Pasteurellosis is an infection with a species of the bacterial genus Pasteurella, which is found in humans and other animals.
Avian influenza, also known as avian flu or bird flu, is a disease caused by the influenza A virus, which primarily affects birds but can sometimes affect mammals including humans. Wild aquatic birds are the primary host of the influenza A virus, which is enzootic in many bird populations.
Virulent Newcastle disease (VND), formerly exotic Newcastle disease, is a contagious viral avian disease affecting many domestic and wild bird species; it is transmissible to humans. Though it can infect humans, most cases are non-symptomatic; rarely it can cause a mild fever and influenza-like symptoms and/or conjunctivitis in humans. Its effects are most notable in domestic poultry due to their high susceptibility and the potential for severe impacts of an epizootic on the poultry industries. It is endemic to many countries. No treatment for VND is known, but the use of prophylactic vaccines and sanitary measures reduces the likelihood of outbreaks.
Influenza A virus subtype H5N1 (A/H5N1) is a subtype of the influenza A virus, which causes influenza (flu), predominantly in birds. It is enzootic in many bird populations, and also panzootic. A/H5N1 virus can also infect mammals that have been exposed to infected birds; in these cases, symptoms are frequently severe or fatal.
Infectious bursal disease (IBD), also known as Gumboro disease, infectious bursitis, and infectious avian nephrosis, is a highly contagious disease of young chickens and turkeys caused by infectious bursal disease virus (IBDV), characterized by immunosuppression and mortality generally at 3 to 6 weeks of age. The disease was first discovered in Gumboro, Delaware in 1962. It is economically important to the poultry industry worldwide due to increased susceptibility to other diseases and negative interference with effective vaccination. In recent years, very virulent strains of IBDV (vvIBDV), causing severe mortality in chicken, have emerged in Europe, Latin America, South-East Asia, Africa, and the Middle East. Infection is via the oro-fecal route, with affected birds excreting high levels of the virus for approximately 2 weeks after infection. The disease is easily spread from infected chickens to healthy chickens through food, water, and physical contact.
Avian infectious bronchitis (IB) is an acute and highly contagious respiratory disease of chickens. The disease is caused by avian infectious bronchitis virus (IBV), a coronavirus, and characterized by respiratory signs including gasping, coughing, sneezing, tracheal rales, and nasal discharge. In young chickens, severe respiratory distress may occur. In layers, respiratory distress, nephritis, decrease in egg production, and loss of internal and external egg quality are reported.
Marek's disease is a highly contagious viral neoplastic disease in chickens. It is named after József Marek, a Hungarian veterinarian who described it in 1907. Marek's disease is caused by an alphaherpesvirus known as "Marek's disease virus" (MDV) or Gallid alphaherpesvirus 2 (GaHV-2). The disease is characterized by the presence of T cell lymphoma as well as infiltration of nerves and organs by lymphocytes. Viruses related to MDV appear to be benign and can be used as vaccine strains to prevent Marek's disease. For example, the related herpesvirus found in turkeys (HVT), causes no apparent disease in the birds, and continues to be used as a vaccine strain for prevention of Marek's disease.
Pasteurella is a genus of Gram-negative, facultatively anaerobic bacteria. Pasteurella species are nonmotile and pleomorphic, and often exhibit bipolar staining. Most species are catalase- and oxidase-positive. The genus is named after the French chemist and microbiologist, Louis Pasteur, who first identified the bacteria now known as Pasteurella multocida as the agent of chicken cholera.
Singapore has taken a series of measures against avian influenza and the potential threat of a pandemic.
Transmission and infection of H5N1 from infected avian sources to humans has been a concern since the first documented case of human infection in 1997, due to the global spread of H5N1 that constitutes a pandemic threat.
H5 N2 is a subtype of the species Influenzavirus A. The subtype infects a wide variety of birds, including chickens, ducks, turkeys, falcons, and ostriches. Affected birds usually do not appear ill, and the disease is often mild as avian influenza viral subtypes go. Some variants of the subtype are much more pathogenic than others, and outbreaks of "high-path" H5N2 result in the culling of thousands of birds in poultry farms from time to time. It appears that people who work with birds can be infected by the virus, but suffer hardly any noticeable health effects. Even people exposed to the highly pathogenic H5N2 variety that killed ostrich chicks in South Africa only seem to have developed conjunctivitis, or a perhaps a mild respiratory illness. There is no evidence of human-to-human spread of H5N2. On November 12, 2005 it was reported that a falcon was found to have H5N2. On June 5, 2024, the first confirmed human case of H5N2 was reported in Mexico.
Duck plague is a worldwide disease caused by Anatid alphaherpesvirus 1 (AnHV-1) of the family Herpesviridae that causes acute disease with high mortality rates in flocks of ducks, geese, and swans. It is spread both vertically and horizontally—through contaminated water and direct contact. Migratory waterfowl are a major factor in the spread of this disease as they are often asymptomatic carriers of disease. The incubation period is three to seven days. Birds as young as one week old can be infected. DEV is not zoonotic.
Fowlpox is the worldwide disease of poultry caused by viruses of the family Poxviridae and the genus Avipoxvirus. The viruses causing fowlpox are distinct from one another but antigenically similar, possible hosts including chickens, turkeys, quail, canaries, pigeons, and many other species of birds. There are two forms of the disease. The first is spread by biting insects and wound contamination, and causes lesions on the comb, wattles, and beak. Birds affected by this form usually recover within a few weeks. The second is contracted by inhalation or ingestion of the virus via dust or aerosols, leading to the 'diphtheritic form' of the disease, in which diphtheritic membranes form in the mouth, pharynx, larynx, and sometimes the trachea. The prognosis for this form is poor.
The global spread of H5N1 in birds is considered a significant pandemic threat.
Pasteurella multocida is a Gram-negative, nonmotile, penicillin-sensitive coccobacillus of the family Pasteurellaceae. Strains of the species are currently classified into five serogroups based on capsular composition and 16 somatic serovars (1–16). P. multocida is the cause of a range of diseases in mammals and birds, including fowl cholera in poultry, atrophic rhinitis in pigs, and bovine hemorrhagic septicemia in cattle and buffalo. It can also cause a zoonotic infection in humans, which typically is a result of bites or scratches from domestic pets. Many mammals and birds harbor it as part of their normal respiratory microbiota.
A water bird, alternatively waterbird or aquatic bird, is a bird that lives on or around water. In some definitions, the term water bird is especially applied to birds in freshwater ecosystems, although others make no distinction from seabirds that inhabit marine environments. Some water birds are more terrestrial while others are more aquatic, and their adaptations will vary depending on their environment. These adaptations include webbed feet, beaks, and legs adapted to feed in the water, and the ability to dive from the surface or the air to catch prey in water.
Histomoniasis is a commercially significant disease of poultry, particularly of chickens and turkeys, due to parasitic infection of a protozoan, Histomonas meleagridis. The protozoan is transmitted to the bird by the nematode parasite Heterakis gallinarum. H. meleagridis resides within the eggs of H. gallinarum, so birds ingest the parasites along with contaminated soil or food. Earthworms can also act as a paratenic host.
Haemorrhagic septicaemia (HS) is one of the most economically important pasteurelloses. Haemorrhagic septicaemia in cattle and buffaloes was previously known to be associated with one of two serotypes of P. multocida: Asian B:2 and African E:2 according to the Carter-Heddleston system, or 6:B and 6:E using the Namioka-Carter system.
Egg drop syndrome '76 is a viral disease that affects birds, notably chickens, ducks, geese and swans. It is characterised by a sudden drop in production of eggs as well as its eggshell quality in apparent healthy laying birds.
Jessie Isabelle Price was a veterinary microbiologist. She isolated and reproduced the cause of the most common life-threatening disease in duck farming in the 1950s and developed vaccines for this and other avian diseases. A graduate of Cornell University, where she gained a PhD (1959), she worked first at the Cornell Duck Research Laboratory and later at the USGS National Wildlife Health Center. She served as chair of the Predoctoral Minority Fellowship Ad Hoc Review Committee of the American Society for Microbiology (ASM), and as president of Graduate Women in Science.
