Protecting Dairy Farms: Insights from Bird Flu Outbreaks
Published on February 8, 2026
The emergence of H5 avian influenza, commonly known as H5 bird flu, poses significant risks not only to bird populations but also to wildlife and livestock globally. A recent outbreak among dairy cattle in the United States serves as a crucial reminder for Australian farmers about the importance of ongoing vigilance.
Initially detected in US dairy herds in 2024, this virus resulted in considerable health issues and production declines within affected farms, as well as illness among some dairy farm workers who were exposed. Since its discovery, the virus has spread to 18 states, impacting over 1,000 dairy herds.
The unprecedented transmission of the virus from birds to dairy cows has offered valuable insights into its behavior within cattle and the potential pathways for its spread through dairy operations. Fortunately, Australia remains free from this particular strain of H5 bird flu, with the current risk to its dairy industry assessed as low. However, the experiences observed overseas provide essential lessons that can enhance preparedness efforts.
In light of the evolving global circumstances, the Australian Federal Government, in collaboration with state and territory authorities and industry stakeholders, has taken proactive steps to bolster national readiness. This includes strengthening surveillance systems, improving coordination among animal, wildlife, and human health agencies, and making targeted investments.
For the dairy sector specifically, the Department of Agriculture, Fisheries and Forestry, alongside Dairy Australia, commissioned an independent risk assessment to envision what a potential spillover event might entail under Australian conditions. The findings, recently shared with farmers and industry professionals through a webinar led by Dairy Australia, presented a comprehensive, evidence-based analysis of risks and preparedness strategies tailored for Australian farms.
The assessment concluded that while the risk of H5 bird flu entering the Australian dairy herd is low, should it occur, the likelihood of spreading between farms is also minimal. Further research is needed to fully understand the factors influencing H5 bird flu transmission in cattle, but it appears that lower farm density and reduced routine movements of cattle may contribute to this diminished risk.
Australia benefits from a unique advantage of being forewarned; unlike the US outbreak, which took authorities by surprise, Australia can prepare and implement control measures at an early stage.
If H5 bird flu were to reach Australia through bird migration, it is vital for dairy farmers to be alert to clinical signs of infection. In the US, infected herds consistently exhibited several symptoms, including a sudden decrease in milk production, abnormal thickening of milk similar to severe mastitis, fever, and lethargy. While mortality rates among cattle have remained low, the morbidity has been significant, with many cows suffering clinical ailments and requiring weeks or even months to return to normal production levels.
Preventive Measures for the Australian Dairy Industry
Insights drawn from the US outbreak underscore several straightforward measures that can be implemented to avert the introduction and spread of H5:
Animal Movements: When purchasing animals or moving them between farms, implementing quarantine protocols and observation periods before integrating new cows into the milking herd can significantly reduce exposure risks. In the US, authorities have introduced testing protocols for cattle movements and bulk milk screening to further mitigate these risks.
Milking Hygiene: Maintaining strict milking hygiene is crucial in herds where infections are suspected or confirmed. Milking affected or potentially infected cows last, or separately if feasible, can help limit the transmission through milking equipment. Additionally, careful handling of mastitic milk, thorough cleaning of equipment, and consistent preparation of teats are all essential practices.
Minimizing Milk Aerosols: Another practical measure involves reducing airborne milk droplets, which can be generated when high-pressure washing spills. Utilizing lower-pressure wash-down methods and minimizing splashing can decrease the potential for exposure.
Protecting People: Good biosecurity also encompasses protecting farm workers. Wearing gloves during milking and when handling milk or sick animals, washing hands thoroughly after glove removal, and managing potentially contaminated clothing are all effective strategies. Encouraging seasonal flu vaccinations can further reduce the rare chance of dual infections.
Surveillance and Reporting: Farmers' observations and instincts play a critical role in surveillance. Any unusual clusters of mastitis-like illnesses, sudden drops in milk production, or unexplained bird fatalities should prompt immediate consultation with veterinary professionals.
In summary, effective preparedness hinges on fundamental principles. Establishing and maintaining an up-to-date biosecurity plan is the cornerstone of safeguarding the dairy industry against potential threats.
- Andy Hancock, Dairy Australia
Updated February 8, 2026 3:00 PM | Just moments ago.
