The commercial turkey industry in Minnesota has been hit hard by the current HPAI outbreak. Could this been

prevented? Is the USA prepared for large-scale outbreaks of Avian Influenza?

Does the United States have the strongest AI surveillance program in the

world, as claimed on the website of USDA APHIS? If so, how come that the current outbreak was detected in Canada, weeks

or even longer before the first outbreaks within the poultry population were detected just on the other side of the border in the US? And why doesn’t the AI surveillance program include large-scale active field surveillance within the wild birds population? Why took it so long before the potential impacts associated with the introduction of HPAI viruses into wild bird populations were understood by the industry? Time to analyze what happened in the past 6 month in North America.

The question what caused H5N2 spread throughout the US and Canada is currently heavily debated. One thing is clear: the outbreak in North America stayed under the radar for too long. Although the OIE report of December 3, 2014 suggested that suggests that the outbreak of high path H5 from wild birds began at the end of November, with high mortality on December 1, the confirmation came first on December 6, 2014, after the poultry on 5 commercial farms were culled.

Although all farms were located to close to the Canadian/US border, USDA APHIS confirmed the first commercial case of H5N8 on January 23, 2015. Before that date,

outbreaks in the USA occurred to be only in wild birds and in backyard holdings. Since the first outbreak until April 16, 2015, more than 3 million birds are culled on 10

backyard holdings and 40 commercial farms in the USA. Important detail: 38 out of 40 farms were commercial turkey farms; 25 of the infected commercial farms are located

in Minnesota. Lets focus on the current outbreak under turkeys on commercial farms in Minnesota.

Minnesota is currently ranked as USA #1 for turkey production state, and is home to the world’s largest turkey hatchery company (Willmar Poultry Company) as well as the 2nd

largest turkey processing company in the U.S. (Jennie-O Turkey Store). Minnesota's turkey farmers raise approximately 46 million birds annually: approximately 450 turkey

farmers who operate 600 turkey farms. The question is: how did the farms in Minnesota have gotten infected with HPAI? And is passive surveillance the best tool to predict

further spreading?

The current 25 infected commercial farms in Minnesota are signaling a profound

surveillance failure in the USDA APHIS surveillance system. The current surveillance

program in the USA is mainly based on active laboratory surveillance of commercial flocks. The United States claims to have the strongest AI laboratory surveillance program in the world. The USDA along with poultry industry partners is actively looking for the disease. In Minnesota, the Board of Animal Health immediately quarantines potentially infected flocks and collects samples for AI testing.

Once a flock confirmed positive, the Board and the USDA work with the producer/bird

owner to create a flock plan. The plan includes appraisal, indemnity and depopulation of remaining birds, carcass disposal and cleaning and disinfection of the premises.

Although active laboratory surveillance is the most important tool to allocate outbreaks in a very early stage, it is not enough: Active surveillance under wild birds is absolutely

needed, including virus isolation, and –isolation, in order to analyze the risk of the H5N2 virus becoming endemic in the North American wild bird populations.

Active surveillance in the USA mainly depends on findings from hunter-killed wildfowl. This limits the active surveillance to the periods that hunting is allowed. Outside these hunting periods it is not possible to find sufficient reliable epidemiologic data. The only data is coming from dead bird collection and from examining droppings in wetlands etc.

In Minnesota migrating birds were not tested because of claims of no such birds because free water was limited (in Minnesota, the “land of 10,000 lakes”). A helicopter tour (after confirmation) of the area identified resident ducks and 148 fecal samples were collected and 2 were influenza A positive (1.35%), This low frequency raises serious questions about the quality of the samples, and the likelihood of detecting Fujian H5 in 2 influenza A positive samples is very small.

Conclusion The current epidemiologic efforts are insufficient to determine the risks of other farms getting infected, because the mechanism of infection the current flocks is still unknown.

Active laboratory surveillance is not the answer either to predict future outbreaks: Massive efforts in active field-based epidemiologic research under wild birds and in

wetlands are needed to as part of an early warning system; hunting, fishing and other

activities that take place in the wetland areas have to be banned to prevent humans to enter the HPAI infection to the farm; and all commercial turkey farms need to be completely isolated as long as the risks of outbreaks is eminent. Compared to other poultry species, turkeys need only 1/100 of the normal virus load on contaminated

materials (soil, organic materials etc.) to become infected, with lethal consequences for the birds, and enormous financial consequences for the farming industry.

The turkey industry is still completely in the dark about the current outbreak situation. The USDA APHIS active laboratory surveillance programs might be one of the best in the

world, is clearly not enough under the current circumstances to determine whether a flock has become infected. Unless the efforts to collect more valid data is substantially

increased, followed by rigorous epidemiologic analysis and a solid risk assessment, the

turkey industry in Minnesota will probably see more outbreaks to come in the near future.

Confirmed outbreaks in the USA, from December 19, 2014 until April 16, 2015: