Search Results

You are looking at 1 - 5 of 5 items for

  • Author or Editor: Michael Niezgoda x
  • Refine by Access: All Content x
Clear All Modify Search

Abstract

Objective—To evaluate postexposure prophylaxis (PEP) in dogs experimentally infected with rabies.

Procedure—29 Beagles.

Procedure—Dogs were sedated and inoculated in the right masseter muscle with a salivary gland homogenate from a naturally infected rabid dog (day 0). Six hours later, 5 dogs were treated by administration of 2 murine anti-rabies glycoprotein monoclonal antibodies (mAb) and commercial vaccine; 5 received mAb alone; 5 received purified, heat-treated, equine rabies immune globulin (PHT-ERIG) and vaccine; 5 received PHT-ERIG alone; 4 received vaccine alone; and 5 control dogs were not treated. The mAb or PHTERIG was administered at the site of rabies virus inoculation. Additional vaccine doses for groups mAb plus vaccine, PHT-ERIG plus vaccine, and vaccine alone were administered IM in the right hind limb on days 3, 7, 14, and 35.

Results—All control dogs and dogs that received only vaccine developed rabies. In the PHT-ERIG and vaccine group, 2 of 5 dogs were protected, whereas none were protected with PHT-ERIG alone. Use of mAb alone resulted in protection in 4 of 5 dogs. Administration of mAb in combination with vaccine provided protection in all 5 dogs.

Conclusions and Clinical Relevance—Current national guidelines recommend euthanasia or a 6- month quarantine for unvaccinated animals exposed to rabies. Findings from this study document that vaccine alone following severe exposure was unable to provide protection from rabies. However, vaccine combined with mAb resulted in protection in all treated dogs, revealing the potential use of mAb in PEP against rabies in naïve dogs. (Am J Vet Res 2002;63:1096–1100)

Full access
in American Journal of Veterinary Research

Abstract

Objective

To determine susceptibility, incubation and morbidity periods, clinical signs of infection, serologic response, and excretion of virus in domestic ferrets inoculated with rabies virus of raccoon origin.

Animals

54 domestic ferrets.

Procedure

5 groups of ferrets were inoculated IM with the rabies virus. Oral cavity swab specimens and saliva were obtained for virus isolation. Blood was obtained for virus-neutralizing antibody determination. If clinical signs were severe, ferrets were euthanatized immediately. Salivary gland and brain tissue was collected for virus isolation and rabies diagnosis, respectively.

Results

Of 51 inoculated ferrets, 19 (37%) were euthanatized with clinical signs of rabies. Mean incubation period was 28 days (range, 17 to 63 days). Clinical signs included ataxia, cachexia, inactivity, paresis, paraparesis, bladder atony, tremors, hypothermia, lethargy, constipation, paralysis, and anorexia. Two rabid ferrets manifested aggressive behavior. Mean morbidity period was 4 to 5 days (range, 1 to 8 days). Virus antigen was detected in brain tissue from all rabid ferrets (n = 19). Two rabid ferrets had detectable virus-neutralizing antibody. Of 32 ferrets that survived, only 1 seroconverted; survivors remained clinically normal throughout the observation period. Rabies virus was isolated from salivary glands of 12 of 19 (63%) rabid ferrets, and 9 (47%) shed virus in saliva. Initiation of virus excretion ranged from 2 days before onset of illness to 6 days after onset.

Conclusions and Clinical Relevance

Rabies should be considered in the differential diagnosis for ferrets that have acute onset of paralysis or behavioral changes and a condition that rapidly deteriorates despite intense medical intervention. (Am J Vet Res 1998;59:1629-1632)

Free access
in American Journal of Veterinary Research

Abstract

CASE DESCRIPTION A female alpaca, kept at pasture with 12 other female alpacas, 2 crias, and 5 goats, was evaluated because of clinical signs of aggression.

CLINICAL FINDINGS The clinical signs of aggression progressed to include biting at other animals as well as disorientation. Three days later, the alpaca was euthanized because of suspicion of rabies virus infection.

TREATMENT AND OUTCOME No physical injuries were found at necropsy. Brain tissue specimens were confirmed positive for rabies on the basis of direct fluorescent antibody test results. Molecular typing identified the rabies virus variant as one that is enzootic in raccoons. The farm was placed under quarantine, restricting movement of animals on and off the property for 6 months. To prevent further rabies cases, 14 alpacas (12 adults and 2 crias) were vaccinated by extralabel use of a large animal rabies vaccine. Of the 14 vaccinated alpacas, 8 had paired serum samples obtained immediately before and 21 days after vaccination; all 8 alpacas had adequate serum antirabies antibody production in response to rabies vaccination. As a result of an adequate serologic response, the quarantine was reduced to 3 months. In the year after the index rabies case, no other animals on the farm developed rabies.

CLINICAL RELEVANCE Extralabel use of rabies vaccines in camelids was used in the face of a public health investigation. This report provides an example of handling of a rabies case for future public health investigations, which will undoubtedly need to develop ad-hoc rabies vaccination recommendations on the basis of the unique characteristics of the event.

Full access
in Journal of the American Veterinary Medical Association

SUMMARY

Objective

To determine susceptibility, incubation and morbidity periods, clinical signs, serologic response, and excretion of virus in domestic ferrets inoculated with rabies virus.

Animals

55 domestic ferrets.

Procedure

5 groups of 10 ferrets were inoculated with rabies virus, IM, at doses of 105.5 to 101.5 median mouse intracerebral lethal dose. Ferrets were observed and behavior was recorded. Rectal temperature, body weight, and samples from the oral cavity and samples of saliva and blood were obtained. Virus isolation was attempted, using intracranial mouse inoculation and cell culture. Virus neutralizing antibodies were determined by rapid fluorescent focus inhibition test. Ferrets were euthanatized immediately if clinical signs were severe. Rabies was confirmed by direct immunofluorescent antibody test.

Results

Mean incubation period was 33 days (range, 16 to 96 days). Clinical signs included ascending paralysis, ataxia, cachexia, bladder atony, fever, hyperactivity, tremors, and paresthesia. Mean morbidity period was 4 to 5 days (range, 2 to 10 days). Virus antigen was detected in brain tissue from all clinically rabid ferrets. Ferrets given the highest viral dose were euthanatized and had VNA; ferrets receiving the next dilution also were euthanatized, but only 4 had seroconverted. Of 17 ferrets that survived, 5 seroconverted. Survivors remained clinically normal except for 1 that recovered with severe paralytic sequelae. Rabies virus was isolated from the salivary gland of 1 ferret that was euthanatized.

Conclusions and Clinical Relevance

Rabies should be considered as a differential diagnosis in any ferret that has acute onset of paralysis or behavioral changes and a condition that rapidly deteriorates despite intense medical intervention. (Am J Vet Res 1997;58:1327–1331)

Free access
in American Journal of Veterinary Research

Objective

To evaluate the use of bait containing rabies vaccine to create a barrier of rabies-vaccinated raccoons in Massachusetts and to determine the effectiveness of various bait distribution strategies in halting the spread of rabies.

Design

Prospective study.

Sample Population

Free-ranging raccoons.

Procedure

Baits were distributed twice yearly in a 207-km2 (80-mi2) area in the vicinity of the Cape Cod Canal. Bait density and distribution strategy varied among 3 treatment areas. Raccoons were caught in live traps after bait distribution and anesthetized; blood samples were obtained to measure serum antibody titers to rabies virus. Vaccination rates were determined by the percentage of captured raccoons with antibody titers to rabies virus ≥ 1:5. In addition, raccoons with clinical signs of illness inside the vaccination zone and adjacent areas were euthanatized and submitted for rabies testing.

Results

The percentage of vaccinated raccoons differed significantly among the following 3 areas with various bait densities: high-density area with uniform bait distribution (103 baits/km2 [267 baits/mi2]) = 37%; low-density area with additional targeted bait distribution (93 baits/km2 [240 baits/mi2]) = 67%; and, high-density area with additional targeted bait distribution (135 baits/km2 [350 baits/mi2]) = 77%. Nineteen animals with rabies (15 raccoons, 3 skunks, 1 cat) were reported in the area just outside of the vaccination zone, but only 1 raccoon with rabies was reported from inside the vaccination zone.

Clinical Implications

In this suburban study area, an approximate vaccination rate of 63% was sufficient to halt the spread of rabies in free-ranging raccoons. Compared with uniform bait distribution, targeting raccoon habitats increased vaccination rates. (J Am Vet Med Assoc 1998;213:1407-1412)

Free access
in Journal of the American Veterinary Medical Association