New Zealand’s H7N6 Case: A Call to Fortify Biosecurity

New Zealand has long been a global model for biosecurity, but the recent detection of the H7N6 avian influenza strain has highlighted the critical importance of vigilance and swift action. This is the first instance of H7N6 being found in the country, marking a significant moment in its biosecurity efforts.

What is H7N6

H7N6 is a subtype of the avian influenza virus that affects poultry and wild birds, leading to significant agricultural and economic consequences. While not as extensively studied as other subtypes, H7N6 has been associated with outbreaks in various regions, causing concern within the poultry industry.

Transmission and Control Measures:

H7N6 can spread through direct contact with infected birds, contaminated equipment, and, now, possibly through wild bird populations. Control measures include strict biosecurity protocols, culling of infected flocks, movement restrictions, and surveillance to monitor and prevent the spread of the virus. Outbreaks of H7N6 can lead to substantial economic losses due to decreased poultry production, trade restrictions, and increased costs associated with control measures. The rapid spread and high mortality rates in poultry necessitate prompt and effective responses to mitigate these impacts.

Understanding the behaviour and impact of H7N6 in agricultural settings is crucial for developing effective prevention and control strategies to protect both animal health and economic stability.

What Happened in New Zealand?

• The outbreak was confirmed at a commercial free-range egg farm.
• The government imposed strict biosecurity measures, including:
• Movement controls on poultry and associated products.
• Depopulating infected birds.
• Creating buffer zones to prevent the virus from spreading.

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Food Safety and Public Health

While the outbreak is concerning, health officials assured the public that H7N6 poses minimal risk to humans and does not affect food safety. Properly cooking eggs and poultry remains essential, with guidelines suggesting eggs be cooked until the whites and yolks are firm and poultry reach an internal temperature of 75°C for at least 30 seconds.

Origins and Spread

The H7N6 virus is believed to have mutated from a low-pathogenic strain originally introduced by wild waterfowl. Thankfully, it does not seem to spread back to wild bird populations, which limits its transmission potential compared to highly transmissible strains like H5N1.

New Zealand is renowned for its strong biosecurity measures, which include comprehensive annual testing of around 2,000 wild bird samples to monitor for low-pathogenic avian influenza strains. Additionally, the country’s geographic isolation provides a critical advantage, enabling early detection and swift response to outbreaks, minimizing the risk of widespread impact.

Strengthening Biosecurity on Farms: A Practical Checklist

The H7N6 incident highlights the need for farmers to enhance their biosecurity practices. Here’s a checklist with an emphasis on high-risk areas:

Ventilation (Air Control):

• Seal all vents to prevent entry of wild birds.
• Implement a robust vermin control program.

Biosecurity Lock (Personnel)

• Each birdhouse or group of birdhouses should be treated as isolated pods. To ensure proper separation, clearly defined physical step-overs must be established immediately at all entry and exit points.
• Boots: Outdoor boots must never be introduced to the flock area and should not cross the step-over from "dirty" (outside) to "clean" (inside). Similarly, boots designated for the clean area must not cross into dirty zones. This is the essence of the “dirty-clean approach.”
• Foot Baths: Before entering the dirty area, all incoming boots must pass through a foot bath containing a disinfectant approved by local authorities for notifiable diseases. Always step directly from the foot bath into the dirty area. Foot baths should be replenished daily with fresh disinfectant to maintain efficacy.? Boots should remain wet within the footbath to ensure the contact time is reached following the IFUs of the specifically used disinfectant.

These measures are critical to minimizing the risk of pathogen transfer and protecting the flock.

Visitor Protocol

• Limit access to essential personnel only.
• Train staff on “clean-dirt” boot practices and protocols.

Vehicles

• Disinfect all vehicle wheels upon entry.
• Provide disposable gloves and boot covers for visitors.

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Water Management:

Water management on farms is often an overlooked yet critical aspect of biosecurity. A single heavy downpour can contaminate a farm’s well water with dangerous pathogens, such as those carried in the faeces of wild birds. Waterfowl, which are highly resistant to many pathogens, act as reservoirs within the wild bird ecosystem. This contamination can bypass biosecurity measures, exposing an entire flock to devastating diseases. To combat:

• Ensure incoming water is disinfected to eliminate pathogens.
• Continuous water disinfection methods, such as Aquatabs, should be used to prevent contamination.

Given that water is the most consumed nutrient in a bird's life, it is essential to ensure its safety from source to consumption. This can be effectively achieved using products like Aquatabs InLine, which add an extra layer of biosecurity by disinfecting water and closing a long-standing gap in farm biosecurity practices. Continuous water disinfection, 24/7, is not just recommended but vital to safeguarding flocks and maintaining farm health. See for yourself the ease with which the Aquatanbs InLine can be implemented into your biosecurity programme here

The Bigger Picture: Lessons from H7N6

This outbreak demonstrates the critical importance of swift action and collaboration across industries and government bodies. It serves as a powerful reminder that early detection, preparedness, and adherence to stringent biosecurity measures are essential for safeguarding public health and vital industries like agriculture.

Farmers, health officials, and communities all play crucial roles in upholding biosecurity standards. Such events highlight the need for vigilance and proactive responses to emerging challenges, setting a benchmark for effective biosecurity practices worldwide.

By addressing these concerns, societies can protect their people, industries, and environments, reinforcing resilience against future threats.

If you would like more information on biosecurity practices and protocols using our products, contact our agri-expert Shane Stephens

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