AVIAN ZOONOTIC DISEASES

Abstract

INTRODUCTION
When handling birds, whether poultry or wild birds, it is important to remember that there are several avian diseases which can also make humans sick. The term ‘zoonoses’ refers to diseases that can be passed from non-human animals to humans.
The ability of an organism to cause disease varies between different strains of that species. For example, while some strains of the flu-bug can make you very sick, there are others that have a minimal affect on your health if you are exposed to them. This is known as the “virulence” of the organism.
Although birds can spread germs to people, illness caused by touching or owning birds is rare. To best protect yourself from getting sick, thoroughly wash your hands with running water and soap after contact with birds or their droppings.
Different types of birds can carry different diseases. For example, baby chicks and ducklings often carry the bacterium Salmonella. This germ causes salmonellosis in people. Parakeets and parrots can carry the bacterium Chlamydia psittaci. This germ causes the disease psittacosis. Pigeon droppings can have germs that make people sick.

Full text

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INTRODUCTION
When handling birds, whether poultry or wild birds, it is important to remember that there are
several avian diseases which can also make humans sick. The term ‘zoonoses’ refers to diseases
that can be passed from non-human animals to humans.
The ability of an organism to cause disease varies between different strains of that species. For
example, while some strains of the flu-bug can make you very sick, there are others that have a
minimal affect on your health if you are exposed to them. This is known as the “virulence” of the
organism.
Although birds can spread germs to people, illness caused by touching or owning birds is rare. To
best protect yourself from getting sick, thoroughly wash your hands with running water and soap
after contact with birds or their droppings.
Different types of birds can carry different diseases. For example, baby chicks and ducklings
often carry the bacterium Salmonella. This germ causes salmonellosis in people. Parakeets and
parrots can carry the bacterium Chlamydia psittaci. This germ causes the disease psittacosis.
Pigeon droppings can have germs that make people sick.
ZOONOSES
‘Zoonosis’ comes from the Greek words zoon (animal) and osis (ill). The 2008 Communicable
Diseases Intelligence Report defines zoonoses this way: ‘A zoonosis is an infection or infectious
disease transmissible under natural conditions from vertebrate animals to humans. Animal hosts
play an essential role in maintaining the infection in nature, and humans are only incidental hosts.’
The term “zoonosis” is defined as “an infection or infestation shared in nature by man and lower
vertebrate animals.” Even though it is much more likely that we will acquire contagious diseases
from our fellow humans rather than from other species, many people are very concerned about
zoonotic diseases that they might “catch” due to association with the animal kingdom.
AVIAN ZOONOTIC DISEASES

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TYPES OF AVIAN ZOONOTIC DISEASES
A. Viral Zoonoses
1. Avian Influenza (AI)
2. Newcastle Disease (ND)
3. West Nile Virus
B. Bacterial
1. Chlamydiosis /Psittacosis
2. Salmonellosis
3. Avian Tuberculosis
4. Colibacillosis
5. Erysipelas
6. Pasteurellosis
C. Fungal
1. Histoplasmosis
2. Cryptococcosis
3. Aspergillosis
D. Protozoal
Sarcocystis
E. External Parasitic Zoonoses
AVIAN INFLUENZA
Organism: Highly Pathogenic H5N1 avian influenza virus
Hosts: Birds, humans and other mammals such as pigs, tigers, leopards, ferrets, stone-marten
and domestic cats.
Seasonality: Year round.
Transmission: Direct contact with infected birds, contact with surfaces contaminated with
feces, oral or nasal discharge from infected birds. Eating raw or undercooked poultry and poultry
products.
Infection in Human:
The risk from avian influenza is generally low to most people, because the viruses do not usually
infect humans. However, H5N1 is one of the few avian influenza viruses to have crossed the
species barrier to infect humans. The H1N1 virus is another.

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Confirmed cases of human infection from several subtypes of avian influenza infection, including
H5N1, have been reported since 1997. H5N1 has caused the largest number of detected cases of
severe disease and death in humans. In outbreaks in Asia and Europe, more than half of those
infected with the H5N1 virus have died.
To date, most cases of avian influenza infection in humans have resulted from close contact with
living, infected poultry (domesticated chicken, ducks, and turkeys) or surfaces contaminated with
secretion/excretions from infected birds. Dogs and cats can become infected with virus, so some
authorities have expressed concern that they might be able to pass the virus to humans, although
there are no documented cases of such transmission to date.
There is concern that the H5N1 virus will adapt over time to be able to infect and spread person-
to-person. There was person-to-person transmission of the virus within an Indonesian family in
which seven people died. Scientists found that the virus had mutated slightly, but not into a form
that could be passed on easily.
In humans, the symptoms of avian influenza range from typical flu-like symptoms (such as fever,
cough, sore throat and muscle aches), to eye infections, pneumonia, acute respiratory distress,
diarrhea, brain disease and other severe and life-threatening complications.
Disease in Birds:
Field signs: Sometimes sudden death without clinical signs.
Gross lesions: Varies, congestion and hemorrhage in multiple tissues.
Control in birds: Prevent access to infected poultry and contaminated materials.
F
ig:
Transmission of AI Virus

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Disease in Humans:
Clinical signs: Include fever, sore throat, cough, muscle aches, eye infections and
pneumonia and severe respiratory infections.
Diagnosis: Laboratory confirmation of the virus in patient samples
Treatment: Antiviral drugs and supportive care
Minimizing Risk:
In Human: Wear gloves, mask and protective clothing, disinfect well.
In Pet Birds: Keep pet birds indoors and don't allow contact with other birds, especially wild
birds.
Outdoor Birds: Here are some tips from to help reduce the risk of any type of disease
transmission via bird feeders and also predation at feeders:
 Feed only limited amounts of food on a daily basis.
 Feed only fresh, natural foods.
 Clean feeders weekly with a 10% bleach solution.
 Periodically “take a break.” Stop feeding for 5-7 days to allow birds to disperse and reduce
habitual predation by natural and introduced predators.
 If you see signs of disease at your feeder, stop feeding for a 3-4 weeks.
 Naturescape your yard to provide for the birds in a more natural manner.
 Remember that bird feeding simply supplements a natural diet. The birds will not starve if
you discontinue feeding.
NEWCASTLE DISEASE
Organism: Avian paramyxovirus-1
Hosts: Birds
Seasonality: Generally March through September- breeding season
Transmission: Direct contact with affected birds, inhalation or ingestion of contaminated
material. Can survive in the environment, especially in feces.
Disease in wild birds: More than 230 species of birds have been found to be susceptible, in
addition to poultry
Field signs: Uncoordinated movement, head twisted over back, weakness, muscle
tremors, paralysis of one or both wings and legs.
Gross lesions: Nonspecific, maybe mildly enlarged livers and spleens

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Control in birds: Coordinate with State veterinarian and Federal animal health officials to
minimize potential poultry health risks. Strict biosecurity to contain to as small an area as
possible. Possibly carcass collection and disposal.
Disease in humans: Contracted thorough contact with affected birds
Clinical signs ― Conjunctivitis and possibly mild flu like symptoms.
Diagnosis — confirmed by detecting virus in samples
Treatment ― supportive care, infections are usually self-limiting.
Minimizing Risk of Human Infections: Wear gloves, mask and coveralls, disinfect
equipment and supplies.
Prevention: The disease can be prevented by immunizing susceptible birds and obtaining birds
from flocks free of infection. Good personal-hygiene practices which include hand washing after
handling animals or their waste should be in place.
WEST NILE VIRUS
Organism: Single-stranded RNA virus of genus Flavivirus; member of the Japanese
encephalitis virus antigenic complex; arbovirus (arthropod-borne)
Hosts: Birds act as reservoir; humans, horses, most other mammals susceptible to infection but
are dead-end hosts
Seasonality: Coincides with mosquito season (varies with geographic region/climate); peak
incidence of human disease in North America occurs in late August and early September
Transmission: Transmitted by mosquito vector (Culex species)--Infectious mosquitoes carry
virus particles in their salivary glands and infect susceptible animals/humans during blood-meal
feeding.
Fig: Conjunctivitis in Human Eye

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Disease in Bird: Virus has been detected in dead birds of at least 317 species; crows and jays
especially susceptible to illness or death; most species survive infection.
Field Signs: Most birds found dead. Emaciation, trembling, difficulty in balance, inability to
fly, stand or perch, unafraid of humans, may be blind.
Gross Lesions: Inflammation of the heart and brain
Disease in Humans: Reportable disease since 1999. Primarily transmitted by mosquito bites
Clinical Signs: Incubation period 3-14 days; most infections (80%) cause no symptoms;
West Nile fever (20%): flu-like symptoms including fever, fatigue, headache, muscle or
joint pain; West Nile Meningitis, West Nile Encephalitis, West Nile Poliomyelitis (<1%)
severe neuroinvasive disease; high fever, stiff neck, disorientation, tremors, muscle
weakness, paralysis, encephalitis or meningitis; severe cases may be fatal;
Diagnosis: Detection of IgM antibody to WNV in serum or CSF (ELISA, indirect IFA,
hemagglutination inhibition tests); plaque reduction neutralization test more specific
Treatment — non-specific; supportive care including hospitalization, intravenous fluids,
respiratory support, prevention of secondary infections
Minimizing Risk of Human Infection: Occupations at risk: outdoor (farmers, foresters,
landscapers, gardeners, laborers, etc.), laboratory (diagnosticians, technicians, pathologists), field
workers (wildlife biologists, veterinarians, researchers, etc.)
Minimize exposure to mosquito bites (mosquito repellents, protective clothing), eliminate
mosquito breeding areas, protective clothing when handling animals to avoid exposure to blood
and tissues, vector control programs (insecticide spraying, draining of wetlands, etc.)
Fig:
Transmission of West Nile Virus

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BACTERIAL ZOONOSES
CHLAMYDIOSIS /PSITTACOSIS
Organism: Chlamydia psittaci, intracellular bacteria excreted in the feces and nasal discharges
of infected birds.
Hosts: Mammals (cats, sheep, goats, cattle, pigs, humans) and birds
Seasonality: Any time of year; active shedding increased by stress (shipping, crowding,
chilling, breeding); important in colonial nesting birds
Transmission: Inhalation of aerosols, inhalation or ingestion of dry fecal contaminated
materials (dust)
Disease in Birds: All birds are susceptible. Occurs worldwide in feral pigeons. Waterfowl,
herons, and pigeons are the most commonly infected wild birds in North America. Carrier birds
appear healthy but can shed the organism intermittently in feces and nasal discharges. Exposure to
nestlings is major mode of transmission.
Field Signs: Ranges from inapparent infection to a severe disease with high mortality;
lethargy, anorexia, ruffled feathers; serous or mucopurulent ocular or nasal discharge,
diarrhea, and excretion of green to yellow-green urates. Birds can die soon after onset or
become emaciated and dehydrated before death.
Gross Lesions: Most common change is enlargement of the spleen or liver; pericarditis; lung
and air sac congestion
Control in Birds: Sick birds should be collected and euthanized and carcasses should be
picked up; treatment with antibiotics; isolation/quarantine
Disease in Humans: Occurs when a person inhales the organism, which has been aerosolized
from respiratory secretions or dried feces of infected birds; other means of exposure include bird
bites, mouth-to-beak contact, and the handling of infected birds’ plumage and tissues.
Fig:
Transmission
o
f Psittacosis

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Clinical Signs: Incubation period of 5 to 14 days; severity varies from inapparent illness to
systemic illness with severe pneumonia; flu-like symptoms; nonproductive cough; pneumonia
Diagnosis: Can be difficult (antibiotic treatment may prevent an antibody response);
laboratory confirmation (culture, antibody titer)
Minimizing Risk of Human Infection: Use respirator to avoid inhaling airborne avian fecal
material when cleaning cages or handling infected birds; mask may not be effective. Wet down
dry, dusty areas with bird droppings with disinfectant. Avoid working with large numbers of birds
in dusty, closely confined areas. Wear protective clothing, gloves, cap. Wet down carcasses and
use hood for necropsies.
SALMONELLOSIS
Organism: Bacteria of genus Salmonella — S. typhimurium is the most common in wild birds
in the US
Hosts: Birds, mammals, reptiles; bacteria live in the intestinal tracts
Seasonality: Any time of year
Transmission: Direct contact, contaminated food or water
Disease in Birds: All species are susceptible. Occurs worldwide. Large-scale mortalities in
passerines/songbirds using feeding stations. Young birds especially vulnerable.
Field Signs: No distinctive signs; ruffled feathers, droopiness, diarrhea, severe lethargy,
incoordination, convulsions. Rapid death of songbirds mimics poisoning.
Gross Lesions: Swollen and crumbly livers with small reddened or pale spots in prolonged
infections; reddening of the internal lining of the posterior small intestine. Yellow, cheesy
nodules on the surface of the esophagus of songbirds.
Control in Birds: Eliminate points of infection: garbage, sewage wastewater, wastewater
discharges from livestock and poultry operations. Eliminate contamination of migratory bird
habitat from intentionally using wastewater to create wetland habitat. Public education to
maintain clean feeding stations. Strict sanitation and testing in captive flocks during and
before release into the wild.

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Disease in Humans: Most common source is eating foods contaminated with animal feces
(beef, poultry, milk, eggs and vegetables); inadequate hand washing after handling infected
animal or contact with feces
Clinical Signs: Most people infected with salmonellosis develop diarrhea, fever, and
abdominal cramps 12 to 72 hours after infection. Illness usually lasts 4 to 7 days.
Diagnosis: Laboratory tests to identify Salmonella in the stools of an infected person
Treatment: Most people recover without treatment. The elderly, infants, and
immunocompromised people are more likely to have a severe illness and require treatment
with antibiotics.
Minimizing Risk of Human Infection: Extra care with personal hygiene is warranted by
people who handle birds or materials soiled by bird feces.
Protection of Human from Salmonella Infection:
 Wash your hands thoroughly with soap and water right after touching animals, their food
(e.g., dry dog or cat food, frozen feeder rodents, etc.) or treats (e.g., rawhide bones, pig
ears, biscuits, etc.) or anything in the area where they live and roam.
 Running water and soap are best. Use hand sanitizers if running water and soap are not
available. Be sure to wash your hands with soap and water as soon as a sink is available.
Directions for washing hands can be found here. Adults should always supervise hand
washing for young children.
 Do not let children younger than 5 years of age, older individuals, or people with
weakened immune systems handle or touch high-risk animals (e.g., turtles, water frogs,
chicks, ducklings), or anything in the area where they live and roam, including water from
containers or aquariums.
Fig:
Eating Raw Egg Causes Salmonellosis

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 Keep live poultry, amphibians, and reptiles out of homes and facilities with children
younger than 5 years old or people with weakened immune systems.
 Don't eat or drink around high-risk animals (e.g., turtles, water frogs, chicks, ducklings),
or in areas where they live and roam. Keep animals away from areas where food and drink
are prepared, served, or stored, such as kitchens or outdoor patios.
 Use soap or a disinfectant to thoroughly clean any surfaces that have been in contact with
animals. Children older than 5 years of age should perform this task only under adult
supervision.
 Habitats and their contents, such as food and water bowls, should be carefully cleaned
outdoors, if possible. If bathtubs must be used for these purposes, they should be
thoroughly cleaned and disinfected with a bleach solution afterward.
 High risk individuals should avoid cleaning habitats and their contents, but if unavoidable,
they should use disposable gloves when cleaning and do not dispose of water in sinks used
for food preparation or for obtaining drinking water.
AVIAN TUBERCULOSIS
Organisms: Avian tuberculosis is usually caused by the bacterium Mycobacterium avium. At
least 20 different types of M. avium have been identified, only three of which are known to cause
disease in birds. Other types of Mycobacterium rarely cause tuberculosis in most avian species.
Host: All avian species are susceptible to infection by M. avium. Humans, most livestock
species, and other mammals can also become infected.
Distribution: Avian tuberculosis is a ubiquitous and cosmopolitan disease of free-ranging,
captive, and domestic birds. The disease is most commonly found in the North Temperate Zone,
and, within the United States, the highest infection rates in poultry are in the North Central States.
Seasonality: The chronic nature of this disease guarantees its presence year-round for both wild
and captive birds.
Transmission: Inhalation of aerosols; fecal-oral route; handling contaminated objects; contact
with contaminated surfaces. The bacteria are transmitted from infected birds primarily via the
aerosol route, so exposure can occur through dirty bedding, as well as from birds coughing and
sneezing. Avian TB is common and often found in birds purchased from feed stores. TB may
affect virtually every organ system but infected birds may show no obvious symptoms. In man,
any organ system may be affected, although the most familiar signs are related to lesions in the
lungs.

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Clinical Signs:
Animals: Symptoms of Avian Tuberculosis include a swollen abdomen, weight loss,
diarrhea, impaired breathing, and increase volume of the white urates in a bird's droppings.
Humans: Asymptomatic to night sweats, weight loss, abdominal pain, fatigue, diarrhea,
& cough in people with immunosuppression or preexisting lung damage.
Diagnosis: Diagnosis of tuberculosis in the live bird can be very difficult due to intermittent
fecal shedding and obscure signs. Physical findings, very elevated white blood cell and low red
blood cell count and other diagnostic tests which include radiology (x-rays), endoscopy and
identification of acid fast bacteria in feces or tissues can lead to a preliminary diagnosis.
Definitive diagnosis is based on culturing the organism from the feces or from an organ. Not all
acid fast organisms are mycobacteria, therefore just identifying acid fast organisms does not
provide a conclusive diagnosis. New tests that may aid in the diagnosis include the DNA probe
and the polymerase chain test.
To Prevent Disease Transmission:
In Bird: Poultry from clean flocks should be used if possible,
In Man: Wear protective masks when exposed to dust or using spray hoses to wash
poultry cages.
Erradication:
 Erradication is difficult due to the chronic carrier state and intermittent shedding of a large
number of organisms.
 If a positive bird is identified, it should be separated from the collection. Treatment of a
positive bird is contaversial because of the large number of organisms shed in the feces
and because the organism is resistant to many of the drugs used to treat human T.B. The
infected bird must be treated for a long period using combination drug treatment.
 All contact birds should be quarantined for 2 years and tested at 6-12 week intervals.
 People who are infected with human tuberculosis should not own birds, since these people
may serve as a source of infection for their pet birds.
Fig:
The raised, firm nodules in Intestine
of Bird

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COLIBACILLOSIS
Organism: Escherichia coli Gram-negative rod; serotypes 01, 02, or 078, but often untypeable
Host: All avian species are susceptible to infection by E. coli including man.
Transmission:
In Bird: The bacteria are shed from an infected bird in the fecal material as well as nasal and or
ocular secretions. The organism remains stable outside the host body and may dry as a dusty
substance. This dust contaminates the air in the form of aerosols. These aerosols are then inhaled
by another possible host
In Man: Eating poorly butchered and undercooked meat.
Clinical Sign:
In Bird: Signs of colibacillosis are respiratory distress, reduced appetite and poor growth. Lesions
seen at post mortem are airsacculitis, pericarditis, perihepatitis and peritonitis. Figures 1, 2 and 3
illustrate the clear airsac of an uninfected bird, the foamy exudate seen early in infection, and the
caseous exudate later in infection.
In Man: Certain strains of E. coli, such as O157:H7, O104:H4, O121, O26, O103, O111, O145,
and O104:H21, produce potentially lethal toxins. In man, the bacteria can cause profuse and
watery diarrhea, abdominal colic and vomiting. The major mode of transmission is fecal/oral
route. Prevention is by wearing protective clothing when handling birds, eggs or body tissues.
Diagnosis: Histopathology; bacterial culture of affected organs is required for diagnosis.
Treatment: E. coli isolates from commercial poultry are often resistant to a variety of
antibiotics. This is compounded by the fact that few antibiotics are being put on the market for
poultry. Enrofloxacin was effective against this organism, but the antibiotic was removed from
food production use in 2006. Regardless, culture and sensitivity may assist treatment if more
than one bird is affected.
Prevention: Vigorous sanitation program in breeder house, at hatchery and at grow-out facility;
Egg fumigation; dust control in house; routinely remove dead birds from house, avoid stress and
immunosuppression (IBD).

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ERYSIPELAS
Organism: Erysipelothrix rhusiopathiae is a Gram-positive, catalase-negative, rod-shaped
bacterium. It grows aerobically and anaerobically and does not contain endotoxin.
Found largely in turkeys, ducks and budgies with eye disease, but is not limited to that list. It can
be contracted from the flesh of dead animals or contaminated soil around dead animals.
Diseases in Man: In humans it appears as a generalised illness, with skin lesions and joint
disease. E. rhusiopathiae infections most commonly present in a mild cutaneous form known as
erysipeloid. Less commonly, it can result in sepsis; this scenario is often associated with
endocarditis.
PASTEURELLOSIS
Organism: Pasteurella multocida is a Gram-negative, nonmotile, penicillin-sensitive
coccobacillus belonging to the Pasteurellaceae family.
Transmission:
In Bird: All animals and birds may be colonized by this bacterium, especially throughout the
respiratory tract and mouth.
In Man: P multocida infection in humans is often associated with an animal bite, scratch, or lick,
but infection without epidemiologic evidence of animal contact may occur.
Diseases in Bird: causes Fowl Cholera that is a serious, highly contagious disease caused by
the bacterium Pasteurella multocida in a range of avian species including chickens, turkeys, and
water fowl, (increasing order of susceptibility). It is seen worldwide and was one of the first
infectious diseases to be recognised, by Louis Pasteur in 1880.
Diseases in Man: Human infection occurs through wounds made by bites or scratches and
may cause acute pneumonia or septicemic disease.
Fig: Pasteurella multocida in man
andbird

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FUNGAL ZOONOSES
HISTOPLASMOSIS
Organism: Fungus Histoplasma capsulatum
Hosts: Grows in soil and material contaminated with bird or bat droppings; found in poultry
house litter, caves, areas harboring bats, bird roosts (particularly starlings, grackles, red-winged
blackbirds, and cowbirds)
Geographic Regions and Habitats: Found worldwide; endemic in certain areas of the US
(particularly states bordering the Ohio River valley and the lower Mississippi River-- KY, IL, IN,
MO, OH, TN)
Disease in Birds: Birds do not appear to be infected by H. capsulatum; bird droppings are
primarily a nutrient source for the growth of the organism already in the soil; organism can be
carried on the wings, feet, and beaks of birds and contaminate soil under roosting sites or manure
accumulations inside or outside buildings
Disease in Humans: Primarily affects the lungs. Transmission by inhalation of spores when
contaminated soil/material is disturbed. High risk jobs—chimney cleaner, bridge worker,
construction/demolition workers, farmer/gardener, lab worker, spelunker
Clinical Signs: Symptoms appear 3-17 days after exposure. Most infected people are
asymptomatic or have only mild flu-like symptoms. Infants, young children, and older
persons, in particular those with chronic lung disease are at increased risk for severe
disease.
Acute pulmonary disease: Respiratory symptoms, malaise, fever, chest pains, dry or
nonproductive cough;
Fig: Transmission of Histoplasma spores

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Chronic pulmonary disease: Resembles TB; Disseminated form (more frequently seen in
people with cancer, AIDS, or other forms of immunosuppression)—most severe and rare
form; affects multiple organ systems and is fatal unless treated
Diagnosis: Distinct patterns may be seen on chest x-ray; identification of organism in samples
of sputum, blood, or infected organs; detection of antigens in blood or urine samples by
ELISA or PCR; antibody test in blood
Treatment: Mild cases usually resolve without treatment; antifungal medications used to treat
severe cases of acute disease and all cases of chronic and disseminated disease.
Minimizing Risk of Human Infections:
 Best to assume soil in endemic regions and any accumulations of bat droppings or bird
manure are contaminated—testing of soil samples is expensive, time consuming, not
foolproof; PCR method being developed.
 Avoid areas that may harbor the fungus (accumulations of bird or bat droppings). Use
proper PPE, NIOSH-approved respirator. Suppress dust by wetting.
CRYPTOCOCCOSIS
Organism: Cryptococcosis is a fungal disease caused by Cryptococcus neoformans or
Cryptococcus gattii.
Transmission: Cryptococcus neoformans, the fungus that causes this disease, is ordinarily
found in soil. It enters and infects the body through the lungs. Once inhaled, infection with
cryptococcosis may go away on its own, remain in the lungs only, or spread throughout the body
(disseminate).
Diseases in Bird: C. neoformans can be found in the guano of asymptomatic birds. This
organism is especially prevalent in droppings from columbiform birds (e.g., pigeons), but it has
also been detected occasionally in fecal matter or cloacal swabs from some psittacine and
passerine species, chickens, swans (Cygnus spp.), rheas (Rhea spp.) and raptors. C. neoformans is
able to temporarily colonize the intestinal tract of some avian species. Clinical cases are
uncommon in birds, although psittacines are occasionally affected by C. neoformans var. grubii or
C. gattii. Several cases of cryptococcosis, all caused by C. gattii, were described in captive North

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Island brown kiwis (Apteryx australis mantelli). Cryptococcosis seems to be very rare in poultry
and pigeons, although the latter species can be exposed to massive quantities of C. neoformans.
Diseases in Man: Symptoms of Cryptosporidiosis in birds include gastrointestinal problems
such as diarrhea, lethargy, weight loss, and respiratory problems.
ASPERGILLOSIS
Organism: A fungal infectious disease, caused by Aspergillus fumigates.
Diseases in Man: A fungus ball in the lungs may cause no symptoms and may be discovered
only with a chest X-ray, or it may cause repeated coughing up of blood and occasionally severe,
even fatal, bleeding. A rapidly invasive Aspergillus infection in the lungs often causes cough,
fever, chest pain, and difficulty breathing.
Diseases in Bird:
 Yellow to grey nodules or plaques in lungs, air sacs, trachea, plaques in peritoneal cavity,
may have greenish surface.
 Conjunctivitis/keratitis.
 Brain lesions may be seen in some birds with nervous signs.
Fig:
Cryptococcus skin lesions.
Fig
:
Aspergillus
affected lung of chicken and man

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Diagnosis: This is usually based on the signs and lesions and microscopic examination for the
fungus, preferably after digestion in 10% potassium hydroxide. It may be confirmed by isolation
of the fungus, typically by putting small pieces of affected tissue on Sabouraud agar. Growth
occurs in 24-48 hours and colonies are powdery green/blue in appearance. Differentiate from
excessive exposure to formalin or vaccinal reactions in day olds and from heat stress in older
birds.
Treatment: Usually none. Environmental spraying with effective antifungal antiseptic may help
reduce challenge. Amphotericin B and Nystatin have been used in high-value birds.
Prevention: Dry, good quality litter and feed, hygiene, Thiabendazole or Nystatin has been
used in feed.
PROTOZOALZOONOSES
SARCOCYSTIS
Organism: Sarcocystis is a genus of protozoa. Species in this genus are parasites, the majority
infecting mammals, and some infecting reptiles and birds.
Sarcocystis falcatula is the species associated with an acute fatal disease in psittacine birds.
Disease occurs during the early stages of the infection as the parasite is undergoing schizogony
(an asexual reproductive stage) in the lung.

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Sign in Bird: Symptoms of Sarcocystis include lethargy, shortness of breath, tail bobbing,
yellow tinted droppings, and sudden death.
Sign in Man:
Intestinal Sarcocystosis: Signs that appeared 3 to 6 h after eating the beef included nausea,
stomach ache, and diarrhea; these were transient and lasted about 36 h. In a second series
symptoms - abdominal pain, distension, watery diarrhea and eosinophilia - appeared at 1 week
and resolved after 3 weeks.
Muscular Sarcocystosis: Painful swellings about 1 to 2 cm in diameter on extremities ,
subcutaneous masses associated with overlying erythema and subsided spontaneously about 2
weeks later.
EXTERNAL PARASITIC ZOONOSES
External Parasites of poultry will not readily live on the skin and in the hair of man. Therefore,
they are not considered to have "zoonotic" potential. Nevertheless, any bird noted to be infected
with mites or lice should be immediately treated. Notify the facility supervisor and/or veterinarian
if you suspect a problem with external parasites! Heavy infestations of mites and lice are often
seen in the spring and summer. To eliminate external parasites, all birds housed in a particular
room or building must be treated at the same time and there must be repeated treatment of the
birds, as well as cleaning and treatment of the housing area.
Lice are the most common external parasites of birds. There are many different species and most
are biting insects that consume scales, feathers, bits of skin and feces.
Scaly-Leg Mites infest the featherless areas of the face and legs, burrowing into the skin and
feather follicles, feeding on connective tissue.
Quill Mites infest and destroy new feathers. The mites burrow into the feather shaft and as a
result of their activity produce a powdery mass of feather debris, eggs, larvae, molted mite skins
and feces visible through the shaft wall.
Fig: Scaly-leg mite Chicken head louse Quill mite

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