All birds are considered susceptible to poxvirus infection, but many companion and aviary birds are rarely exposed to a susceptible strain. In pet bird practice, veterinarians will generally encounter only canary and , pigeon poxviruses, and fowlpox Fowlpox read more , which have specific host ranges.
Poxviruses are environmentally stable, increasing the likelihood that a viable organism will come into contact with a susceptible host. Poxviruses cannot penetrate intact skin, and a break in the skin or mucous membrane must be present for infection to occur. Poxvirus infection may cause cutaneous, diphtheritic, or systemic infections based on the strain of virus, route of exposure, affected species, and age and health of the bird.
The cutaneous form appears as nodular proliferations or wartlike lesions on the unfeathered skin around the eyes, beak, nares, and legs. The diphtheritic form is characterized by lesions on the mucosa, tongue, pharynx, and larynx.
The septicemic form is characterized by a ruffled appearance, depression, cyanosis, anorexia, and wartlike tumors of the skin. The cutaneous form is most commonly seen in psittacines and raptors. Clinical signs depend on the form of disease, location of the lesions eye, oral, ear , and overall health of the bird and may include lethargy, respiratory distress, partial blindness, difficulty eating, weight loss, emaciation, and skin lesions.
Diagnosis of poxvirus infection is typically confirmed through history, physical examination findings, and histologic findings of Bollinger bodies in affected tissues. Treatment is usually nonspecific and may include supportive care, fluids, parenteral vitamin A, ophthalmic ointments for eye infections, assisted feedings, and antimicrobials to prevent or treat secondary infections.
Lesions on the skin may need daily cleaning. Transmission is via insect vectors mosquito bites or other entry through breaks in the skin. Therefore, mosquito control and indoor housing are vital to prevent outbreaks. Vaccines for canarypox, fowlpox, and pigeonpox are available but are specific for their host species. Viscerotropic velogenic Newcastle disease Newcastle Disease and Other Paramyxovirus Infections read more VVND , caused by a paramyxovirus group 1, affects most avian species and is an important threat to the poultry industry.
It is rare in captive-bred parrots housed indoors. Transmission is by respiratory aerosols, fecal contamination of food or water, direct contact with infected birds, and fomites. Birds may be asymptomatic or die acutely. Clinical signs include depression, anorexia, weight loss, sneezing, nasal discharge, dyspnea, conjunctivitis, bright yellow-green diarrhea, ataxia, head bobbing, and opisthotonos.
In prolonged cases, unilateral or bilateral wing and leg paralysis, chorea, torticollis, and dilated pupils also may be seen. Primary differential diagnoses include other paramyxoviruses Other Paramyxovirus Infections Avian polyomavirus APV causes disease in young parrots.
In pet birds, toxicosis often occurs from ingestion of metal in the home Lesions include hepatomegaly, splenomegaly, petechial or ecchymotic hemorrhages on serosal surfaces of all viscera and air sacs, airsacculitis, and excess straw-colored peritoneal fluid. Diagnosis is traditionally via viral isolation, but agar gel immunodiffusion tests that can be performed on whole blood or serum are available.
Only symptomatic treatment is possible and thus not advised. If suspected, VVND must be reported to appropriate federal and state authorities. There are several less pathogenic strains of paramyxovirus. Paramyxovirus groups 2 and 3 are endemic in aviculture. Paramyxovirus group 2 causes mild illness in passerines and a more serious disease in psittacines.
Clinical signs in psittacines include tracheitis, pneumonia, and enteritis. Paramyxovirus group 3 is reported most frequently in Neophema spp, lovebirds, and gouldian finches and typically causes mild disease. Clinical signs may be absent, and disease results in acute death. In disease of longer duration, respiratory signs, pancreatitis, and torticollis may occur. Diagnosis is the same as for paramyxovirus group 1. Treatment for paramyxovirus groups 2 and 3 infections is supportive care.
The vaccine for paramyxovirus group 1 should not be used in psittacines, because it can cause fatal reactions. The American crow Corvus brachyrunchus and other corvids have suffered particularly high morbidity and mortality. Other affected species include canaries, psittacines, and raptors.
Although psittacines appear to be somewhat resistant, the disease has been reported in parakeets, cockatoos, conures, rosellas, caiques, lorikeets, and a King parrot. Affected parrots have been adults housed outdoors with documentation of mosquito populations present.
Mosquitoes Culex spp are the principal vectors of disease. Clinical signs include depression, anorexia, weight loss, head tremors, ataxia, blindness, seizures, and death.
Juvenile birds are the most commonly affected. Ophthalmologic findings in raptors are anterior uveitis, exudative chorioretinal lesions, and chorioretinal scarring. Antemortem diagnosis can be difficult. Initial diagnosis may be based on clinical signs, species, and age; however, many diseases may cause similar clinical signs.
Serologic tests serum neutralization may indicate antibody response to infection. Paired samples submitted 2 weeks apart may reveal a rise in antibody levels and give a more definitive diagnosis. Adult birds may have high circulating antibody levels in endemic areas.
PCR assay is available. Diagnosis is often determined at necropsy. The brain and kidney are the preferred tissues to submit for histopathologic examination. There is no specific treatment for WNV in birds. A vaccination protocol using a recombinant vaccine has been successful in some birds.
The recommendation is vaccination of captive birds 2—4 weeks before mosquito season, with a booster 3 weeks after the initial dose. For control , during the mosquito season, birds should be housed indoors or in completely covered outdoor facilities. Mosquito netting and mosquito traps should be used, and any standing or stagnant water sources eliminated. Avian influenza Avian Influenza read more is caused by an orthomyxovirus.
Because of the zoonotic potential of some strains and the recent discovery of new mutations, this virus may become a more important pathogen. Both the zoonotic potential and the economic effects on the poultry industry are causes for concern.
Also see pet health content regarding disorders and diseases of pet birds Introduction to Disorders and Diseases of Pet Birds Many of the most common causes of illness or death in birds are due to poor husbandry practices that result in nutritional deficiencies, trauma or poisoning due to household hazards, and unsanitary From developing new therapies that treat and prevent disease to helping people in need, we are committed to improving health and well-being around the world.
The Merck Veterinary Manual was first published in as a service to the community. This site complies with the HONcode standard for trustworthy health information: verify here. Common Veterinary Topics. Videos Figures Images Quizzes. Avian Polyomavirus.
Clinical Findings Diagnosis Treatment and Control. Psittacine Beak and Feather Disease. Clinical Findings Diagnosis Treatment and Prevention. Poxvirus Infections. Viscerotropic Velogenic Newcastle Disease. Other Paramyxovirus Infections. West Nile Virus. Avian Influenza. For More Information. Pet Birds. Test your knowledge. Though not proven, adult birds are thought to form some immunity to polyomavirus.
From the time the bird contracts the infection, it takes about days for the it to display symptoms. However, a bird may or may not show any sign of the polyomavirus infection. If the symptoms are displayed in your bird, its death may be imminent -- usually within one or two days. Since the infection lowers the immunity of the bird, it can be susceptible to other viruses, bacteria, fungi and parasites, which can lead to secondary infection and death. The polyomavirus is usually contracted through direct contact with other infected birds.
It is also contracted from infected feces, dander, air, nest boxes, incubators, feather dust or from an infected parent passing it to chick. Following strict hygiene methods, such as disinfecting nest boxes, cages, incubators or utensils, can help ensure your bird does not get infected with the polyomavirus.
The virus, however, is resistant to most disinfectants; use oxidizers like chlorine beach instead. Aviaries and pet stores should also regularly screen for the virus.
And new birds should be quarantined to ensure they do not carry the disease. Vaccination is available, but its effectiveness has still not be proven. Immunogenicity was evaluated by testing for virus-neutralizing antibodies, vaccinating each bird twice, and then testing for a significant change in antibody titer.
Efficacy was evaluated by vaccinating birds, followed in 2 to 4 weeks by intramuscular or intravenous challenge exposure. After challenge exposure, protection was evaluated by attempting to recover virus from tissues or by observing birds for clinical signs of disease and testing for a significant change in titer. Conclusions: Avian polyomavirus vaccine is safe, immunogenic, and efficacious for use in multiple species of mature and immature psittacines.
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