Although fecal-oral transmission of avian influenza viruses (AIV) via contaminated water represents a recognized mechanism for transmission within wild waterfowl populations, little is known about viral persistence in this medium. In order to provide initial data on persistence of H5 and H7 AIVs in water, we evaluated eight wild-type low-pathogenicity H5 and H7 AIVs isolated from species representing the two major influenza reservoirs (Anseriformes and Charadriiformes). In addition, the persistence of two highly pathogenic avian influenza (HPAI) H5N1 viruses from Asia was examined to provide some insight into the potential for these viruses to be transmitted and maintained in the environments of wild bird populations. Viruses were tested at two temperatures (17 C and 28 C) and three salinity levels (0, 15, and 30 parts per thousand sea salt). The wild-type H5 and H7 AIV persistence data to date indicate the following: 1) that H5 and H7 AIVs can persist for extended periods of time in water, with a duration of infectivity comparable to AIVs of other subtypes; 2) that the persistence of H5 and H7 AIVs is inversely proportional to temperature and salinity of water; and 3) that a significant interaction exists between the effects of temperature and salinity on the persistence of AIV, with the effect of salinity more prominent at lower temperatures. Results from the two HPAI H5N1 viruses from Asia indicate that these viruses did not persist as long as the wild-type AIVs.

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This is a descriptive study designed to correlate diagnostic real-time PCR results with histopathologic lesions in cats with clinical signs of upper respiratory infection (URI).The study occurred over a 9-month period in a single open-intake animal shelter. Cats that were selected for euthanasia by the shelter staff and additionally had URI were included in the study, for a total of 22 study cats. Combined conjunctival and oropharyngeal swab specimens were tested by quantitative real-time PCR (qPCR) for feline herpesvirus type 1 (FHV-1), feline calicivirus (FCV), Mycoplasma felis, Chlamydophila felis, and Bordetella bronchiseptica. Necropsy was performed on all cats, and a complete set of respiratory tract tissues was examined by histopathology. Among 22 cats, 20 were qPCR positive for FHV-1, 7 for M. felis, 5 for FCV, 1 for C. felis, and 0 for B. bronchiseptica. Nine cats were positive for two or more pathogens. Histopathologic lesions were present in all cats, with consistent lesions in the nasal cavity, including acute necroulcerative rhinitis in 16 cats. Histologic or antigenic detection of FHV-1 was seen in 18 of 20 cats positive for FHV-1 by qPCR. No lesions that could be specifically attributed to FCV, M. felis, or C. felis were seen, although interpretation in this cohort could be confounded by coinfection with FHV-1. A significant agreement was found between the amount of FHV-1 DNA determined by qPCR and the presence of specific histopathologic lesions for FHV-1 but not for the other respiratory pathogens.Upper respiratory infection (URI) is the most frequent disease reported in the 2 million to 6 million cats estimated to pass through United States shelters each year. Feline URI results from a complex, multifactorial interaction of respiratory pathogens, stress, and animal susceptibility. Intensive housing of cats, such as that found in animal shelters, catteries, and multicat households, can contribute to disease both by compromise to the host (stress, travel, poor health status) and by exposure, dose, and, potentially, evolution of the contributing pathogens. Although mortality is low, clinical signs of URI are discerning criteria in many shelters for euthanasia, so the consequences for affected cats are profound. Moreover, chronic, recurrent rhinosinusitis, considered incurable, may be a sequela of acute rhinitis (10).Many epidemiologic and diagnostic studies have identified five pathogens commonly associated with feline URI, which are feline herpesvirus type 1 (FHV-1), feline calicivirus (FCV), Bordetella bronchiseptica, Mycoplasma felis, and Chlamydophila felis (1,5,9,15,17,21). Clinical and diagnostic investigation is complicated for a number of reasons: clinical signs of infection with any one or combination of these five pathogens are overlapping and often nonspecific. Vaccination, common for FHV-1, FCV, and C. felis, can attenuate but is not protective of disease and/or shedding (14,16,20), and lastly, all of these microbes can be carried by and detected in clinically normal cats either as lat...

Abstract.A 10-month-old, female African pygmy falcon (Polihierax semitorquatus) hatched and housed at the San Diego Zoo developed neurologic signs and died from a cerebral infection with the rat lungworm Angiostrongylus cantonensis. There was an associated mild nonsuppurative meningoencephalitis. This infection was diagnosed on histology and confirmed by detection of species-specific A. cantonensis DNA in formalin-fixed and frozen brain tissue by a polymerase chain reaction assay. To the authors' knowledge, this infection has not previously been reported in a bird in the United States and has not been known to be naturally acquired in any species in this region of the world. The source of the infection was not definitively determined but was possibly feeder geckos (Hemidactylus frenatus) imported from Southeast Asia where the parasite is endemic.