UKHSA: Updated Risk Assessment On Mpox Clade Ib

 

Credit UK HSA

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Over the past 10 days we've seen signs of community transmission of the emerging Mpox Clade Ib virus reported both in the United States (see Los Angeles County Reported 3 (locally acquired) Clade I Mpox Cases) and in Europe (see ECDC Statement & Threat Assessment Brief Following Recent Reports of Local Transmission of Mpox Clade Ib in Europe). 

While local (usually household) transmission outside of Africa has been previouslyl reported by a few countries, it has been rare, and has nearly always been traced to known contact with a recent traveler from Africa.

In response to these recent reports of community transmission,  yesterday the UK's Health Security Agency (UKHSA) published an updated risk assessment, their first since December of 2024.  

While this 20-page document provides a number of plausible scenarios, it starts off with the following. 

Summary

Since the last technical assessment on 19 December 2024:

• the epidemiology of clade I mpox may have changed with person-to-person transmission now occurring outside the African Region including amongst specific gay, bisexual and other men-who-have-sex-with-men (GBMSM) networks in at least 2 other WHO regions (EURO and PAHO)

• the probability of importation into the UK has increased from medium to high

• the risk of onwards transmission in the UK is likely to be controlled to some degree by the existing GBMSM vaccination programme and remains low to medium at present; however there are significant uncertainties in this assessment relating to the circulating virus properties, the groups at risk and the level and duration of immunity from natural infection or vaccine. 

A year ago the UK released their Updated Mpox Technical Briefing #9 which presented 3 possible scenarios for the spread of Mpox in the UK ranging from the least to most impactful.

A) incursions and small clusters of cases,

B) a controllable epidemic, and

C) community transmission

At that time, the UKHSA stated that `. . . Currently indicators are most compatible with scenario A . . .'.  

But less than 4 months later (Dec 2024), this had shifted to " . . . The indicators are currently most compatible with scenario B – a virus with moderate transmissibility (similar to or slightly exceeding the transmissibility of the clade II outbreak).'

Today's update, while acknowledging the possibility of seeing a wider epidemic (Scenario C), keeps the previous assessment, stating:

Since the last technical briefing published on 19 December 2024, indicators continue to be assessed as being most compatible with Scenario B based on the transmissibility of the virus.

While our assessment is that globally we are in Scenario B (a controlled epidemic), in Africa initial transmission is among adults driven by close contact, including sexual contact, with a shift to younger age groups where initial clusters are not controlled. It is uncertain whether community transmission is self-sustaining without sexual transmission seeding outbreaks.  

You'll want to follow the link to read the full report, which discusses uncertainties regarding both transmission of the virus and the effectiveness and duration of protection from the current JYNNEOS vaccine.

(For more background see Preprint: The Two-dose MVA-BN Mpox Vaccine Induces a Nondurable and Low Avidity MPXV-specific Antibody Response).

The report concludes with the following:

4.2 Future assessment

It is highly likely that the number of imported cases outside of Africa will increase in the next 6 months (moderate confidence). There has been a deterioration in the epidemiology of the outbreak in Africa in the last 12 months. The number of countries with community transmission of clade I mpox has increased from 1 to 9 countries, some of which have greater connectivity to Europe (For example, Uganda and Kenya).

It is likely there will be an increase in secondary transmission and larger outbreaks are likely to occur in at risk populations outside of Africa in the next 6 months (low confidence). 

There are signals that there may be increasing transmission outside of Africa, including possible undetected transmission in countries. Additionally, there is evidence of community transmission of clade I mpox within the GBMSM community.  

Front. Immunol.: Distinct Characteristics of T cell Receptor Repertoire Associated with the SARS-CoV-2 Reinfection

 

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While most people now trivialize COVID infection as little more than a `bad cold' - and COVID vaccine uptake has dropped precipitously - at the same time we've seen consistent and compelling evidence that repeated SARS-CoV-2 infections can lead to `Long COVID' and other sequalae. 

Preprint: Incidence of Long COVID Following Reinfection with COVID-19

CSIRO Pub: Impacts of Long COVID on Disability, Function and Quality of Life for Adults Living in Australia

EHJ: Accelerated Vascular Ageing After COVID-19 Infection: The CARTESIAN Study

EID Journal: Estimates of Incidence and Predictors of Fatiguing Illness after SARS-CoV-2 Infection

These are not new discoveries, as early as January of 2023 the AMA released a statement (see What doctors wish patients knew about COVID-19 reinfection) calling reinfection `problematic' and equating it to `. . . playing Russian roulette" with the virus.

The CDC states:

Most people with Long COVID experience symptoms days after first learning they had COVID-19, but some people who later develop Long COVID do not know when they were infected. People can be reinfected with SARS-CoV-2 multiple times. 

Each time a person is infected with SARS-CoV-2, they have a risk of developing Long COVID.  Long COVID symptoms and conditions can emerge, persist, resolve, and reemerge over weeks and months. These symptoms and conditions can range from mild to severe, may require comprehensive care, and can even result in a disability.

Like it or not, there is evidence that COVID remains more than just a garden-variety respiratory virus. Elevated rates of hypertension, diabetes, and stroke have all been reported following COVID infection. 

Less clear are (often anecdotal) reports of increased susceptibility to viral or bacterial infections, particularly after repeated COVID infections.   

Today we've a report, published last week in Frontiers in Immunology, which finds (among a relatively small, single-center study) that people who contract COVID-19 more than once have reduced diversity in their T cell receptors, which are crucial for fighting infections. 

They compared blood samples from 48 individuals aged 20–40 across three cohorts (18 Primary Infection, 18 Reinfections, and 12 Healthy Controls), and found distinct differences in T Cell populations.

This study is causing quite a stir online, but the authors caution that these findings are correlative, and do not establish whether these observed immune changes are the primary drivers of post-infection sequalae. 

This is, as you might imagine, a highly detailed and technical report, and I'll leave it to others far more qualified than I to opine further.  I've reproduced the Abstract, and a few brief excerpts below.  

Follow the link to read it in its entirety.  I'll have a brief postscript after you return. 

Distinct characteristics of T cell receptor repertoire associated with the SARS-CoV-2 reinfection

Liling Zeng , Li Liu , Baolin Ren , Bing Feng , Xudong Lai, Xunxi Lai, Zhimin Chen , Yihui Huang, Wenxin Hong 

Abstract

The COVID-19 pandemic, caused by SARS-CoV-2, represents one of the most profound global public health challenges in modern history. While T cell immunity is crucial for viral clearance, the dynamics of the T cell receptor (TCR) repertoire during reinfection remain poorly understood. 

This study sought to characterize the TCR repertoire in peripheral blood T cells from healthy convalescent individuals (HC), patients with primary SARS-CoV-2 infection (PI), and reinfected individuals (RI), aiming to identify distinct TCR signatures linked to susceptibility or protection against reinfection.

We enrolled 48 age- and sex-matched participants (18 PI, 18 RI, 12 HC), collecting blood samples during acute infection (PI/RI) or convalescence (HC). Deep TCRα/β sequencing was performed using the SMARTer Human TCR Profiling Kit with unique molecular identifiers (UMIs), followed by analysis of TCR repertoire diversity, clonal expansion, V(D)J gene usage, and CDR3 characteristics. 

Compared to HC, both PI and RI groups exhibited significantly reduced TCR diversity (p< 0.001), though no significant differences were observed between PI and RI. COVID-19 patients displayed skewed TCR repertoires dominated by expanded clones (>1%), whereas HC primarily harbored small clones (≤ 0.1%). RI patients demonstrated intermediate clonality, suggesting partial memory recall. Group-specific V(D)J pairings were identified, including TRAV27/TRAJ42 in RI, TRAV24/TRAJ42 in PI, and TRAV35/TRAJ42 in HC, while TRBV6-4/TRBD2/TRBJ2–3 was conserved across all groups. Additionally, HC-enriched and RI-exclusive CDR3 clusters were detected.

Our findings indicate that SARS-CoV-2 reinfection is associated with impaired TCR diversity and distinct clonal expansion patterns, underscoring the role of T cell immunity in reinfection susceptibility. HC-enriched TCR clusters may represent protective memory responses, whereas RI-specific signatures suggest compromised immunity. These results offer valuable insights for vaccine design and risk stratification, though further functional validation of the identified TCRs is necessary.

        (SNIP)

Our study reveals distinct TCR repertoire signatures associated with SARS-CoV-2 reinfection, characterized by reduced clonal diversity, antigen-driven expansion, cohort-specific V(D)J recombination patterns, and exclusive CDR3 AA sequence clusters.

The HC-enriched TCR clusters likely represent protective memory T-cell populations, whereas the PI/RI groups exhibited repertoire dynamics consistent with antigen-specific selection pressure.

Notably, the significant divergence between RI and HC repertoires suggests compromised T-cell immunity in reinfected individuals, potentially explaining their susceptibility to recurrent infection. We suppose that these TCR sequences represent clonotype subsets that confer SARS-CoV-2 immunity, and that their depletion or dysregulation may contribute to the pathogenesis of reinfection. This interpretation is consistent with other viral models, such as influenza, in which T-cell-mediated immunity has been shown to play a critical role in protection against reinfection (39, 40). These findings advance our mechanistic understanding of recall T-cell responses in reinfection and inform rational vaccine design and immunotherapeutic strategies.

While this study enhances our understanding of T-cell responses in reinfection, several limitations should be noted. First, as a curated database, VDJdb is subject to coverage bias and may overrepresent certain epitopes while underrepresenting others. Second, TCR specificity inferences rely on sequence similarity and previously reported associations in VDJdb and have not been experimentally validated in our cohort. Furthermore, functional assays, such as TCR specificity testing and epitope mapping, are needed to confirm the protective role of the identified T-cell clusters and to elucidate the mechanistic basis of their effects.

        (Continue . . . )

While I risk getting another warning letter from the ASPCA for continuing to beat a dead horse, this is probably the 100th study we've looked at that has found credible evidence of long-term damage from COVID infection. 

A few recent examples include:

• Last Month, in European Society of Cardiology: Major Consensus Statement Released on Long-Term Cardiovascular Impact of COVID Infection, researchers found `. . . Covid infection and long Covid have serious effects on the heart and blood vessels, and the pandemic has had a widespread and lasting impact on cardiovascular health.'

• Last June, in BMC Neurology: Long-term Neurological and Cognitive Impact of COVID-19: A Systematic Review and Meta-analysis in over 4 Million Patients, we saw that neurological symptoms are both common and persistent in COVID-19 survivors.

• Last May, in Brain, Behavior & Immunity: COVID-19 may Enduringly Impact Cognitive Performance and Brain Haemodynamics in Undergraduate Students, we looked at a study of 94 undergraduates, which found that 37% of previously infected students showed cognitive impairment up to 17 months post-infection.

Which is why I got both my updated COVID and seasonal flu shot from my local pharmacist a couple of weeks ago, and I continue to wear a (KN95) face mask in crowded indoor environments. 

While these precautions may not be 100% protective - they can go a long way toward reducing my risks of infection. 

And given my age - and my limited number of functioning neurons - it seems like cheap insurance to me. 

A Robust Start To Avian Flu Season In Europe & North America

 

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Although we've already seen an early start to avian flu here in the United States (see Avian Flu's Unusually Active September in the United States), reports from Canada and Europe over the past couple of weeks suggest they are seeing a similar pattern. 

As the chart above illustrates, since the emergence of the clade 2.3.4.4b H5N1 virus in 2020-2021, the amount of bird flu activity has varied considerably from year-to-year, with 2023-2024 showing the lowest peaks. 

Hopes that trend might continue were dashed, however, as the last 12 months (2024-2025) provided a new surge, with ample detections continuing over the summer. As in North America, Europe is now reporting an early and vigorous start to this fall's avian flu season. 

Exactly what might be driving this fall' surge in detections isn't clear, as genotype information has been slow to emerge (see Nature: Lengthy Delays in H5N1 Genome Submissions to GISAID).

While we've seen no updates from Canada in nearly a week on the situation in Alberta (see Canada: Alberta Petting Zoo Closed For HPAI H5 - Recent Visitors Asked to Monitor For Symptoms), the CFIA has added 8 new outbreaks (across 3 Provinces) in the past 5 days, making 22 since the 1st of the month. 

Despite the government shutdown, the USDA has been updating their avian flu in poultry page (although, reports may be slower to be added).  As the following chart suggests, avian flu season is well underway here as well. 

Across the pond, the UK has announced 8 outbreaks in poultry since Oct 1st, with 3 in the past 72 hours.

In Germany, hundreds of cranes have reportedly died from HPAI, a number of  farms have been affected, and yesterday the FLI issued the following short statement:

Avian influenza: FLI updates answers to frequently asked questions

10/24/2025

The rapidly developing avian influenza outbreak in Germany is generating numerous inquiries at the Friedrich Loeffler Institute ( FLI ). The updated answers to frequently asked questions ( FAQs ) explain, among other things, why cranes are a severely affected wild bird species this fall.

The FLI appeals to the public in affected areas to stay away from wild birds and not to disturb them. Please report dead wild birds to the relevant veterinary authorities.

FAQ Highly Pathogenic Avian Influenza (Fowl Flu), as of October 24, 2025 ( PDF )

Germany's most recent update (Risk assessment for Highly Pathogenic Avian Influenza H5 ( HPAI H5) Clade 2.3.4.4B, as of 20 October 2025 ( PDF )) cites:

Situation in Germany: Between September 1 and October 20, 2025, 15 HPAIV H5N1 outbreaks were detected in poultry in seven federal states in Germany (Fig. 1). Chickens, geese, ducks, and turkeys were affected, with production in fattening, breeding, and laying hen farms. The largest affected farm was a broiler parent flock in Mecklenburg-Western Pomerania with over 35,000 birds.

This past week France raised their avian flu risk to the their highest level, and there are a growing number of reports from other European nations, including Belgium, Italy, and Spain. 

While I've no desire to try to track every outbreak across Europe or North America, it is important to note trends.  And so far, avian flu activity this fall has been robust. 

Although the risks to the general public are considered low right now, those who raise backyard poultry are presumed to be at greater risk of infection. 

Credit CDC

A couple of weeks ago, in UF/IFAS Extension: What Backyard Flock Owners Need to Know about Bird Flu (Influenza H5N1), we looked at some expert advice on protecting your flock - and your health - from avian flu. 

While it is too soon to know how this year's avian flu season will stack up against past years, it has started 30 to 60 days earlier than usual - and in recent years HPAI has surprised us repeatedly as it has expanded both its host and geographic range. 

Stay tuned, and fasten your seat belts. It could be a bumpy ride. 

WOAH Statement (Oct 22nd): High Pathogenicity Avian Influenza (HPAI) in Cattle

Credit WOAH

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Not quite 2 weeks ago we looked at an 11-page OFFLU technical document (see OFFLU Guidelines for High Pathogenicity Avian Influenza Virus Risk Mitigation in Cattle) which outlined new - and far more robust - recommendations on HPAI risk mitigation in cattle.

That report came with a disclaimer: This document provides the point of view of independent OFFLU experts and does not necessarily reflect the position of the parent organisations FAO and WOAH.

While acknowledging that policies must be tailored to work with varying local resources and production systems, that 11-page guidance document made sweeping recommendations on a variety of fronts, including:

• Implementing risk-based bulk milk surveillance

• Enforcing pasteurization and safe disposal of waste milk

• Applying flexible movement controls with testing and quarantines

• Improved biosecurity & milking practices

• Protecting workers with PPE  

This week WOAH (The World Organization for Animal Health) issued their own Policy statement; one which closely aligns with the technical recommendations from the recent OFFLU document.

Although WOAH began asking member states to notify them of any outbreaks in cattle last spring (based on a February SCAD report), in this week's statement they make it mandatory, stating:

In light of the impact on animal and public health, the Scientific Commission for Animal Diseases considered at its February 2025 meeting that ‘infection of bovines (Bos taurus) with influenza A viruses high pathogenicity’ meets the Terrestrial Code glossary definition for ‘emerging disease’. Accordingly, Members are required to notify the occurrence of HPAI in cattle to the World Animal Health Information System (WAHIS) in accordance with the WOAH Terrestrial Code Article 1.1.4.

WOAH also reminds its 183 Members that, based on the information currently available, restrictions to the international trade of healthy cattle and their products are only recommended if justified by an import risk analysis conducted according to the WOAH Terrestrial Animal Health Code Chapter 2.1.   

They then proceed to endorse the recommendations from the OFFLU report:

Finally, WOAH invites Members to consult OFFLU Guidelines for High Pathogenicity Avian Influenza Virus Risk Mitigation in Cattle. These guidelines  provide practical, evidence-based measures to support Members in their efforts to  mitigate the risk of HPAI virus spread in cattle. It outlines key transmission pathways and proposes proportionate intervention strategies based on the latest scientific evidence.

While I've provided an excerpt below, the full policy statement can be read at: https://www.woah.org/en/high-pathogenicity-avian-influenza-hpai-in-cattle/

I'll have a brief postscript after the break.

WOAH calls on its Members to:

• Increase avian influenza surveillance in domestic and wild birds.
• Enhance surveillance for early detection in cattle population in countries where HPAI is known to be circulating.
• Include HPAI as a differential diagnosis in non-avian species, including cattle and other livestock populations, with high risk of exposure to HPAI viruses, in particular: 

• Animals showing clinical signs compatible with avian influenza;
• Sick or dead domestic animals near HPAI affected premises; and
• Suspected cases, including apparently healthy animals, that have been exposed to or epidemiologically linked to suspected or confirmed HPAI in birds or cattle (i.e. situated in HPAI high-risk areas or in areas where avian influenza has been confirmed). 

• Notify cases of HPAI in all animal species, including cattle or other unusual hosts, to WOAH through its World Animal Health Information System (WAHIS). Genetic sequences of avian influenza viruses should be shared in publicly available databases.
• Consider OFFLU ‘Guidelines for High Pathogenicity Avian Influenza Virus Risk Mitigation in Cattle’ .
• Implement preventive and early response measures to break the HPAI transmission cycle among animals. These include applying movement restrictions of infected livestock holdings until infection has stopped and strict biosecurity measures in all holdings, in particular in milking parlours.
• Employ good production and hygiene practices when handling animal products. Raw milk or raw milk products from HPAI infected or exposed cows should not be used for animal feed or for human consumption.
• Protect humans in close contact with or handling sick cattle or other sick livestock and their products. Exposed humans should always take precautionary measures to avoid getting infected and minimise the risk to mechanically carrying the virus to livestock or companion animals. This should include wearing personal protective equipment, avoiding visiting other livestock premises after the exposure and implementing standard food safety measures when handling animal products from exposed livestock.
• Avoid implementing unjustified trade restrictions. Import risk management measures should be scientifically justified and in line with the WOAH International Standards.

• Technical guidelines for the adaptation of diagnostic tests for Influenza A in animals including cattle and other species as well as different types of samples such as milk and nasal swabs are available in the OFFLU website and will be regularly updated.

• WOAH is fully committed to supporting its Members to mitigate the risks associated with avian influenza. We will continue to engage with our networks of experts, OFFLU, as well as public and private partners, notably through the One Health Quadripartite and the Global Framework for Transboundary Animal Diseases (GF-TADs) to provide technical updates as more information becomes available.
  

            (Continue . . . )

While both of these documents are encouraging signs that the world is starting to take HPAI in cattle as a serious threat, they come more than 18 months after the first HPAI outbreak was reported in Texas dairy cows.   

For the better part of a year, it was assumed that only the North American B3.13 genotype was capable of spilling over into cattle, making this an American - not a world - problem. 

Slowly those hopes have eroded:

• First, following a statement from Germany's FLI on the Experimental Infection Of Dairy Cows With A European H5N1 Virus in June of 2024

• Followed by reports of H5N1 antibodies found in Pakistani goats and sheep.

• Since February we've seen another strain (genotype D1.1) spillover into dairy cattle in two states (Nevada & Arizona)

• And in recent months we've seen additional evidence of infection with other strains in both a UK sheep and in sheep in Norway.

`Mandatory' or not, it remains to be seen how willing member nations, animal health agencies, and farmers will be to embrace these policy recommendations, and to report cases. 

As our global track record to date (see From Here To Impunity), has not been particularly encouraging.  

ECDC Statement & Threat Assessment Brief Following Recent Reports of Local Transmission of Mpox Clade Ib in Europe

 

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A week ago Los Angeles County Reported 3 (locally acquired) Clade I Mpox Cases, raising concerns of community spread in the United States. Similarly, last Friday the ECDC reported on a single, locally acquired case of Mpox Clade I in Madrid, Spain.

While local transmission outside of Africa has been reported previously, it has been rare, and most have been traced to  known contact with a recent traveler from Africa. 

Mpox Clade Ib is a different, and potentially more severe, strain of Mpox which emerged in East Central Africa in late 2023 and should not be confused with the milder Mpox Clade II which began to spread internationally in 2022.

Today the ECDC has announced 4 more recent autochthonous cases of Mpox Clade Ib (Italy =2, Portugal =1, and the Netherlands =1), and has published a Threat Assessment for the EU/EEA. 

First the news summary, followed by the link and some excerpts from the Threat Assessment:

Local transmission of clade 1b mpox cases detected in EU/EEA, ECDC urges renewed vigilance
News
24 Oct 2025

Following the first detections of locally acquired mpox clade Ib cases within the European Union and European Economic Area (EU/EEA), the European Centre for Disease Prevention and Control (ECDC) is calling for heightened awareness and targeted prevention measures.

Locally acquired mpox cases have now been confirmed in four countries. Spain reported its first such case on 10 October 2025, and the Netherlands on 17 October 2025. These have been followed by additional cases reported in Italy (2) and Portugal (1). This development is distinct from the previously reported travel-associated clade Ib cases between August 2024 and October 2025, mostly among returning travellers from mpox-endemic areas outside of the EU. These new cases have been reported among men, some of whom identify themselves as men who have sex with men, with no recent travel history to mpox-endemic areas. This indicates that transmission may be ongoing in sexual networks among men who have sex with men in European countries.

Transmission among gay, bisexual, and other men who have sex with men and their social networks has also been recently reported in California, USA, after the detection of three unlinked clade Ib cases.

While the immediate risk to the general population of acquiring the disease is low, the overall risk of infection is moderate for men who have sex with men. The risk of severe disease may be higher for those living with untreated HIV. Some uncertainties remain regarding the transmissibility and clinical severity of clade Ib compared to the clade IIb virus that has circulated since 2022. Among 29 clade Ib cases reported to ECDC before the current cases, seven were hospitalised for treatment, although with such a small number of cases, any estimation of severity in comparison to clade IIb is uncertain.

To prevent further spread, there is a need for a multi-pronged public health response. This includes ensuring testing is easily accessible, especially in sexual health clinics, and that mpox vaccination is actively offered to gay, bisexual and other men who have sex with men. Prompt identification and isolation of new cases and contact tracing to identify contacts and offer them vaccination are essential to control transmission. Public health authorities should work closely with civil society and community-based organisations that serve men who have sex with men to promote awareness and vaccination uptake, using respectful, non-stigmatising language and targeted communication channels.

Mpox is usually acquired through direct contact – such as sex or skin-to-skin contact – with people who have the disease. Vaccination offers the best protection, and individuals at higher risk of exposure, such as gay, bisexual, or other men or transgender people who have sex with men, should seek vaccination proactively. They can check with national health authorities or sexual health clinics for information on who is eligible for vaccination and where to access it.

Doctors should consider offering post-exposure vaccination to close contacts of cases, including sexual partners and individuals with other prolonged physical or high-risk contact, because the vaccine has been shown to confer protection even after exposure.

Sexually active individuals should be aware of the symptoms of mpox and how to protect themselves and others. Symptoms include a typical rash (pimples or blisters) on any part of the body, which can be limited to a few lesions or be widespread, sometimes accompanied by fever, cough, sore throat or other flu-like symptoms or swollen lymph nodes. If an unusual rash develops, they should seek medical help by contacting a healthcare professional for testing and advice. It is also important to avoid close physical or sexual contact with others until they are symptom-free.

Threat Assessment Brief: Detection of autochthonous transmission of monkeypox virus clade Ib in the EU/EEA

Assessment

24 Oct 2025

This Threat Assessment Brief aims to assess the risk of autochthonous transmission of monkeypox virus (MPXV) clade Ib in EU/EEA countries in the context of male-to-male sexual transmission. It is intended for public health authorities in EU/EEA countries and is based on currently available evidence. It therefore carries considerable uncertainty. Recommendations how public health authorities can respond at the country level together with an overview of knowledge gaps in the context of MPXV clade Ib are also included.

Epidemiological situation

• On 10 October 2025, Spain reported its first locally acquired clade Ib mpox case. On 17 October, four additional clade Ib mpox cases were reported to ECDC among males without travel history by Italy (two), Portugal (one) and the Netherlands (one). All five cases had mild symptoms. Some of the individuals reported having sexual contact with another male.
• These recent cases, where there is no travel history, represent a different pattern of transmission and indicate that transmission may be occurring in sexual networks among men who have sex with men in several EU/EEA countries. The 30 clade I mpox cases reported in the EU/EEA previously were all imported or had clear links to imported cases.

Risk assessment

• Based on current evidence, the overall risk of MPXV clade Ib infection is assessed as moderate for men who have sex with men and low for the general population.
• It is likely that further cases are present among men who have sex with men in the EU/EEA but have not yet been detected. ECDC will continue to closely monitor and review this risk assessment should the situation evolve into a larger outbreak.

Recommendations

• EU/EEA countries should ensure laboratory testing is easily accessible, particularly in locations that serve men who have sex with men, and that clinicians and laboratories can report cases to public health authorities rapidly.
• Identifying clades should be done where individuals have been diagnosed with mpox, and clade I viruses should be sequenced as soon as possible.
• Vaccination should be made available to all individuals at substantially higher risk of exposure to MPXV, in addition to other preventive measures. Public health professionals should advise individuals om groups at higher risk of infection to seek vaccination proactively.
• Contact tracing should be carried out after a case is identified, to enable control of onward transmission as well as to contribute data that will allow for an assessment of transmission dynamics.
• Public health authorities should continue risk communication activities around mpox and partner with civil society organisations that serve men who have sex with men to build trust in health services, provide advice on seeking medical assistance and improve vaccination coverage.

Download


Detection of autochthonous transmission of monkeypox virus clade Ib in the EU/EEA - EN - [PDF-672.37 KB]

While largely ignored by the Western world, Mpox has been spreading unchecked, and evolving, in West and Central Africa for decades. 

A 2016 study (see EID Journal:Extended H-2-H Transmission during a Monkeypox Outbreak) looked at a large 2013 outbreak of Monkeypox in the DRC and suggested that the virus's epidemiological characteristics may be changing (possibly due to the waning smallpox vaccine derived immunity in the community).

The DRC reported a 600% increase in cases over both 2011, and 2012.  The authors also cite a higher attack rate, longer chains of infection, and more pronounced community spread than have earlier reports.

While the 2022 world tour by the milder Mpox clade IIb virus was eventually largely suppressed, it continues today, and reining in clade Ib may prove even more challenging.   

One of the realities of life in this third decade of the 21st century is that the world is a lot smaller than used to be. Vast oceans and extended travel times no longer offer the protection they once did, and there is no technological shield that we can erect that would keep an emerging virus out.

Making it is penny wise and pound foolish when we choose to ignore these types of outbreaks, no matter where they occur. 

Australia DAFF & DCCEEW: Suspected H5 bird flu in Elephant Seals at Australian Sub-Antarctic Island

Heard & McDonald Islands - Credit Wikipedia

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Today only Australia, NZ, and the islands of Oceania remain free of the HPAI H5 virus, and while they are protected by vast oceans, most experts expect the virus will arrive there eventually.

Australia does have indigenous LPAI viruses, which occasionally mutate into HPAI varieties. Last year we followed outbreaks of 3 different HPAI H7 viruses across 3 territories (see Australia: 11th Avian H7 Outbreak, Now Reported in ACT).

Oceania's protection has often been attributed to the Wallace and Weber lines; imaginary dividing lines used to mark the difference between animal species found in Australia and Papua New Guinea and the rest of Southeast Asia (see 2008 study Will Wallace’s Line Save Australia from Avian Influenza?).

On the western side you'll find large mammals, like Elephants, monkeys, leopards, tigers, and water buffalo. While on the eastern side, you'll mostly find marsupials (kangaroos, Koalas, wombats, etc.). 

These stark faunal differences also extend to birds, reptiles, and even insects.

But the introduction of H5N1 to Antarctica two years ago may now provide the virus with a potential southern route that could circumvent the Wallace and Weber lines. In late 2023 OFFLU warned:

Given movement data demonstrating connectivity between the polar front to both the Antarctic and Subantarctic islands of Oceania, and Oceania itself, it is plausible that if HPAI H5 were present in the Antarctic region directly south of Oceania, it could be introduced to Oceania.

Since 2022 we've also seen an Unprecedented `Order Shift' In Wild Bird H5N1 Positives, with many seabirds; including gannets, gulls, guillemots and great skua now hosting the virus. 

This increased avian host range likely helped to facilitate the arrival of HPAI to Hawaii last year, and could potentially do the same for Oceania. 

A little over a year ago we looked at an informative webinar, held by Australia's Biodiversity Council, on how they are preparing for HPAI H5's almost inevitable arrival. The 1-hour video is available on YouTube, and you'll find a link to a detailed summary below. 

Note: Some of the video clips of affected birds may be hard for some people to watch.

While it is still far-removed from the Australian mainland, today the Australian government released a joint statement on the discovery of unusual mortality - consistent with HPAI H5 - among elephant seals on the remote island of Heard. 

While HPAI H5 has not yet been confirmed (tests are pending), officials are obviously concerned enough to make this public announcement. 

The full press release follows, after which I'll have a brief postscript.

Suspected H5 bird flu in elephant seals at Australian sub-Antarctic Island

Media release
Environment
Environment protection

24 October 2025

Joint DAFF & DCCEEW media statement

Australian scientists have observed signs consistent with H5 avian influenza (bird flu) in wildlife during a management voyage to sub-Antarctic Heard Island.

At this stage it is not a confirmed detection. It reinforces the need for Australia to remain focused on preparing for an outbreak.

Heard Island is part of the Heard Island and McDonald Islands external Australian territory. It’s over 4000 km south west of Perth and 1700 km north of Antarctica in the Southern Ocean.

Australia remains the only continent free from the highly contagious strain of H5 bird flu. A confirmed detection on Heard Island would not substantially increase the risk to Australia.

Scientists observed unusual levels of mortality in elephant seals on Heard Island in recent days.

Observations were made by Australian Antarctic Program scientists on an environmental management visit to the island on board the RSV Nuyina. There were no observations of unusual levels of mortality in other species present on the island, including penguins and other seabirds.

Seeing signs consistent with H5 bird flu in wildlife on Heard Island is not unexpected. This virus has previously been found on the French Kerguelen and Crozet sub-Antarctic islands, which are less than 450 km from Heard and McDonald Islands.

Samples have been safely collected and securely packaged in accordance with International Air Transport Association (IATA) Dangerous Goods Regulations.

The samples will be submitted to the CSIRO Australian Centre for Disease Preparedness for confirmatory testing when RSV Nuyina returns to Australia in mid November.

It will take some weeks to get the results from these tests.

The Australian Government is investing more than $100 million into strengthening bird flu preparedness and enhancing our response capacity. Further information is available at birdflu.gov.au

While the introduction of HPAI H5 has been impactful for every new country or territory it has conquered, when H5N1 arrived in North American birds we saw an immediate explosion in reassortments with local (North American) LPAI viruses, and the generation of scores of new genotypes.

As a result, the United States has seen new variants emerge capable of infecting cattle and other livestock, a marked increase in its ability to infect smaller mammals, including cats, mice, and the spillover into > 70 humans. 

In addition to posing a devastating threat to Australia's ecology, Oceania's isolated, and HPAI-naive collection of LPAI viruses could conceivably provide the same sort of `accelerant' to H5N1's evolution. 

While it is always possible that Oceania's LPAI viruses will prove less compatible with HPAI H5, this is an uncontrolled field experiment we really don't want to see take place. 

Stay tuned.