Search begins for source of deadly new bird flu strain
U.S. officials, poultry farmers scramble to stop its spread
MINNEAPOLIS— Animal health experts and poultry growers are scrambling to determine how a dangerous new strain of bird flu infected turkey flocks in three states — and to stop it from spreading.
Avian influenza is common in wild migratory waterfowl but doesn’t usually harm them. But the H5N2 strain is deadly when it spreads to commercial poultry. It can wipe out a flock of tens of thousands of birds in a few days, as it did at a farm last month in Minnesota, the nation’s top turkey-producing state. The same strain soon turned up on two farms in Missouri and one in Arkansas.
The vast majority of turkeys and chickens in the U.S. spend their lives confined indoors to protect against disease. Yet, as the infections show, viruses can still reach them — tracked in by humans or rodents; carried on trucks, equipment, crates and egg flats; passed from waterfowl to shore birds that find their way into a barn. “This new guy is a bad actor,” said Dr. Carol Cardona, an avian influenza specialist at the University of Minnesota.
Minnesota confirmed its outbreak March 4, the first H5N2 found in the Mississippi flyway, a major bird migration route. The Missouri and Arkansas cases were confirmed this week. The only known commonality is the flyway. Why it showed up at these locations simultaneously is a mystery, though Cardona and other experts suspect waterfowl or other wild birds.
Meanwhile, officials are keeping an eye on the workers who had contact with the infected flocks, and producers are tightening their standard biosecurity measures, which include putting on sanitary clothing and showering on their way in and out of barns.
The new strain — along with other recent outbreaks of highly pathogenic strains in commercial turkey and chicken farms, backyard flocks and wild birds in the Northwest’s Pacific flyway — also affects the industry’s bottom line in the affected states. Dozens of countries have banned poultry imports from affected states, a common practice done mainly to protect their own flocks.
The World Health Organization says avian influenza viruses can survive in contaminated raw poultry, so it’s possible to spread them via fresh or frozen products. But government and industry officials say the danger to humans is very low, and people can’t catch it from properly cooked poultry or eggs. Cardona said the likelihood of bird flu entering a country through imported products is “very, very low.”
Minnesota, Missouri and Arkansas followed rapid response protocols from the federal government and poultry industry. The goal is to “keep what’s in the barn in and what’s out of the barn out,” said Steve Olson, executive director of the Minnesota Turkey Growers Association and the Chicken and Egg Association of Minnesota.