from 1 to 28 January 2024, 15,589 cholera cases and 584 deaths (CFR of 3.7%) have been reported. Nationally, the cholera outbreak has affected 9 of 10 provinces and a total of 61 districts. The main drivers of the outbreak are the poor water and sanitary conditions in densely populated urban and peri-urban areas, as well as localized floods caused by rains which contaminated water sources in the same areas.

In Zimbabwe, the cholera outbreak started on 12 February 2023 in Chegutu town. From 12 February 2023 to 28 January 2024, 21,230 cholera cases and 476 deaths (CFR of 2.2%) have been reported. The 3 most affected provinces are Harare (9,010), Manicaland (5,748) and Masvingo (2,422), accounting for 80.9% of total cases. 62 districts have reported at least one case of cholera.

Incident assessment

Cholera is an acute diarrhoeal illness spread by the consumption of food and water contaminated with Vibrio cholerae. Globally, countries experiencing natural disasters, poverty, and reduced access to clean drinking water are at increased risk of cholera outbreaks.

Even though numerous cholera outbreaks have been documented globally, only a small number of cases are recorded annually among travellers returning to the UK. In 2023, there were 17 confirmed cases of cholera in UK travellers. The risk of a cholera outbreak in the UK is extremely low due to high standard sanitary infrastructure and hygiene practices.

The WHO classify the global resurgence of cholera as a grade 3 emergency, and continue to assess the risk of cholera at a global level as very high. This is due to the depletion of stocks of cholera vaccines and treatments, global expansion and a large number of outbreaks currently being reported.

Other incidents of interest

Summary of other incidents

Disease or infection Location
Anthrax Multi-country
Dengue Brazil
Influenza A(H1N1)v Spain
Measles Multi-country
Rift Valley fever Kenya
Western equine encephalitis Argentina
Yellow fever South Sudan
Zika virus Multi-country

Anthrax

In Uganda, the WHO Regional Office for Africa reported that an outbreak of anthrax in humans has affected Ibanda, Kazo, Kween, Kyotera and Lwengo districts. Since the outbreak began on 3 August 2023, and as of 5 January 2024, 88 cases (including 22 confirmed) and 11 deaths (CFR of 12.5%) have been reported.

In Zimbabwe, media sources reported an increase in the number of human anthrax cases in the Midlands Province. Case numbers and details of diagnostic testing were not provided. Media reports that more than 40,000 cattle have been vaccinated against anthrax to help control the spread of the disease.

Dengue

In Brazil, as of epidemiological week 4, Brazil’s Ministry of Health has reported 134,367 probable dengue cases, 102 confirmed deaths and 33 deaths under investigation nationally. Whilst Minas Gerais state has reported the most cases (55,315 probable cases), the Federal District has the highest incidence rate at 680.7 cases per 100,000 population (19,175 cases). In 2023, for the same period, Brazil reported 20,622 probable cases.

Influenza A(H1N1)v

On 29 January 2024, Spanish authorities reported a possible human infection with swine influenza A(H1N1) variant virus from the Catalonia Region. The case is a 33 year old male, with no history of underlying conditions, who works on a pig farm. The case became symptomatic on 25 November 2023. The individual fully recovered, and no further cases were detected among contacts, nor among co-workers on the pig farm.

Measles

In Afghanistan, as of 27 January 2024, a total of 2,757 suspected measles cases and 7 deaths (CFR of 0.3%) were reported. Among suspected measles cases, 2,210 (80.2%) were children under 5. According to WHO, an increase in the number of measles cases has been observed since epidemiological week 47 of 2023 and has been attributed to low immunisation coverage.

In the United Kingdom, since 1 October 2023 and as of 30 January 2024, 347 laboratory confirmed measles cases were reported in England. The number of reported measles cases has been increasing since October 2023. In January 2024 alone, 127 confirmed cases were reported. In England, the majority of confirmed cases (75%; 260 cases) were reported in the West Midlands region. 67% of the total cases (233/347) were in children under the age of 10.

Rift Valley fever

In Kenya, from 9 to 19 January 2024, 12 suspected and one confirmed case of Rift Valley fever were reported in Marsabit County. The WHO states that this coincided with reports of animal deaths in Marsabit and Wajir counties.

Western equine encephalitis (WEE)

In Argentina, 279 human cases of WEE (223 suspected and 56 confirmed cases) have been reported in 15 provinces between 20 December 2023 and 27 January 2024. According to the WHO, the first human case of WEE in Argentina since 1996 was reported in the province of Santa Fe on 20 December 2023.

Yellow fever

In South Sudan, on 24 December 2023, the Ministry of Health released a statement confirming a yellow fever outbreak in Western Equatoria state. According to the Africa CDC, between 7 December 2023 and 29 January 2024, 29 suspected and one confirmed case of yellow fever, including 5 deaths have been reported in Western Equatoria state. All cases were reported from 5 counties, including Yambio (15 cases), Tambura (7 cases), Nzara (5 cases), Ibba (2 cases) and Ezo (one case). The Ministry of Health activated a Public Health Emergency Operation Centre to coordinate a response, field investigations and active case searching alongside a team of experts and WHO colleagues.

Zika virus

According to the Pan American Health Organization, in 2024, as of epidemiological week 4, 2,009 Zika virus cases (including 195 confirmed cases) were reported in the Region of the Americas. Brazil reported the most cases (1,924 cases). For comparison, in the same 2023 period, 4,119 Zika virus cases (including 454 confirmed cases) were reported. On 6 January 2024, media reported that 18 suspected (4 confirmed) cases of congenital syndrome associated with Zika virus infections were registered in Acre Province, Brazil between 2015 and 2023.

Thailand reported an increase in Zika virus infections in 2023, with 758 cases reported. On 26 January 2024, the European Centre for Disease Prevention and Control reported that 23 Zika virus infection cases with exposure in Thailand had been reported from 5 European Union countries. The cases all had disease onset, notification, or exposure in 2023, and were reported from Germany (10 cases), France (9 cases), Portugal (2 cases), Ireland (one case) and Belgium (one case).

Publications of interest

Chapare virus

A recently published review aimed to identify and summarise evidence relating to the epidemiology of Chapare virus. A total of 10 documented cases were identified, all of which originated in Bolivia. At least 5 cases were suspected to have acquired the infection following exposure to infected rodents or rodent excrement (all were agricultural workers or farmers), while a further 4 cases were suspected to have been infected via human-to-human transmission. The study noted that there is limited research on the epidemiology of Chapare haemorrhagic fever.

Cholera

A global shortage of oral cholera vaccines led to the International Coordinating Group temporarily suspending the standard 2-dose vaccine regimen, and an adoption of a single-dose approach, in October 2022. A matched case-control study aimed to estimate the effectiveness of a single-dose of the oral cholera vaccine Euvichol-Plus in a high-burden setting in the Democratic Republic of the Congo (DRC). The study found that a single dose of Euvichol-Plus provided substantial protection against medically attended cholera for at least 36 months after vaccination in this cholera-endemic setting. The study reported that protection in children under 5 years might wane significantly during the third year after vaccination.

Clade I monkeypox virus (MPXV)

In November 2023, the WHO reported the first known cases of sexual transmission of Clade I MPXV, when a resident of Belgium, with connections to the DRC, tested positive for Clade I MPXV in Kenge, Kwango Province, during a visit to the DRC. In January 2024, a letter written by several health professionals in Belgium reported that based on surveillance data and retesting of stored samples, there is no evidence of Clade I MPXV circulating in Belgium.

Lassa fever

A recent animal study showed a diminished ability of human monoclonal antibodies (Arevirumab-3) to protect cynomolgus macaques against a new lineage (VII) of Lassa fever virus strains. The strains have been detected in Benin and Togo.

Severe fever with thrombocytopenia syndrome (SFTS)

SFTS is caused by the SFTS virus (SFTSV). The primary mode of transmission occurs when humans are bitten by infected ticks, with human-to-human transmission of SFTSV also reported. In a recent study, the authors report on the potential zoonotic transmission of SFTSV from domesticated camels to humans in China, suggesting camels as a potential competent reservoir.

Zika virus

Current scientific evidence shows that antigenic relationships between flaviviruses produce immune responses that are cross-reactive. A study published in January 2024, reported that dengue infected individuals with prior Japanese encephalitis virus infection produced neutralizing human monoclonal antibodies reactive to Zika virus.

Novel pathogens and diseases

Variovorax durovernensis

A recently published case study reports the first human infection with a novel Variovorax species: Variovorax durovernensis. The organism was isolated from the prosthetic aortic graft of a shepherd and was identified via whole genome sequencing. This highlights the value of advanced diagnostic techniques in identifying and characterising novel organisms with unusual clinical presentations.

Lymphocytic choriomeningitis virus

Lymphocytic choriomeningitis virus (LCMV) is a rodent-borne arenavirus capable of causing encephalitis, meningitis and sudden infant death syndrome in humans. In a recent study, authors describe a novel lineage of LCMV, lineage V, in wood mice (Apodemus sylvaticus) from Germany.

Further reading

Circulating vaccine-derived type 2 poliomyelitis

Effectiveness of poliovirus vaccines against circulating vaccine-derived type 2 poliomyelitis in Nigeria between 2017 and 2022: a case-control study

Gonorrhoea

Novel strain of multidrug non-susceptible Neisseria gonorrhoeae in the USA

Lassa fever

Monoclonal antibody therapy demonstrates increased virulence of a lineage VII strain of Lassa virus in nonhuman primates

Mpox

Residual immunity from smallpox vaccination and possible protection from mpox, China

Tick-borne encephalitis

Tick-borne encephalitis, Lombardy, Italy

High consequence infectious diseases monthly summaries

National flu and COVID-19 surveillance reports

Avian influenza (influenza A H5N1): technical briefings

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

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

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

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

Authors of this report

This report was created by UKHSA’s Emerging Infections and Zoonoses team. You can contact us at epiintel@ukhsa.gov.uk