Research and analysis

Infectious disease surveillance and monitoring for animal and human health: summary November 2023

Updated 1 August 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.

For more information, or to sign up to the distribution list to receive an email alert when new reports are published, please contact [email protected]

Notable incidents of public health significance

Summary of incidents

Disease or infection	Location	New or update since the last report
Avian influenza A(H5N1)	Cambodia	Update
Influenza A(H1N2)v	United Kingdom	New
Mpox (monkeypox) (Clade I)	Democratic Republic of the Congo	New
Respiratory illness	China	New

Avian influenza A(H5N1) – Cambodia

Event summary

In November 2023, the Cambodian Ministry of Health reported 2 confirmed cases of avian influenza A(H5N1), in a village in Kampot Province. The first case, reported on 24 November 2023, was a female aged 21 years. The case had symptom onset on 19 November 2023 and was admitted to hospital on 23 November to the intensive care unit, where she subsequently died on 26 November 2023. The second case was reported on 25 November 2023, in a female aged 4 years. The case, a neighbour of the first case, was detected through active surveillance as part of the response following the detection of the initial case. Both cases had exposure to sick or deceased poultry prior to symptom onset. Samples collected from poultry in the village tested positive for avian influenza A(H5N1).

Phylogenetic analysis has shown the viruses fall within H5 clade 2.3.2.1c with close similarity to the viruses circulating in Cambodia and Southeast Asia since 2013 to 2014. The sequences are most similar to those from the 2 human cases reported in October 2023.

So far in 2023, 6 confirmed cases of avian influenza A(H5N1) clade 2.3.2.1c (including 4 deaths) have been reported in Cambodia. Cambodia has reported 62 human infections of avian influenza A(H5N1), including 41 deaths, since 2003.

Incident assessment

Globally, from January 2003 to 27 November 2023, 882 cases of human infection with avian influenza A(H5N1) virus were reported from 23 countries. Of these, 461 were fatal (case fatality rate (CFR) of 52%). Whenever avian influenza viruses are circulating in poultry, there is a risk of sporadic infection or small clusters of human cases due to exposure to infected poultry or contaminated environments. However, sustained human-to-human transmission has not been observed.

In total, 5 avian influenza A(H5N1) cases have been reported in the UK to date (3 cases in England and 2 cases in Scotland). Currently, the risk of avian influenza A(H5N1) infection to UK residents is considered very low. The risk of avian influenza A(H5N1) infection to UK residents who are travelling to affected areas is very low, but may be higher for those with exposure to potentially infected poultry and/or their contaminated environments. For further information, see the UKHSA’s risk assessment of avian influenza A(H5N1).

Influenza A(H1N2)v – United Kingdom

Event summary

On 27 November 2023, the UKHSA reported a confirmed case of influenza A(H1N2)v, the first detection of this strain in a human in the UK. The case was identified through routine national flu surveillance undertaken by UKHSA and the Royal College of General Practitioners. The case, a male aged over 75 years old residing in England, was tested by their General Practitioner after experiencing mild respiratory symptoms. The case has fully recovered. No further cases were detected during contact follow-up.

The influenza A(H1N2)v virus belongs to the swine influenza virus genetic clade 1B.1.1. Although the virus was similar to those detected in pigs in England, no direct contact between the case and any animal was reported.

Incident assessment

Sporadic human infections with swine influenza have been reported globally, usually following direct or indirect exposure to pigs or contaminated environments. Since 2005, a total of 50 human cases of influenza A(H1N2)v have been reported globally. Current evidence suggests that these viruses have not acquired the ability to sustain transmission among humans.

Clade 1B.1.1 is endemic in pigs in Great Britain and likely to be the dominant virus circulating. The general population has a very low risk of exposure to this virus. Those directly exposed to pigs regularly (for example, through occupation) may have a higher risk of exposure to this virus. On 27 November 2023, the Department for Environment, Food and Rural Affairs; the Animal and Plant Health Agency; and UKHSA updated guidance on how to spot swine influenza, what to do to prevent it and control its spread. UKHSA monitors influenza at the human/animal interface through targeted surveillance. No other cases have been detected through UKHSA’s enhanced community surveillance.

Mpox (monkeypox) (Clade I) – Democratic Republic of the Congo

Event summary

The first ever cases of sexually transmitted Clade I mpox (monkeypox) virus (MPXV) were reported from the Democratic Republic of the Congo (DRC). The first known case is a male resident of Belgium with connections to the DRC, who arrived in Kinshasa, on 15 March 2023 and started experiencing anal itching and discomfort the same day. On 16 March 2023, he travelled to the town of Kenge in Kwango Province. On 23 March 2023, he consulted a doctor who then took samples for testing on 24 March 2023. On 10 April 2023, the DRC Ministry of Health was notified of the confirmed mpox case from Kwango Province. Genomic sequencing of the sample confirmed that it was Clade I MPXV, similar to other strains circulating in the DRC. Although the case had no reported exposure to another person with confirmed mpox prior to infection, based on the epidemiological investigation the World Health Organisation (WHO) states that exposure to mpox likely occurred in Belgium.

While travelling in the DRC, the individual reported sexual contact with gay, bisexual, and other men who have sex with men. Among 27 contacts identified and 6 tested, 5 sexual contacts (4 male and one female) tested positive for Clade I MPXV.

Between 1 January and 12 November 2023, 22 out of 26 (85%) provinces in the DRC have reported 714 confirmed mpox cases, and 11,855 suspected cases, including 581 mpox deaths among suspected cases (CFR of 4.6%). This is the highest number of annual cases ever reported, with new cases identified in geographic areas that have not previously reported mpox, including Kinshasa, Lualaba, and South Kivu.

Figure 1. Geographical distribution of mpox (Clade I) suspected (a) and confirmed (b) cases in the Democratic Republic of Congo, between 1 January and 4 November 2023.

Adapted from the World Health Organization. Accessed: 14 November 2023.

Darker shades represent a higher number of cases, lighter shades represent a lower number of cases. Grey shades represent no reported suspected (a) or confirmed (b) cases between 1 January and 4 November 2023.

Incident assessment

WHO states that these are the first reported cases of mpox due to Clade I MPXV linked to sexual contact, and include a history of international travel within and across WHO regions. The introduction of Clade I MPXV in different sexual networks could facilitate and amplify the spread of this historically more virulent clade of the virus.

11 of the 26 provinces of the DRC are identified as endemic for mpox, but in more recent years the total number of mpox cases and the number of provinces reporting mpox has been expanding, to 22 provinces as of November 2023. It is still unclear what proportion of mpox cases in the DRC may be exposed through sexual contact; however, with outbreaks linked to sexual transmission documented in 2023 in 3 previously unaffected provinces, the potential additional public health impact of this new finding could be significant, particularly in under-resourced urban areas.

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. There are established processes for the isolation and contact management of high consequence infectious diseases (HCID) cases in the UK. 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. Therefore, risk to the UK is considered very low.

Respiratory illness – China

Event summary

On 21 November 2023, ProMED reported clusters of undiagnosed pneumonia in children’s hospitals in Beijing, Liaoning, and other unspecified places in China. A meeting between WHO and Chinese health authorities on 23 November 2023 confirmed an increase in Mycoplasma pneumoniae infections in children since May, and respiratory syncytial virus, adenovirus and influenza virus infections in children since October. There were no reports of any unusual or novel pathogens or unusual clinical presentations. Increases in respiratory illnesses were reported earlier in the season than previously experienced, but were not unexpected given the recent lifting of COVID-19 restrictions.

Increasing cases of M. pneumonia, predominately in children and adolescents, have been reported in at least 6 European Union and European Economic Area (EU/EEA) countries during the 2023/24 season.

Incident assessment

M. pneumoniae is a common respiratory pathogen and a common cause of paediatric pneumonia. Most cases are mild and recover without treatment, but it is treatable with antibiotics in severe cases. In China, since mid-October, additional enhanced surveillance of respiratory illnesses has been implemented, including, for the first time, M. pneumoniae. This complements existing respiratory surveillance mechanisms and may have contributed to the observed increase in detection and reporting of respiratory illness in children. There is limited detailed information available to fully characterize the overall risk of these reported cases of respiratory illness in children. However, due to the arrival of the winter season, the increasing trend in respiratory illnesses is expected.

M. pneumoniae epidemics typically occur cyclically in the UK every 3 to 4 years; the most recent previous epidemic peak was in winter 2019 to 2020.

Other incidents of interest

Summary of other incidents

Disease/infection	Location
Anthrax	multi-country
Avian influenza A(H9N2)	China
Chikungunya	Burkina Faso
Cholera	multi-country
Crimean-Congo haemorrhagic fever	multi-country
Dengue	multi-country
Diphtheria	multi-country
Hantavirus	multi-country
Mpox	multi-country
Plague	Madagascar
Polio	multi-country
Severe fever with thrombocytopenia syndrome (SFTS)	South Korea
West Nile virus	multi-country
Yellow fever	African region
Zika virus	multi-country

Anthrax

On 12 November 2023, media reported that the Department of Health in Cordillera had declared an anthrax outbreak in Kalinga, Philippines. Following the first reported case on 2 October 2023, a total of 5 cases, including one laboratory-confirmed and 4 suspected were reported, all of which reportedly prepared and consumed meat from a dead buffalo; all 5 cases have recovered. The last reported anthrax case in the region was in Abra in 2020.

On 26 November 2023, the Africa Centres for Disease Control and Prevention (Africa CDC) reported that the Ugandan Ministry of Health had confirmed an outbreak of anthrax in Kabira Sub-county, Kyotera District in Central Uganda. In total, 32 suspected and 6 confirmed cases were reported across Kween (5 cases) and Kyotera (33 cases, 16 suspected deaths) districts.

On 1 November 2023, the WHO was notified of a cutaneous anthrax outbreak in Zambia. During 2023, up to 26 November 2023, 588 suspected and 25 confirmed anthrax cases, and 4 associated deaths have been reported across 9 out of the 10 provinces in Zambia. The Zambian Ministry of Health have implemented public health measures such as training on disease identification and management, enhanced event-based surveillance, personal protective equipment, community engagement, and ongoing monitoring and clinical evaluation of discharged patients.

In Zimbabwe, as of 17 November 2023, the Africa CDC have reported 384 suspected cases of cutaneous anthrax from one of 10 provinces. The WHO report control measures have been established, in addition to disease surveillance for the early detection of cases.

Avian influenza A(H9N2)

Between 10 and 16 November 2023, one new human case of avian influenza A(H9N2) was reported to the WHO from Guangan city, Sichuan Province, China to the WHO. The case had a symptom onset date of 1 October 2023. In total, 92 cases of human infection with avian influenza A(H9N2), including 2 deaths, have been reported from the Western Pacific Region since December 2015, of which 90 were from China and 2 were from Cambodia.

Chikungunya

Between September and 17 November 2023, the Africa CDC have reported 235 suspected and 238 confirmed cases of chikungunya in Burkina Faso. The first case was confirmed on 6 September 2023 from Pouytenga health district, through Burkina Faso’s sentinel surveillance for arboviruses. Most confirmed cases have been reported from this health district (221 cases).

Cholera

In 2023, as of 15 November, over 610,000 cholera cases and 3,500 cholera deaths (CFR of 0.6%) have been reported globally from 29 countries. WHO states that the overall capacity to respond to multiple and simultaneous outbreaks remains strained due to a global lack of resources, including shortages of the oral cholera vaccine and supplies, as well as overstretched public health and medical personnel. The WHO continues to assess the risk of cholera at global level as very high.

The WHO African Region remains the most affected region, with 16 countries reporting cholera cases in 2023. In Southeast Africa, several countries have entered their rainy season (typically from October to April), with an increased risk of cholera transmission during this period. 

As of 15 November 2023, the countries reporting the most cases include:

• Afghanistan (203,911 cases, 93 deaths)

• Syria (161,620 cases, 7 deaths)

• Haiti (71,270 cases, 922 deaths)

• Malawi (59,088 cases, 1,769 deaths)

• DRC (43,643 cases, 390 deaths)

In Ethiopia, according to UNICEF, 27,900 cholera cases and 397 associated deaths have been reported nationally as of 26 November 2023. Media report that a 12% increase in the number of cholera deaths was reported during November compared to October, increasing the CFR from 1.37% at the start of November to 1.43% at the end of November. Of the 295 districts reporting cholera cases since the start of the outbreak in August 2022, 198 districts have been able to control the outbreak.

In Zimbabwe, on 17 November 2023, the International Federation of Red Cross and Red Crescent Societies reported that a state of emergency had been declared in Harare, the capital of Zimbabwe, in response to increasing cholera cases. As of 25 November 2023, 9,078 suspected and 1,337 confirmed cholera cases have been reported across 10 provinces in Zimbabwe, with 53 deaths reported among confirmed cases and a further 156 deaths among suspected cases, according to media reports.

Crimean-Congo haemorrhagic fever (CCHF)

CCHF is endemic in Africa, the Balkans, the Middle East and western and south-central Asia. The WHO Eastern Mediterranean Region remains the most affected region, reporting the highest number of cases.

Between 1 January and 25 November 2023, the WHO reported 1,226 CCHF cases, including 114 deaths (CFR of 9.3%) from Afghanistan. In 2022, Afghanistan reported 286 suspected and 103 confirmed CCHF cases, including 15 deaths.

On 29 November 2023, media reported that there had been 19 CCHF cases and 4 deaths (in Arabic) reported from Diyala Governate, Iraq, in 2023.

On 8 November 2023, media reported there had been 200 CCHF cases, of which 73 cases had been confirmed, and 20 associated deaths identified in Balochistan Province in Pakistan, in 2023.

Dengue

Save the Children have reported at least 5 million dengue cases and over 5,500 associated deaths across 20 countries between January and November 2023. This represents a 30% increase in cases compared to all of 2022 and an 18% increase in cases compared to 2019, and is the highest number of annual cases to be reported over the past 5 years.

Between 1 January and 30 November 2023, the government of Bangladesh reported 311,891 dengue cases, including 1,622 associated deaths (in Bangla and English) (CFR of 0.5%), with 107,836 cases (34.6%), including 937 deaths (57.8%) reported from Dhaka City. This represents the highest number of annual reported cases in the last 5 years. To compare, 62,382 dengue cases were reported in 2022.

Since the beginning of 2023, up to 24 November 2023, 202,451 dengue cases, of which 20,785 are confirmed, and 552 deaths, have been reported in 14 Africa Union Member States. Burkina Faso reported the most cases with 176,841 cases (including 17,125 confirmed cases), and 511 deaths across all 13 regions in the country. Ethiopia reported 16,693 cases, including 127 confirmed cases, and 15 deaths across 4 regions; 97% of cases were reported from the Afar Region.

Media reported on 9 November 2023, that 23,387 cases of dengue (in Spanish) had been reported nationally in Ecuador during 2023, a 42% increase compared 2022 (16,402 cases). This represents the highest number of cases reported in the past 7 years. Manabi Province has reported the most cases (6,649 cases).

On 28 November 2023, French Polynesia reported an autochthonous case of dengue serotype 2 (in French), in a resident of Papeete. Dengue cases have not been reported in French Polynesia for 3 years, although the mosquitoes that can carry the disease are present.

Media report that Guatemala has experienced an increase in dengue associated deaths with 89 dengue deaths reported in 2023 (in Spanish) as of 11 November 2023, an increase from 16 deaths reported in 2022. In total, during 2023, 57,628 dengue cases (including 126 severe cases) have been reported nationally.

As of 27 November 2023, Italy’s Higher Institute of Health have reported 82 autochthonous dengue cases (in Italian) so far in 2023. This is an increase in autochthonous dengue cases in Italy, following their last report of 10 cases in the Veneto region during August 2020.

Following the declaration of a dengue outbreak in Jamaica in September 2023, 3,147 dengue cases and 9 associated deaths have been reported as of 6 November 2023, according to media reports. All 4 dengue strains are reported to be circulating, however dengue serotype 2 has been identified as the dominant strain during the current outbreak. The last dengue epidemic in Jamaica occurred in 2019.

On 14 November 2023, media reported a dengue outbreak in Turks and Caicos following the detection of the first dengue case of 2023, on 17 October. Since then, 74 suspected dengue cases and 13 confirmed cases have been reported. Of the confirmed cases, 12 cases have been reported in Providenciales and one case has been reported in Grand Turk, with testing identifying dengue serotypes 2 and 3. This is a large increase in comparison to the 3 dengue cases reported in 2022. The Ministry of Health and Human Services through the Vector Control Unit of the Environmental Health Department have increased vector control activities.

Diphtheria

In 2023, as of 24 November, 6 African Union Member States (Algeria, Guinea, Mauritania, Niger, Nigeria, and South Africa) have cumulatively reported 22,503 diphtheria cases (of which 12,026 are confirmed), including 750 deaths (CFR of 6.2%).  85% of the cases were reported from Nigeria.

Since the beginning of 2023, up to 7 November, the European Centre for Disease Prevention and Control (ECDC) have reported 119 cases of diphtheria, including 2 deaths in the EU/EEA. Cases and deaths were reported from Germany (79 cases), the Netherlands (14 cases), Belgium (6 cases, one death), Czechia (6 cases), Latvia (3 cases, one death), Slovenia (3 cases), Norway (3 cases), Luxembourg (2 cases), and one case each in Slovakia, Spain, and Sweden. Among the 119 cases of diphtheria reported in 2023, 39 cases were classified as imported. In 2022, 356 cases of diphtheria, including 5 deaths, were reported in the EU/EEA.

Hantavirus

On 3 November 2023, media reported that there had been 19 hantavirus cases detected in Salta Province (in Spanish), Argentina, in 2023. On 2 November 2023, media reported that 15 cases of hantavirus had been identified in Hipolito Irigoyen, Misiones Province (in Spanish), in 2023. Although the type of hantavirus was not specified in either report, cases of Andes hantavirus had previously been detected in both provinces.

On 13 November 2023, media reported a fatal confirmed case of hantavirus in a 34-year-old (in Spanish) in the Metropolitan Region of Chile. The case had exposure to mouse excrement and developed symptoms on 6 November 2023. He was admitted to hospital on 10 November 2023, where he subsequently died. The type of hantavirus was not specified.

Mpox

Between 1 January 2022 and 30 November 2023, a total of 92,783 confirmed mpox cases, including 171 deaths, have been reported in all 6 WHO Regions. 906 new cases were reported in November 2023, a 26% increase compared to October 2023 (668 cases). During November 2023, 18 countries reported an increase in cases, with most reported from the Region of the Americas and from the European Region. As of 30 November 2023, the United States of America (USA) (31,070 cases), Brazil (10,967 cases), and Spain (7,684 cases) have reported the highest cumulative number of mpox cases.

Within the African Region, as of 17 November 2023, 11,020 mpox cases (811 confirmed, 10,209 suspected) and 557 deaths have been reported in 7 endemic countries so far in 2023. The countries reporting the highest number of cases include the DRC, Cameroon, and Nigeria. 

As of 30 November 2023, a total of 135 cases of mpox were reported in the UK during 2023. Of these, 130 were reported in England, 2 in Scotland, one in Wales, 2 in Northern Ireland, and one in Wales.

On 7 November 2023, Taiwan’s Centers for Disease Control reported the country’s first mpox associated death (in Chinese) in an unvaccinated male who was co-infected with HIV.

Plague

In Madagascar, on 18 November 2023, media reported 11 suspected cases of pneumonic plague including 8 deaths (in French), from several villages in Ankazovelo in the Atsimo-Atsinanana Region. Plague is endemic in the Ankazovelo area of Madagascar.

Polio

Wild polio virus type 1 (WPV1)

Between 1 January and 28 November 2023, 11 cases of WPV1 were reported to the Global Polio Eradication Initiative from Afghanistan (6 cases) and Pakistan (5 cases). This is a decrease from 30 cases reported in the equivalent 2022 period. WPV1 is endemic in Afghanistan and Pakistan.

Circulating vaccine derived polio virus (cVDPV)

In 2023, as of 28 November 2023, 109 cases of cVDPV1 have been reported from 3 countries: the DRC (83 cases), Madagascar (23 cases) and Mozambique (3 cases). This is a decrease from 191 cases reported during the same period in 2022.

In 2023, as of 28 November 2023, 265 cVDPV2 cases were reported across 17 countries, with the DRC (108 cases), Chad (44 cases), and Nigeria (43 cases) reporting the most cases. To compare, 658 cases were reported during 2022.

Severe fever with thrombocytopenia syndrome (SFTS)

Between week 1 and 45 (up to 12 November) of 2023, the Korean Disease Control and Prevention Agency reported 195 SFTS cases, including 37 associated deaths (in Korean). This is comparable to the equivalent 2022 period (188 cases, including 33 deaths). The Gyeonggi Region reported the most cases (31 cases), followed by Gangwon (28 cases).

West Nile virus (WNV) 

In the 2023 transmission season and as of 29 November 2023, EU/EEA countries have reported 707 human cases of WNV, including 67 deaths. Cases and deaths were reported from Italy (336 cases, 29 deaths), Greece (162 cases, 23 deaths), Romania (103 cases, 12 deaths), France (43 cases), Hungary (29 cases), Spain (17 cases, 3 deaths), Germany (6 cases), Croatia (6 cases) and Cyprus (5 cases). EU-neighbouring countries have reported 93 human cases of WNV infection, including 2 deaths, from Serbia (91 cases, 2 deaths) and North Macedonia (2 cases). To compare, 1,340 autochthonous human cases of WNV, and 104 associated deaths were reported during 2022. During the current 2023 WNV transmission season, autochthonous human cases of WNV infection were reported from multiple new regions in France, Greece, Italy, Romania, Spain, and one new region in Germany. Please see ECDC’s Communicable Disease Threats Report for further information.

On 17 November 2023, media reported 159 suspected and 11 confirmed cases of WNV in Tunisia (in Arabic). The Tunisian Ministry of Health is conducting enhanced surveillance, risk communication and implementing vector control measures in the affected governorates.

In 2023, as of 28 November, 2,284 WNV cases have been reported from 47 states in the USA. Colorado, California, and Nebraska have reported the most cases. This compares to 1,132 WNV cases, including 93 deaths reported in 2022.

Yellow fever

The Africa CDC have reported 2,832 yellow fever cases, of which 144 cases were confirmed between January and 24 November 2023. Cameroon reported 48 cases, including 6 deaths, Republic of the Congo reported 326 cases and 5 deaths, Gabon reported 113 cases, Guinea reported 178 cases and 4 deaths, Uganda reported 12 cases, and Nigeria reported 1,819 cases and 21 deaths.

Zika virus 

In 2023, as of 29 November 2023, the Region of the Americas has reported 31,781 cases of Zika virus infection, of which 3,290 have been confirmed. Countries reporting the most cases include Brazil (30,132 cases), Bolivia (863 cases) and Belize (281 cases). This compares to 40,528 Zika cases (including 3,547 confirmed cases) reported in the 2022.

Novel pathogens and diseases

Tribec virus

A recently published study aimed to characterise the virome of Ixodes ricinus ticks collected from France and Romania. Among the diverse viruses identified, a novel strain of Tribec virus was found in Romanian ticks, and 6 novel strains of Bronnoya-like virus were detected in Norway, Croatia, and Romania. This study highlights the importance of identifying novel pathogens to maintain surveillance of their emerging capabilities.

Ozark virus

Hispid cotton rats are a known reservoir of various orthohantaviruses in the USA. A recent study reported the detection of a novel orthohantavirus species, named Ozark orthohantavirus or Ozark virus (OZV), in this rodent species in the Ozark Plateau Region of Arkansas. The authors concluded that continued orthohantavirus surveillance and virus sequencing are needed to understand the potential public health threat of this virus.

Publications of interest

Andes virus

Andes orthohantavirus (ANDV), endemic to Chile and southern Argentina, can cause hantavirus cardiopulmonary syndrome (HCPS) in humans. A recent study reported the persistence of ANDV within the reproductive tract for at least 71 months, in a male individual who had recovered from HCPS 6 years earlier. Further research is needed to determine the potential for sexual transmission of the virus and whether persistence occurs in a larger population of long-term survivors of ANDV infection.

Chikungunya

On 09 November 2023, the US Food and Drug Administration approved Ixchiq for use in individuals 18 years of age and older who are considered to be at increased risk of exposure to chikungunya virus. Ixchiq, a single dose live attenuated intramuscular vaccine, is the first chikungunya vaccine to be approved.

Ebolavirus

A recent study aimed to assess the effect of monoclonal antibodies on anti-Ebolavirus antibody responses in survivors of the 2018 to 2020 Ebola virus disease (EVD) outbreak in the DRC. Authors suggest that monoclonal antibodies might negatively affect the production of anti-Ebolavirus antibodies in survivors of EVD, which could increase the risk of reinfection or reactivation.

Malaria

The use of genome sequencing as a diagnostic and surveillance tool in clinical settings is increasing. A recent study exhibited the benefits of the recently developed Malaria-Profiler tool, which study authors concluded to be capable of rapidly predicting Plasmodium species, geographical source and resistance to antimalarial drugs, directly from whole genome sequencing data. This tool has the potential to be integrated into point-of-care and surveillance settings, to assist with malaria control.

WHO’s annual world malaria report provides a comprehensive and up-to-date assessment of trends in malaria control and elimination across the globe. In 2022, malaria case numbers reached 249 million globally, which was well above the estimated number of cases before the COVID-19 pandemic, and an increase of 5 million cases when compared to 2021 data. The 2023 world malaria report describes climate change as one of many threats to the global response to malaria. Conflict and humanitarian crises, resource limitations and biological challenges (for example drug and insecticide resistance) also continue to hinder progress.

Marburg virus

Marburg virus (MARV) and Ravn virus (RAVV) are the causative agents of Marburg virus disease (MVD). A recent study developed an immunochromatography (IC) assay for the rapid diagnosis of MVD. The assay was able to detect MARV and RAVV in infected tissue cultures, and MARV and RAVV antigens in serum samples from experimentally infected nonhuman primates. These results suggest the potential for the use this IC assay for rapid point-of-care diagnosis of MVD.

Nipah virus

There are currently no approved vaccines to protect against Nipah virus (NiV) infection. A recent study developed a recombinant chimpanzee adenovirus-based vaccine (AdC68-G) and a DNA vaccine (DNA-G). The vaccines induced immunity (maintained up to 68 weeks depending on the number of doses, priming-boost regime and method of vaccine administration) against Nipah virus infection in an animal model. These findings support further investigations into the use of the AdC68-G and DNA-G vaccines against NiV infection.

A recently published study used an attenuated rabies virus strain, SRV9, to construct 2 recombinant viruses, rSRV9-NiV-F and rSRV9-NiV-G, which display the NiV envelope glycoproteins F and G, respectively. The authors found that inactivated rSRV9-NiV-F and rSRV9-NiV-G alone or in combination, mixed with adjuvants were able to induce antigen-specific cellular and Th1-biased humoral immune responses in mice. These findings also support further investigations into the use of rSRV9-NiV-F or rSRV9-NiV-G as vaccine candidates against NiV infection.

Tick-borne viruses

Ticks can transmit various emerging zoonotic pathogens which can pose a threat to human health. A recent study aimed to assess the risk of tick-borne diseases in Switzerland. The study reports the first detection of Alongshan virus (ALSV) in Swiss ticks, via metagenomic analysis. The authors concluded that the high abundance of ALSV identified in ticks in this study, suggests a reservoir in animal species that remains to be identified. Further studies to assess the potential risk of ALSV as an emerging zoonotic pathogen are needed.

Ixodid ticks can act as a primary reservoir for tick-borne encephalitis virus (TBEV). In a recent study, samples of ectoparasites (larvae, nymphs, and females of ixodid ticks) were removed from reptiles, collected from the Caucasus Region. Authors identified TBEV in one specimen of Ixodes ricinus tick retrieved from a Caspian green lizard, a common species widely distributed in the Caucasus region. Apart from confirming TBEV in the Caucasus Region for the first time, the study also identified the potential role of reptiles in the circulation of TBEV. The authors conclude that further studies investigating the role of reptiles in the spread of pathogens are necessary.

A study analysing tick samples collected in Poland, Bulgaria, Ukraine, Georgia, and the Black Sea region, detected human pathogens across 7.3% of sample pools. Tick-borne viral pathogens included Tacheng tick virus 2 (5.9%), Jingmen tick virus (0.9%) and Tacheng tick virus 1 (TTV1, 0.4%); this was the first reported detection of TTV1 on the European continent. The authors concluded that these viruses should be included in the diagnostic assessment of symptomatic cases associated with tick bites and vector surveillance efforts.

Further reading

Antimicrobial Resistance

Antimicrobial resistance research – an IJID collection of selected articles 2020-2023

Surveillance of antimicrobial resistance in Europe, 2022 data

Malaria

Changes in contributions of different Anopheles vector species to malaria transmission in east and southern Africa from 2000 to 2022

Marburg virus

A mathematical model of Marburg virus disease outbreaks and the potential role of vaccination in control

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

Authors of this report

UKHSA’s Emerging Infections and Zoonoses team [email protected]