1. Jacques Guillot, Guillaume Le Loc’h, Pascal Arné,
Françoise Féménia, René Chermette
Avian
aspergillosis
UMR INRA, AFSSA, ENVA, UPVM 956, Biologie Moléculaire et Immunologie Parasitaires
et Fongiques, Ecole Nationale Vétérinaire d’Alfort, 94704 Maisons-Alfort Cedex, France
2. Introduction
Aspergillosis is considered as one of the most
important infectious diseases in birds
• early 1800s: first observations
scaup duck, jay, bullfinch, bustard and several swans
• 1898: first cases in turkey poults (Lignières & Petit in France)
• Since then, cases in a very wide range of avian species…
3. 5 key questions…
Why are birds more susceptible than mammals ?
In which circumstances does aspergillosis occur in birds ?
Is it possible to make an early diagnosis in birds ?
Is it possible to treat or prevent avian aspergillosis ?
What do the main clinical signs and lesions look like ?
4. Susceptibility of birds
Birds are much more susceptible to aspergillosis than
mammalian species
• Environmental contamination by Aspergillus spp.
5. Susceptibility of birds
• Environmental contamination by Aspergillus spp.
• Avian anatomy and physiology
40-43°C
Birds are much more susceptible to aspergillosis than
mammalian species
lungs / air sacs
6. Susceptibility of birds
• Environmental contamination by Aspergillus spp.
• Avian anatomy and physiology
• Avian immunology
Lack of resident macrophages in airways and air sacs
Heterophils without peroxydation
Birds are much more susceptible to aspergillosis than
mammalian species
7. Epidemiology
Aspergillus fumigatus / Aspergillus flavus, Aspergillus niger…
Overgrowth
Specific virulence factors ?
humidity, dampness
drying period …
8. Epidemiology
• a 600 m2 confinement building in the Center of France
• a flock comprising 4500 turkeys
females slaughtered at the age of 12 w and males at the age of 16 w
Genotyping of environmental
and clinical A. fumigatus
isolates
(2 microsatellite markers)
Bart-Delabesse et al. J. Clin. Microbiol. 1998
An epidemiological survey was conducted in France
13. Epidemiology
362 air samples, 134 isolates
53 genotypes
16 week-sampling period
Lair-Fulleringer et al. Poultry Science 2006
14. Epidemiology
Aspergillus fumigatus / Aspergillus flavus, Aspergillus niger…
Overgrowth
Specific virulence factors ?
• Species
• Avian strains
• Individual susceptibility ?
• Age
• Sex
• Stress
• Other micro-organisms
• Toxicosis
• Therapeutics
captive environment
handling
migration…
mycotoxins ?
corticosteroids
turkeys, quails,
raptors, penguins,
parrots, waterfowl
15. Clinical signs and lesions
Different avian species
Different epidemiological situations Many clinical signs
Acute aspergillosis
= inappetance, depression, polydipsia, polyuria, dyspnoea, cyanosis
= sometimes, sudden death without any signs
Chronic aspergillosis
= signs are dependent on the area of invasion
change in voice
respiratory stridor
exercice intolerance
ataxia, torticollis, seizures
conjunctivitis, keratitis
beak malformation…
fatal evolution
16. Clinical signs and lesions
ENVA
Kaminski et al.
air sacculitis
Aspergillosis
of eggs
ENVA
21. Diagnosis
Serology
• Immunologically, birds respond to Aspergillus infection in
the same way as mammals and a type I response appears
most beneficial
• Birds also respond with specific antibody production
similar in its kinetics to mammals
• Serological tests that may be used in birds include the
detection of specific antibodies or fungal antigens
22. Diagnosis
Serology
detection of specific antibodies
False negative results
some birds may not be able to mount an appropriate response
some infection locations result in limited antigenic stimulation
Antibody titers not necessary correlated to clinical severity
High prevalence of seropositivity in captive penguins
Low prevalence of seropositivity in wild birds
24. Diagnosis
Serology
detection of galactomannan
Cray et al. ISHAM 2006 (poster P-0011)
839 serum samples (from suspected or confirmed cases)
Galactomannan in 50% of samples from penguins
in 25% of samples from other birds
Many chronic cases = negative for antibody but positive for galactomannan
But long term chronic cases = negative for both antigen and antibody !
25. Diagnosis
Serology
detection of galactomannan
Arca-Ruiba et al. Vet. Rec. 2006
90 serum samples (from cases in falcons)
182 control serum samples (from healthy falcons)
Galactomannan in 12% of samples from infected falcons
in 5% of samples from healthy birds
26. Diagnosis
Serology
detection of galactomannan
Le Loch’ et al. ISHAM 2006 (poster))
Platelia®
Aspergillus
+ -
CIE
+ 17 39 56
- 20 65 85
37 104 141
27. Diagnosis
Serology
detection of galactomannan
Many false negative results
variable release of GM
variable kinetics
according to avian species
according to physiological status of each bird
according to the level of immune complexing
Some false positive results
circulating GM from other fungi
cross reactivity with bacterial components (food supplementation ?)
30. Treatment
Falcons, parrots, wild birds in zoological or rehabilitation centers
Amphothericin B
Flucytosine
Ketoconazole
Itraconazole
Terbinafine
Voriconazole (Langhofer, AAV proc. 2004)
Radiography, endoscopy or serology for the follow up
+ Supportive therapy
+ Surgical debridement of the lesions
32. Prevention
• Reduction of fungal contamination
• Chimioprevention ?
Vaccination with a heat-killed culture filtrate preparation has been reported
to reduce mortality in ducks and waterfowl
• Reduction of stress
• Vaccination
Richard (1984) reduced mortalities by 50% in turkey poults vaccinated with
germinated A. fumigatus conidia
33. Conclusions
« Avian aspergillosis »
= not a single entity but a complex of several diseases…
• importance of prophylactic procedures
• poor prognosis
• need for specific avian models of aspergillosis
• variable epidemiological situations
• several diagnostic tools required
34. References
Cray, C., Rodriguez, M. & Watson, T. (2006) Aspergillus serodiagnostics in avian species. 16th Congress of the
International Society for Human and Animal Mycology (ISHAM), June 25-29th 2006, Paris (Poster).
Harmon, B. (1998). Avian heterophils in inflammation and disease resistance. Poultry Science, 77, 972-977.
Kearns, K.L. (2003). Avian aspergillosis. In: Recent advances in avian infectious diseases. Kearns KS, Loudis B
(Eds). Ithaca, International Information Service.
Klika, E., Scheuermann, D.W., De Groodt-Lasseel, M.H.A., Bazantova, I. & Switka, A. (1996). Pulmonary macrophages
in birds (barn owl, Tyto tyto alba), domestic fowl (Gallus gallus domestica), quail (Coturnix coturnix) and pigeon
(Columbia livia). Anatomy Record, 246, 87-97.
Kunkle, R.A. & Rimler, R.B. (1996). Pathology of acute aspergillosis in turkeys. Avian Diseases, 40, 875-886.
Lair-Fulleringer, S., Guillot, J., Desterque, C., Seguin, D., Warin, S., Chermette, R. & Bretagne, S. 2003. Differentiation
of Aspergillus fumigatus isolates from breeding turkeys and their environment by genotyping with microsatellite
markers. Journal of Clinical Microbiology, 41, 1798-1800.
Le Loc’h, G., Arné, P., Bougerol, C., Risi, E., Péricard, J.M., Quinton, J.F., Bretagne, S. & Guillot, J. (2006) Detection of
circulating serum galactomannan for the diagnosis of avian aspergillosis. 16th Congress of the International
Society for Human and Animal Mycology (ISHAM), June 25-29th 2006, Paris (Poster).
Morris, M.P. & Fletcher, O.J. (1988). Disease prevalence in Georgia turkey flocks in 1986. Avian Diseases, 32, 404-406.
Peden, W.M. & Rhoades, K.R. (1992). Pathogenicity differences of multiple isolates of Aspergillus fumigatus in
turkeys. Avian Diseases, 36, 537-542.
Redig, P.T., Post, G.S., Concannon, T.M. & Dunette, J. (1986). Development of an ELISA for the detection of
aspergillosis in avian species. Proceedings of the Association Avian Veterinarians, 165-178.
Redig, P.T. (1993). Avian aspergillosis. In: Fowler ME (Ed) Zoo and wild animals medicine. WB. Saunders Company,
Philadelphia, 178-181.
Richard, J.L. (1997). Aspergillosis. In: Diseases of poultry. Calmek B.W. (Ed), Mosby-Wolfe, London, 351-365.
Taylor, J.J. & Burroughs, E.J. (1973). Experimental avian aspergillosis. Mycopathologia Mycologia Applicata, 51, 131-
141.
Tell, L.A. (2005). Aspergillosis in mammals and birds: impact in veterinary medicine. Medical Mycology, 43, S71-S73.