Containing the Next Outbreak Part 1: FLI on Bird Flu and Pandemic Preparedness

As the world witnesses a resurgence of bird flu (avian influenza), the current situation reminds us how closely human, animal, and environmental health are intertwined. The virus is spreading across continents and species, and while human infections have been detected, scientists have not yet found evidence of person-to-person transmission, though the risk continues to evolve. Recent analyses show that the H5N1 strain is becoming more adept at spreading between cows, with mutations linked to improved replication in cells lining the airways of both cattle and humans. As evolutionary virologist Daniel Goldhill notes, these changes mark “a first stepping stone for the virus” and raise the risk of a jump to humans.

Against this backdrop, and following the recent Bundestag Health Committee hearing on the International Health Regulations (IHR), we spoke with Prof. Timm Harder, Head of WOAH, FAO and National Reference Laboratory for Avian Influenza (AI) / Poultry Plague at FLI, and Prof. Martin Beer, Head of the Institute for Virus Diagnostics and FLI Vice President about monitoring and surveillance, the growing threat at the animal–human interface, and how the revised IHR can help prevent the next pandemic before it starts.

How does FLI assess the current situation of highly pathogenic avian influenza (HPAI) in Germany and what are the main drivers behind the recent resurgence among wild and domestic birds?

The situation regarding HPAIV H5N1 remains tense, even though the peak in cases among wild birds and the mass deaths of cranes appear to have passed for the time being. More than 80% of the wild bird cases were caused by cranes, whose population was severely affected. It is estimated that more than 20,000 cranes nationwide have fallen victim to H5N1 infection. In terms of poultry cases, the focus was primarily on regions with a high density of poultry populations (BB, NI, NW). The majority of the more than 150 outbreaks to date (as of 30 November 2025) can be attributed to primary introductions of the virus; so far, there is little reliable evidence of secondary infections through transmission between poultry farms.

The detection of H5N1 in mammals such as seals, cats, and even cattle has raised concerns about adaptation to new hosts. How closely is FLI monitoring these developments, and what indicators would signal an increased risk of transmission to humans?

There is no state-organised monitoring programme for mammals. However, some federal states carry out extended investigations, particularly in the case of dead facultative scavengers (e.g. foxes, raccoons, mustelids). So far, three foxes and one cat have tested positive for HPAIV H5N1 since October. These infections are dead-end infections and are not transmitted to other mammals.

Increased exposure risks for humans currently arise mainly from the recovery of dead wild birds and the clearing of infected poultry farms. Appropriate protective clothing is therefore essential for people who collect wild bird carcasses or clear flocks.  There are no signs of any change in the risk to the general population, which is currently assessed as ‘low’ (ECDC/WHO assessment). Furthermore, there has been no human-to-human transmission to date.

Indicators of an increased risk would include, for example, the emergence of H5 variants that have mixed with human influenza viruses, adaptation and transmission within mammalian populations (especially pigs), or frequent human infections with additional adaptive mutations or new reassortants. Clusters of infection with human-to-human transmission would be a particularly serious warning sign. Therefore, all these scenarios must be taken into account for comprehensive preparedness and surveillance.

In light of recurring outbreaks, what immediate biosecurity measures should poultry farmers and local authorities strengthen to prevent spillover between species and ultimately, to humans?

Experience has shown that secure facilities can offer a certain degree of protection against infection, but there is no such thing as 100% security. Risk reduction is primarily achieved by creating effective barriers between poultry and wild birds for the protection of both. In the medium term, infrastructural adjustments must also be considered, especially in areas with a high density of poultry populations. Early detection also plays a particularly important role in containing outbreaks as early as possible.

While the International Health Regulations mainly govern public health emergencies, animal health institutions like FLI play a key role in early warning. How does FLI engage in Germany’s implementation of IHR-related surveillance and reporting systems? Are there existing communication channels with RKI and WHO networks under the One Health framework?

Through its reference laboratory and surveillance functions, the FLI is closely integrated into the IHR-related monitoring and reporting structures, ensuring that animal health information is incorporated into human medical assessments at an early stage. There is an established and long-standing exchange of information with the RKI at technical and management level, in which findings – for example on outbreaks in poultry, wild birds and mammals – are continuously shared and incorporated into the Public Health Intelligence Weekly Report in collaboration with the Federal Foreign Office. Internationally, the FLI is involved in the professional exchange on zoonoses via One Health formats such as GOARN and the WOAH/FAO network OFFLU, thus contributing to global early detection and risk assessment.

Given that avian influenza is a transboundary disease, how does FLI collaborate with European or international partners (e.g., WOAH, FAO, ECDC, WHO) to ensure rapid information exchange and coordinated response and how could such cooperation be strengthened under the updated IHR provisions?

The FLI maintains one of nine international FAO reference laboratories for influenza virus infections in animals worldwide. The head of the National Reference Laboratory is accredited as an expert on avian influenza by the WOAH and is a member of the steering committee of the OFFLU organisation, which brings together the forces of the FAO, WOAH and WHO in relation to influenza. There is currently a lack of funding for information and research projects in transcontinental exchange. OFFLU offers excellent global networks of experts for initiating and implementing such projects. The FLI also coordinates the EU-funded H5N1 consortium ‘Kappa-Flu’ and is part of the new BMFTR-funded consortium ‘Flu-Prep’ and the EU consortium ‘DURABLE’, which is linked to HERA.

In order to further promote and optimise networking within Europe, a network modelled on the US network ‘Centers of Excellence for Influenza Research and Response (CEIRR)’ would be highly desirable (see also Europe needs a sustainably funded influenza research and response network, Krammer, Florian et al., The Lancet Infectious Diseases, Volume 25, Issue 4, 369 – 372).

👉 More Information: Guidance from the RKI and FLI on intersectoral cooperation in cases of suspected avian influenza in animals for a coordinated One Health response (in German)

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