What it looks like
Labored or rapid breathing — Bird breathes heavily, takes shallow breaths, may open mouth to breathe
Wheezing or crackling sounds — You hear rattling or crackling sounds when bird breathes; worse when bird is active
Lack of appetite — Bird refuses feed and water; sits away from feeders and drinkers
Diarrhea — Watery, greenish, or pale droppings; soiled vent and feathers
Lethargy and depression — Bird is inactive, fluffed up, and unresponsive; stays in corner or nest
Jaundice (yellowing of skin) — Pale, yellow, or discolored skin visible on face, legs, and vent area (often seen in inclusion body hepatitis form)
Swollen liver (hepatomegaly) — Abnormally enlarged liver visible during necropsy; possible causes sudden death
Stunted growth — Young birds fail to grow normally; smaller and weaker than unaffected flockmates
Likely causes
What to do
No specific antiviral treatment exists. Provide supportive care: nutritious feed, clean water, warm shelter, and isolation from other birds. Remove affected birds from the flock if possible to slow spread. Most birds recover if secondary bacterial infection is prevented with good management; however, birds may remain carriers.
When to see a vet
See a vet if your bird shows severe signs or doesn’t improve within a few days of treatment.
Prevention
Maintain good biosecurity (isolate new birds for 2-3 weeks before mixing with flock). Ensure adequate ventilation to reduce dust and respiratory irritation. Avoid live bird markets or buy from certified disease-free sources when possible. Minimize stress through proper housing, temperature control, and avoid sudden changes. Clean and disinfect equipment regularly.
FAQ
Is adenovirus infection the same as Newcastle disease or avian influenza?
No. Adenovirus causes milder respiratory disease than Newcastle disease or avian influenza. However, the symptoms overlap, so get a veterinary cause if you see sudden respiratory illness in your flock. Your vet can test to identify which virus is present and recommend appropriate steps.
Can I treat adenovirus with antibiotics?
Antibiotics don’t kill viruses; they only work against bacteria. However, if a secondary bacterial infection develops (which can happen when adenovirus weakens the bird’s immunity), antibiotics may help prevent pneumonia or air sacculitis. Your vet can assess whether antibiotics are needed.
If my bird gets over adenovirus, is it immune?
Recovered birds develop immunity to that specific virus serotype, but there are many types of avian adenovirus. Recovered birds may also become carriers and shed virus to other birds for months, even after they look healthy. Good separation helps prevent spread.
Is there a vaccine for avian adenovirus?
Commercial vaccines for adenovirus are not widely available in the U.S. Prevention focuses on biosecurity and good management practices. Some flocks may use experimental vaccines in research settings, but ask your veterinarian about your options for your specific flock.
What is inclusion body hepatitis?
Inclusion body hepatitis (IBH) is a form of adenovirus infection that affects the liver severely, especially in young birds. It causes jaundice, sudden death, and is more likely to kill chicks than adults. Keep young chicks warm, fed well, and away from sick birds to reduce risk.
For more help, try our chicken symptom checker or read about signs your chicken is sick.