Adverse events diagnosed within three days of vaccine administration in dogs

OBJECTIVE: To determine incidence rates and potential risk factors for vaccine-associated adverse events (VAAEs) diagnosed within 3 days of administration in dogs. DESIGN: Retrospective cohort study. ANIMALS: 1,226,159 dogs vaccinated at 360 veterinary hospitals. PROCEDURE: Electronic records from January 1, 2002, through December 31, 2003, were searched for possible VAAEs (nonspecific vaccine reaction, allergic reaction, urticaria, or anaphylaxis) diagnosed within 3 days of vaccine administration. Information included age, weight, sex, neuter status, and breed. Specific clinical signs and treatments were reviewed in a random sample of 400 affected dogs. The association between potential risk factors and a VAAE was estimated by use of multivariate logistic regression. RESULTS: 4,678 adverse events (38.2/10,000 dogs vaccinated) were associated with administration of 3,439,576 doses of vaccine to 1,226,159 dogs. The VAAE rate decreased significantly as body weight increased. Risk was 27% to 38% greater for neutered versus sexually intact dogs and 35% to 64% greater for dogs approximately 1 to 3 years old versus 2 to 9 months old. The risk of a VAAE significantly increased as the number of vaccine doses administered per office visit increased; each additional vaccine significantly increased risk of an adverse event by 27% in dogs < or = 10 kg (22 lb) and 12% in dogs > 10 kg. CONCLUSIONS AND CLINICAL RELEVANCE: Young adult small-breed neutered dogs that received multiple vaccines per office visit were at greatest risk of a VAAE within 72 hours after vaccination. These factors should be considered in risk assessment and risk communication with clients regarding vaccination.     

Investigation and control of an outbreak of salmonellosis caused by multidrug-resistant Salmonella typhimurium in a population of hospitalized horses

An outbreak of salmonellosis in a population of hospitalized horses resulted in the closure of a teaching hospital for a period of 10 weeks. Fecal samples were collected from suspected cases and cultured for Salmonella. Salmonella isolates were characterized using antimicrobial susceptibility testing, pulsed-field gel electrophoresis (PFGE) and phage typing. Thirty-three cases of infection by a multidrug-resistant strain of S. typhimurium were detected. The index case was admitted on 26 August 1999. Fifteen (45%) cases occurred between April and June 2000. PFGE results suggested that this strain of S. typhimurium might have been introduced into the hospital environment by a foal presenting with diarrhea. The hospital was closed on June 13, and intensive environmental cleaning and disinfection were completed. Enforcement of infectious disease control protocols in hospitals and environmental and patient surveillance is needed to prevent outbreaks of salmonellosis.     

Diagnostic comparison of needle and wedge biopsy specimens of the liver in dogs and cats

OBJECTIVE: To compare morphologic diagnoses determined from needle biopsy specimens obtained from the livers of dogs and cats with morphologic diagnoses determined from wedge biopsy specimens. DESIGN: Prospective study. ANIMALS: 124 dogs and cats. PROCEDURE: 2 needle biopsy specimens were obtained from each animal; wedge biopsy specimens were obtained from the same liver lobe during laparotomy or postmortem examination. Histologic features were scored independently by 3 individuals; a morphologic diagnosis was rendered after histologic features were scored. Cases were included only if at least 2 of the 3 examiners agreed on the morphologic diagnosis; the definitive diagnosis was considered to be the morphologic diagnosis rendered for the wedge biopsy specimen. Physical characteristics (length, width, surface area, degree of fragmentation, and number of portal triads for needle biopsy specimens and surface area for wedge biopsy specimens) were determined. RESULTS: Definitive diagnoses included hepatic necrosis (n = 10), cholangitis-cholangiohepatitis (13), chronic hepatitis-cirrhosis (12), canine vacuolar hepatopathy (11), portosystemic vascular anomaly-microvascular dysplasia (17), neoplasia (10), miscellaneous hepatic disorders (18), and no hepatic disease (33). For individual examiners, the morphologic diagnosis assigned to needle biopsy specimens agreed with the morphologic diagnosis assigned to wedge biopsy specimens for 56 and 67% of the specimens. All 3 examiners agreed on the morphologic diagnosis assigned to needle and wedge biopsy specimens for 44 and 65% of the specimens, respectively. Morphologic diagnoses assigned to needle biopsy specimens concurred with the definitive diagnosis for 59 of 124 (48%) animals. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that needle biopsy specimens of the liver from dogs and cats must be interpreted with caution.     

Duodenal obstruction caused by infection with Pythium insidiosum in a 12-week-old puppy

Pythium insidiosum is an aquatic fungus-like organism that causes a serious chronic granulomatous disease called pythiosis in animals and humans in tropical and subtropical regions of the world. In North America, pythiosis is most often diagnosed in the Gulf Coast states. Early recognition of the disease is crucial to successful treatment, which includes surgical resection of granulomatous lesions and administration of antifungal agents. Despite increasing availability of diagnostic tests, intestinal pythiosis is insidious and is often not detected until lesions are extensive. Intestinal pythiosis was diagnosed in a 12-week-old puppy from South Carolina examined because of vomiting, diarrhea, and anorexia. Pythiosis was not initially suspected because of the young age of the patient and because pythiosis is uncommon in this area.     

Microorganisms associated with a pneumonic epizootic in Rocky Mountain bighorn sheep (Ovis canadensis canadensis).

A comprehensive study of a pneumonic epizootic was initiated when the first signs of disease were noted in a metapopulation of bighorn sheep inhabiting Hells Canyon, bordering Idaho, Oregon, and Washington. A total of 92 bighorn sheep were tested for etiologic agents during the following 6-mo study period. The study population included bighorn sheep believed to be the subpopulation in which disease was first noted, and these sheep were translocated to a holding facility in an effort to contain the disease (group A1, n = 72); bighorn sheep in other subpopulations (group A2) with evidence of clinical disease were captured, sampled, given antibiotics, and released (n = 8) and those that were found dead were necropsied (n = 12). Samples, including oropharyngeal and nasal swabs, and lung and liver tissue were collected from the bighorn sheep identified above. Tissue was collected at necropsy from 60 group A1 bighorn sheep that died following translocation, and samples were cultured for bacteria and viruses. Blood samples were tested for antibodies against known respiratory viruses, and histopathology was conducted on tissue samples. The major cause of death in both group A1 and group A2 bighorn sheep was a rapidly developing fibrinous bronchopneumonia. Multiple biovariants of Pasteurella were isolated from oropharyngeal and nasal samples from both groups, and Mycoplasma ovipneumonia was isolated from five group A1 oropharyngeal samples. Organisms isolated from lung tissue included Pasteurella multocida multocida a and Pasteurella trehalosi, both of which differentiated into multiple strains by restriction enzyme analysis, and parainfluenza-3 virus (PI-3). Paired serum samples revealed > fourfold increases in titers against PI-3 and bovine respiratory syncytial viruses. It was concluded that this epizootic resulted from a complex of factors including multiple potential respiratory pathogens, none of which were identified as a primary pathogen, and possible stress factors.     

A splendid tree frog with edema syndrome and intestinal adenocarcinoma.

A splendid tree frog (Pelodryas splendida) presented with subcutaneous edema extending along its dorsum from head to vent, which resolved with improvement of ambient temperature and humidity conditions in its enclosure. Four months later, this same frog presented in a moribund state with intracoelomic fluid accumulation. An intestinal adenocarcinoma, a rarely reported neoplasm in amphibians, was diagnosed post mortem. Neoplasia is one of a number of causes of edema syndrome, which is a nonspecific response to disease and debility in anurans.     

Preliminary tests of a new reversible male contraceptive in bush dog, Speothos venaticus: open-ended vasectomy and microscopic reversal.

Open-ended vasectomies were performed on four male bush dogs (Speothos venaticus), with three having microscopic reversal surgery (vasovasostomy) between 10 and 20 mo post-vasectomy. The key to ease of reversal is leaving the distal (testicular) end open to allow leakage, resulting in a pressure-relieving granuloma. The proximal (abdominal) end is cauterized, providing an effective seal. This technique prevents the buildup of pressure in the epididymis, therefore limiting damage to the male's reproductive capacity. Described here are detailed procedures for both surgeries. One of the three males that underwent vasovasostomy has successfully impregnated his female partner. This study demonstrates that these techniques can be successfully applied to animals. With the two remaining pairs, none of the four individuals were proven breeders prior to the study, so it is not possible to eliminate the possibility of previously existing infertility. This technique may have limited application for carnivores, because vasectomy does not prevent potential adverse effects to females from prolonged, cyclic exposure to endogenous progesterone. In other taxonomic groups (e.g., primates, ungulates, marsupials, and rodents) in which multimale groupings are common, this reversible male sterilization technique could provide managers with the ability to control which males reproduce without eliminating their future reproductive capacity or social interaction.