The US Avian Flu outbreak: the impact on producers, manufacturers and processors
Posted by Greer McNally on
Topics: Animal Welfare, avian flu, WOAH
Posted by Greer McNally on
Topics: Animal Welfare, avian flu, WOAH
On April 1, US authorities confirmed a highly pathogenic strain of avian influenza (HPAI) had been transmitted to a person via livestock.
The case in Texas marks the second time in recent years that someone has contracted the viral disease in the US – after a poultry worker fell ill in Colorado in April 2022 – but the first time it has been transferred via infected dairy cattle.
The discovery followed an investigation launched by the U.S. Department of Agriculture, Food and Drug Administration (FDA) and Centers for Disease Control and Prevention (CDC) in March after detection of HPAI in cattle herds across Kansas, New Mexico, Michigan and Idaho as well as Texas.
The seriousness with which US authorities are responding to the handful of cases detected so far – with 16 herds currently affected - is unsurprising. Left unchecked, outbreaks of avian influenza can pose significant risk to animal health as well as livelihoods and global supply chains.
For producers, manufacturers and processors it’s therefore critical to develop their understanding of the disease and take steps to mitigate the risk to their own business.
Avian influenza is the umbrella term used to describe a group of influenza strains typically found among aquatic wild birds. These strains can be highly contagious and affect the respiratory, digestive and/or nervous system of affected animals. Though they originate in wild bird populations, avian influenzas can also spread to farmed birds. There has also been some limited transmission to humans though public health risks are low.
The complex disease can be divided into multiple subtypes, each with different genetic characteristics and different rates of prevalence. One such example is the influenza A virus subtype A(H5N1). The first outbreak of this strain was detected in farmed geese in southern China and Hong Kong in 1996 and led to 18 recorded human infections, six of which would be fatal. The response from authorities was to slaughter some 1.6 million chickens at wholesale facilities or vendors within the city state and place a temporary ban on the import of chicken from neighbouring areas.
There have been numerous reported outbreaks of avian flu since, with many of the most prolific taking place in the last five years. In the US alone, more than 49 million birds in 46 states have either died because of bird flu virus infections or have been culled due to exposure to infected birds since early 2022, say the CDC. So far in 2024 the USDA has found bird flu in eight commercial flocks and 14 backyard flocks, affecting 530,000 poultry, according to agency data.
The knock-on impact to livelihoods and global food supplies has been severe, with the economic cost to US suppliers ranging from $2.5bn-$3bn, according to a report by FAIRR. The outbreaks have also contributed to the inflation of food prices, with the cost of a dozen eggs in the US more than doubling from 2021 to 2022 as a direct result, according to the investor network. This continued in 2023 with prices up by 40% because of a resurgence of detected cases.
Early detection and timely reporting are the best way to mitigate the risks of avian flu and curb an outbreak in its early stages.
As per World Organisation for Animal Health (WOAH) regulations, US authorities must report any detection of:
Strict biosecurity measures and surveillance can also be implemented at the animal source by producers to slow the spread. Prior to infection, this includes keeping poultry away from contact with wild birds, ensuring high standards of hygiene in housing, equipment and feed, and reporting any bird illnesses or deaths to local veterinary services.
Once an infection has been detected, producers may undertake a policy of culling infected animals or those in close proximity to rapidly contain and control the disease.
In the US, where a flock is infected with HPAI, the Department of Agriculture (USDA) will provide indemnity and compensation to mitigate some of the losses and costs incurred. This includes any birds or eggs that must be destroyed, though it does not extend to birds that have died as a result of infection.
Under certain conditions, authorities may recommend that poultry are vaccinated but this should be implemented as part of a wider strategy to prevent infection, rather than in isolation. The USDA is currently working on a vaccine tailored to the current strain of bird flu detected and hopes to be in a position to distribute to producers within 18 months.
Global campaign groups, such as Compassion in World Farming, have urged authorities to go further in their response to outbreaks, however. They’ve called for the mass vaccination of flocks to slow the spread, as well as a radical restructuring of the poultry and pig farming sector that would see a transition to smaller farms, more disparate production facilities and a greater diversity of breeds to integrate resilience.
The first confirmed case of cross-contamination between cattle and a human in the US could see control measures targeting avian flu extend beyond its current focus on farmed birds. Dairy farms, which are typically open air and thus exposed to wild birds, may find it more challenging to implement the types of biosecurity and biocontainment measures that have become commonplace in poultry supply chains, adding potential cost and complexity for the sector.
The resurgence of highly pathogenic strains of avian flu in the last five years has already cost food producers, processors and manufacturers millions in lost revenues and opportunities, alongside its risk to animal health. But things are looking up. With the UK now declared HPAI-free in poultry in line with World Organisation for Animal Health (WOAH) rules, it is a sign that the industry is gaining more ground in its fight against the virus.