Defend the Flock

Bird flu and your backyard flock

Highly pathogenic avian influenza (HPAI) is a fact of life for anyone with birds in North America. You cannot make a flock risk-free, but a few cheap habits cut the odds a lot.

Cartoon illustration of a metal feed scoop overflowing with brown layer pellets beside leafy greens and dried mealworms

Why it matters

The U.S. Department of Agriculture's Animal and Plant Health Inspection Service (APHIS) describes HPAI as highly contagious: it can wipe out an entire flock in days. APHIS also reports that roughly 75% of detections are consistent with wildlife introductions, and waterfowl are among the most common carriers. Standing water and spilled grain attract sparrows and other birds that bring the virus close to your coop. Risk rises during spring and fall migration.

Open runs and spilled feed are exactly what bring wild birds close. For current detections, APHIS keeps a map of confirmed cases in commercial and backyard flocks.

Signs to watch for

APHIS's Defend the Flock program lists these signs of illness. Birds with HPAI may show one or more of them, and some die suddenly with no warning at all:

  • Sudden death
  • Lack of energy and appetite
  • A drop in egg production
  • Swelling of the eyelids, comb and wattles, and of the shanks
  • Purple discoloration
  • Coughing, sneezing, nasal discharge and gasping for air
  • Incoordination
  • Diarrhea

Because many of these also have ordinary causes, the rule is simple: if several birds are sick, or birds die suddenly, report it instead of guessing.

Who to call

If you see signs of illness, act right away. APHIS lists these places to report sick birds:

  • The USDA toll-free line: 1-866-536-7593
  • Your state veterinarian, or the state animal or poultry diagnostic lab
  • Your veterinarian
  • Your local Cooperative Extension office

Keep sick birds apart, avoid visiting other flocks, and ask the official what to do next. The University of Maryland Extension advises contacting your state veterinarian immediately if you see high mortality, and not visiting other farms or poultry events in the meantime.

Four habits that lower the risk

Defend the Flock groups its biosecurity advice into four steps:

Clean up. Disinfect equipment, tools and clothing before and after use. Keep feed, water and bedding clean. Wash your hands often.

Step up. Wear dedicated boots or shoe covers for chores, and use a footbath at the entry and exit of the run.

Divide up. Keep poultry separate from other animals. Use a covered run or netting to reduce contact with wild birds, and limit visitors.

Brush up. Check your flock every day and keep simple records, so a change shows up quickly. Make sure everyone who helps with chores knows the signs.

Two practical extras from University of Maryland Extension: quarantine birds returning from shows or fairs for 2–3 weeks away from the home flock, and remove and dispose of dead birds properly, following local guidelines. Our feeding guide covers rodent-proof storage and not leaving feed out overnight, which also cuts the wild-bird traffic around your coop.

Quick checklist

  • Cover the run with a roof or netting
  • Pick up spilled feed and fix standing water
  • Keep a pair of boots just for the coop
  • Store feed in sealed bins and never leave it out overnight
  • Quarantine any new or show birds for 2–3 weeks
  • Look over the flock every day
  • Save 1-866-536-7593 in your phone

Quick answers

What are the signs of bird flu in chickens?

Sudden death, low energy and appetite, a drop in egg production, swelling of the eyelids, comb, wattles and shanks, purple discoloration, coughing, sneezing, nasal discharge, gasping, incoordination and diarrhea.

Who do I call if my chickens are sick?

Call the USDA toll-free line at 1-866-536-7593, your state veterinarian or state diagnostic lab, your veterinarian, or your local Cooperative Extension office.

How can I protect my backyard flock from avian influenza?

Keep wild birds and their droppings away from feed, water and the run with a covered run or netting. Use dedicated boots, disinfect equipment, limit visitors, keep new birds in quarantine, and check your flock daily.

Sources

Last checked October 2026

This is general guidance, not veterinary advice. For a sick flock, call the numbers above. APHIS updates its guidance as outbreaks change.