Avian aspergillosis
Aspergillosis is a disease caused by a microscopic fungus very common in the environment, called Aspergillus. This fungus thrives in decaying organic matter, damp straw, moldy hay or poorly maintained bedding. In the buzzard (Pernis apivor...
What is it?
Aspergillosis is a disease caused by a microscopic fungus very common in the environment, called Aspergillus. This fungus thrives in decaying organic matter, damp straw, moldy hay or poorly maintained bedding.
In the buzzard (Pernis apivorus), a migratory raptor which feeds mainly on wasp and bee larvae, this disease mainly affects the respiratory tract: air sacs, lungs, sometimes trachea.
It is a common condition among wild raptors collected in care centers, particularly after significant stress, transport or prolonged captivity.
Key point
Potentially serious illness, particularly in weakened or newly captured wild birds, where progression may be rapid to severe respiratory distress.
Commonly observed signs
These signs are neither exhaustive nor specific. Only a veterinarian can establish a diagnosis.
Related signs — each one links to its page:
The signs are often subtle at first, making the disease difficult to spot early.
The bird may experience faster or more difficult breathing, sometimes accompanied by an abnormal sound while breathing.
He becomes despondent, eats less and gradually loses weight.
His behavior changes: he remains prostrate, moves less, can stay away.
In advanced forms, respiratory distress becomes visible, with the bird opening its beak to breathe and showing obvious signs of extreme fatigue.
When to consult without delay
This list does not replace veterinary advice. It gathers situations that justify a prompt consultation.
Causes and risk factors
The disease is caused by fungi of the genus Aspergillus, most commonly Aspergillus fumigatus. This fungus releases microscopic spores into the air which are inhaled by the bird.
In a healthy individual, these spores are generally eliminated without problem by the immune system. The disease mainly occurs when the bird's defenses are weakened.
Stress plays a major role: capture, transport, injury, captivity in a care center.
An immune system weakened by another illness, poisoning or malnutrition favors infection.
A humid environment, moldy litter and poor ventilation of aviaries increase the risk of exposure to spores.
Young birds or individuals already weakened by trauma are particularly vulnerable.
Migration, a physiologically demanding period for the flock, can also represent a weakening factor.
Transmission
The disease is not contagious from one bird to another. Contamination occurs only by inhalation of spores present in the environment, never by direct contact between individuals.
Diagnosis and care
Diagnosis is the veterinarian's responsibility, based on clinical examination and laboratory tests. Care is decided case by case.
The veterinarian relies on the history of the bird (recent capture, stress, injury), the clinical examination and additional examinations.
An air sac endoscopy often allows direct visualization of characteristic lesions.
Blood tests, a test for specific antibodies or antigens, and x-rays can help guide the diagnosis.
The definitive diagnosis is based on the detection of the fungus, by culture or analysis in a specialized laboratory.
Treatment
Treatment is based on antifungal medications, administered under strict veterinary supervision, often over a prolonged period.
Supportive care is essential: stress reduction, oxygen therapy if necessary, nutritional support.
Treatment generally requires hospitalization in a center specializing in wildlife.
Treatment depends on the cause and the animal's condition: it must be determined by a veterinarian. No self-medication.
Prevention
Maintain clean, dry bedding in aviaries or convalescent cages.
Ensure good ventilation of accommodation premises.
Avoid storing moldy hay or straw near birds.
Minimize stress when handling and transporting collected wild birds.
Monitor the general condition of weakened or recently captured birds, as they are the most at risk.
Possible complications
If left untreated, the infection can spread widely into the air sacs and lungs, causing severe respiratory distress.
Complications can affect other organs if the fungus spreads.
The disease can be fatal, especially in an already weakened bird.
When to see a veterinarian
The bird is breathing faster or harder than normal.
An abnormal noise accompanies his breathing.
The bird remains prostrate, refusing to move or feed.
Weight loss or depression sets in without an obvious cause.
Any wild raptor collected must be presented promptly to a treatment center or a wildlife veterinarian.
Prognosis
The prognosis strongly depends on how early the diagnosis is made. Detected early, the disease can be treated with reasonable chances of recovery.
Diagnosed late, once the lesions have spread, the prognosis becomes guarded to bleak, particularly in a wild bird already weakened by capture or injury.
Frequently asked questions
Can buzzard aspergillosis infect other birds?
No, it is not a contagious disease between birds. It only results from the inhalation of spores present in the environment, not from contact with a sick animal.
Why are honeybees collected in health centers at risk?
The stress of rescue, transport and captivity weakens the bird's immune defenses, which facilitates the development of the fungus already present in its environment.
How to recognize the first signs in a raptor?
The signs are often discreet: slight change in behavior, breathing a little faster, less appetite. This is why any abnormality in a collected wild bird must be reported quickly to a professional.
Is aspergillosis a common disease in wild raptors?
Yes, it is one of the most common conditions encountered in wildlife care centers, particularly in birds stressed or weakened by injury.
References
WOAH — Organisation mondiale de la santé animale (ex-OIE)
AVMA — American Veterinary Medical Association
Content reviewed by the TunisieVet editorial team · Updated 29 September 2026
Comments (0)
No comments yet.
AT A GLANCE
Need a veterinarian?
Find a practitioner near you on TunisieVet, with their specialities, hours and contact details.
Find a veterinarianCategories
Affected species
This information is provided for educational purposes only and is not a substitute for a veterinary consultation. If you have any concerns about your animal's health, consult a veterinarian.
Thinking of welcoming a pet? Dogs and cats are waiting for a family in Tunisia, and adoption is completely free.
Adoption listingsTo discover
Related diseases and linked Animalia content.
Avian botulism
Bacterial
Bumblefoot (raptor pododermatitis)
Bacterial
Parasitism by raptor ectoparasites (mallophages and mites)
Parasitic
Gastrointestinal helminthosis of common buzzard
Parasitic
TunisieVet in your pocket 📱🐾 Access your veterinary services wherever you are. [ Download the app ]
Learn more