On May 1, Iowa governor Terry Branstad declared a state of emergency to address the rising toll that avian influenza is taking on the state’s poultry industry. Since December 2014, there have been several reports of highly pathogenic avian influenza (HPAI) infections in U.S. domestic poultry (both backyard and commercial flocks), captive wild birds, and wild birds in the United States. There have been no human cases.
There are many strains of avian influenza (AI) worldwide, and they can be classified as either highly pathogenic or low pathogenic (LPAI) based on the severity of the illness they cause. The risk of human infection is low, even with the highly pathogenic strains. Most human infections with AI viruses (including Asian HPAI H5 viruses and LPAI H7N9 in China, which were both widely publicized) occurred in people who had direct contact with either infected birds or the excretions/secretions of infected birds. Nonetheless, human infection is possible, so the Centers for Disease Control and Prevention (CDC) has developed guidelines which can be found on their page about H5 viruses in the United States.
U.S. HPAI H5 avian viruses in wild birds were first detected in Washington State in December and additional infections with HPAI H5N2, H5N8, and a reassortant H5N1 viruses have also been reported in the Pacific flyway. By late April 2015, there were also confirmed cases of HPAI viruses in commercial turkey flocks or backyard flocks in Minnesota, Iowa, South Dakota, Wisconsin, North Dakota, Montana, Arkansas, Missouri, Kansas, Oregon, California, Washington, and Idaho. Ongoing updates on new cases being confirmed by the Department of Agriculture (USDA) can be found on their site about avian influenza disease.
With regard to preparedness, CDC is currently studying domestic HPAI H5 virus samples to assess for antiviral susceptibility and look for genetic markers or evidence associated with greater disease severity, transmissibility, or other characteristics.
About Christina Baum
Christina Baum serves as a Program Analyst for NACCHO’s Infectious Disease Prevention and Control program.
