#19,134
We've a detailed report, published yesterday in Eurosurveillance, on a recent (Feb 2026) outbreak of HPAI H5N1 in poultry on a small holding in Germany, where domestic cats (n=9), and a number of people (n=17) were occupationally exposed.
Despite the high number of HPAI H5 outbreaks reported in Germany over the winter of 2025-2026 (see BHVSI-SA graphic below), biosecurity was practically nonexistent on this farm - and based on the lack of PPE use - the index of suspicion for HPAI appears to have been low for several days into the outbreak.
While no human infections were detected, testing was less than exhaustive (only symptomatic individuals were tested by RT-PCR & just 11 out of 17 of exposed submitted to serology); despite previous studies (see MMWR: Serologic Evidence of Recent Infection with HPAI A(H5) Virus Among Dairy Workers), suggesting that asymptomatic HPAI H5 cases may be relatively common.
The authors address some of these shortcomings in their report, stating:
Our analysis has limitations:
Firstly, systematic virological testing of all exposed individuals was not performed, as testing was limited to symptomatic persons, which represents a standard and pragmatic approach in this context. However, asymptomatic or subclinical infections may not have been detected.
(SNIP)
Fourthly, serological assessments of infection have several limitations. Antibody responses may be low or undetectable in asymptomatic or mildly infected individuals, and the timing of sample collection may not capture seroconversion.
Another concerning aspect to this report is the lack of seasonal flu vaccination among many of the responders (particularly among the Veterinary Authority Staff), and their parsimonious use of PPE (see chart below) during their initial site visits.
I've provided the link, abstract, and some excerpts from the report below, but you'll want to read it in its entirety. I'll have a postscript when you return.
Open Access
Highly pathogenic avian influenza A(H5N1) in poultry and domestic cats and occupational exposure among veterinary and other first responders, Germany, February 2026
Aparna Dressler1,2 , Christiane Wagner-Wiening1 , Bettina Tegtmeyer3 , Susanne Haag-Milz3 , Bettina Demattio4 , Ralf Dürrwald5 , Timm Harder6 , Andreas Salditt7 , Judith Köster7
Highly pathogenic avian influenza (HPAI) viruses continue to circulate in Europe, causing outbreaks in poultry and wild birds and occasionally infecting mammals [1-4]. Although human infections remain rare, zoonotic transmission is a recognised occupational risk for persons involved in animal husbandry, outbreak control, and veterinary response activities, and sporadic human infections with HPAI A(H5N1) have been reported globally [5]. An HPAI outbreak in poultry and cats in a small, remote poultry holding in Sigmaringen in February 2026 triggered a One Health investigation with 17 exposed persons.
Here we describe the outbreak, assess potential zoonotic transmission and evaluate the public health response within a One Health framework.
Outbreak detection and initial investigation
On 19 February 2026, the local public health authority in Sigmaringen, Baden-Wuerttemberg, Germany, was notified of a suspected avian influenza outbreak in a small poultry holding following veterinary inspections triggered by animal welfare concerns. The holding, which had no biosecurity measures, comprised ca 21 chickens and nine free-roaming cats and was located in a remote rural area. The birds were in a poultry house but had access to the outside and contact with wild birds.
Between 16 and 18 February, veterinary inspectors found four dead chickens and one dead cat on the premises. A further cat showing severe neurological symptoms was euthanised (Tables 1 and 2). Laboratory testing using real-time quantitative PCR (RT-qPCR) confirmed HPAI A(H5N1) infection in all six animals, poultry and cats. All remaining poultry (n = 17) were culled as part of control measures. Subsequently, an additional symptomatic cat tested PCR-positive and was euthanised. The PCR-positive symptomatic cats presented with diverse clinical manifestations, including neurological signs, respiratory symptoms and general sickness.
(SNIP)
This event highlights several important aspects:
Firstly, early detection through veterinary surveillance, including animal welfare inspections, can facilitate timely identification of outbreaks in backyard poultry holdings.
In this investigation, initial veterinary visits triggered further diagnostic testing after unexplained animal deaths were observed. Secondly, infections in mammals may occur during poultry outbreaks, and cats in particular can serve as indicators of substantial environmental virus circulation. The detection of HPAI A(H5N1) infection in several domestic cats on the affected premises demonstrates the potential for cross-species transmission under outbreak conditions.
Such spillover events have increasingly been reported and point to an evolving host range of HPAI A(H5N1) viruses [3,4,14]. Serum samples, obtained from all surviving cats, were seropositive for H5-specific antibodies analysed by a commercial ELISA which suggests a close epidemiological link between poultry and feline infections, although the role of cat-to-cat transmission remains unclear.In this investigation, evidence of predation or scavenging (e.g. poultry carcasses with bite marks) suggests that infection in cats may have occurred through direct contact with infected birds.
Finally, occupational exposure among first responders and veterinary personnel remains an important pathway for potential zoonotic transmission [1,4,14]. Several individuals involved in the initial response had unprotected contact with animals before confirmation of the outbreak.
(SNIP)
Conclusions
The detection of HPAI A(H5N1) in poultry and domestic cats in Sigmaringen district highlights ongoing zoonotic risks associated with HPAI outbreaks. Rapid interdisciplinary collaboration enabled early identification of the outbreak and implementation of targeted preventive measures.
Overall, this outbreak illustrates the importance of timely coordination between veterinary and public health authorities, early risk assessment of exposed individuals, and implementation of preventive measures within a One Health framework. Appropriate use of PPE, diagnostic testing, and prompt reporting of suspected cases are essential to prevent unprotected exposures and facilitate coordinated investigations. Continued vigilance and coordinated One Health surveillance remain essential to mitigate zoonotic transmission.(Continue . . . )
While much of the world's attention remains focused on the impact of HPAI on large commercial poultry farms - which are arguably better prepared to deal with HPAI outbreaks than small holders - there are more than 11 million backyard poultry flocks in the United States, and tens of millions more in Europe and Asia.
The USDA has reported well over 200 backyard flocks infected since September of last year in the United States, and we've seen at least one death `linked to contact with backyard or wild birds'.Last October, in UF/IFAS Extension: What Backyard Flock Owners Need to Know about Bird Flu (Influenza H5N1), we looked at two H5N1 related publications; one for backyard poultry owners, and another for consumers of poultry products and milk.
Finding ways to instill better biosecurity practices - and encourage personal protection (vaccination, PPEs, etc.) - before next fall's all-but-inevitable return of avian flu, could go a long way in reducing zoonotic risks.
Because as bad as HPAI has been up till now, it could become a lot worse in the future.
