Chicken flock, wild bird infections linked to HPAI

Robert Nathan Gregory

STARKVILLE, MISSISSIPPI

The Mississippi Board of Animal Health reported Feb. 23 that a backyard poultry flock in Copiah County tested positive for highly pathogenic avian influenza, often referred to as HPAI or H5N1.

This is the second backyard flock to test positive for HPAI. The first confirmation was in Lowndes County in November 2022. There have also been two detections in commercial broiler flocks, one in Lawrence County in November 2022 and the other in Leake County in February. All affected facilities were quarantined, and the birds were depopulated to prevent spreading.

Poultry growers are encouraged to report sudden deaths in their birds.

HPAI is a highly contagious form of avian influenza that can kill entire flocks of infected poultry. The virus can occur naturally in wild birds and can be spread to poultry. There has been a rash of wild bird die-offs attributed to this disease.

Many wild birds, especially waterfowl, can be infected by HPAI and not show symptoms. However, since December 2022, the Animal and Plant Health Inspection Service, a division of the U.S. Department of Agriculture, has reported more than 150 wild bird fatalities related to HPAI in Mississippi. Many of the fatalities have been in black vultures and snow geese.

“Eighty-four percent of the analyzed U.S. detections in poultry premises and nonpoultry flocks are consistent with independent wild bird introductions,” said Dr. Jim Watson, state veterinarian. “The flyways of the Mississippi, Pearl River and Tombigbee rivers seem particularly affected. This means that the virus is in the environment in most of our poultry producing counties.”

HPAI prevention involves strict biosecurity measures from producers. Watson encouraged growers to secure poultry houses so wild animals have no points of entry. He also recommended that poultry producers have clothing and footwear exclusively for use in the houses.

Jessica Wells, poultry specialist with the Mississippi State University Extension Service, said preventing indirect contact is just as important as protecting houses from direct transmission.

“When the threat level to backyard and commercial flocks is heightened by the spread of an avian virus, keeping visitors away from your birds and cleaning feeders and houses is a must,” Wells said. “You should clean and disinfect feeders every day and disinfect all poultry equipment before and after use. Everyone who enters poultry houses needs to be using footbaths, and you should change those baths regularly.”

Other measures include using sound deterrents to keep wild birds from roosting near poultry house areas and covering vents and openings in poultry house pens with narrow-mesh wire screen to keep wild birds out.

The virus does not pose a food safety risk. All poultry products should be cooked to an internal temperature of at least 165 degrees before they are safe to eat.

Backyard bird owners can report any sick or dying birds online at https://hpai.ms.gov/ or by calling the Mississippi Board of Animal Health animal disaster hotline at 1-888-646-8731. 

MSU Extension Information Sheet 2015, “Biosecurity Measures to Combat Avian Influenza Threat,” is available at https://tinyurl.com/ysscv8j2. Read more about HPAI causes, transmission and symptoms at https://extension.msstate.edu/avian-flu.  ∆