Search Results

Abstract

Objective—To determine whether passive transfer of immunity affects results of diagnostic tests for antibodies against FIV in kittens born to vaccinated queens.

Design—Experimental trial.

Animals—12 specific-pathogen-free queens and their 55 kittens.

Procedure—Queens were vaccinated with a wholevirus FIV vaccine prior to breeding. Serum was obtained from the queens on the day of parturition and from the kittens on days 2 and 7, then weekly until results of tests for antibodies against FIV were negative for 2 consecutive weeks. Milk was collected from the queens daily for the first week and then weekly. Serum and milk were tested for antibodies against FIV with 2 commercial assays.

Results—Antibodies against FIV were detected in serum obtained from the queens on the day of parturition and in the milk throughout lactation. All kittens tested positive for antibodies against FIV at 2 days of age. At 8 weeks of age, 30 (55%) kittens tested positive with 1 of the commercial assays, and 35 (64%) tested positive with the other. All kittens tested negative for antibodies against FIV by 12 weeks of age.

Conclusions and Clinical Relevance—Results suggest that kittens readily absorb antibodies against FIV in colostrum from vaccinated queens and that these antibodies may interfere with results of commercially available tests for FIV infection past the age of weaning. Currently licensed diagnostic tests for FIV infection are unable to distinguish among kittens with antibodies against FIV as a result of infection, passive transfer from infected queens, and passive transfer from vaccinated queens. (J Am Vet Med Assoc 2004;225:1554–1557)

Abstract

Objective—To determine the frequency and duration of feline panleukopenia virus (FPV) vaccine-induced interference with fecal parvovirus diagnostic testing in cats.

Design—Prospective controlled study.

Animals—Sixty-four 8- to 10-week-old specific-pathogen–free kittens.

Procedures—Kittens were inoculated once with 1 of 8 commercial multivalent vaccines containing modified-live virus (MLV) or inactivated FPV by the SC or intranasal routes. Feces were tested for parvovirus antigen immediately prior to vaccination, then daily for 14 days with 3 tests designed for detection of canine parvovirus. Serum anti-FPV antibody titers were determined by use of hemagglutination inhibition prior to vaccination and 14 days later.

Results—All fecal parvovirus test results were negative prior to vaccination. After vaccination, 1 kitten had positive test results with test 1, 4 kittens had positive results with test 2, and 13 kittens had positive results with test 3. Only 1 kitten had positive results with all 3 tests, and only 2 of those tests were subjectively considered to have strongly positive results. At 14 days after vaccination, 31% of kittens receiving inactivated vaccines had protective FPV titers, whereas 85% of kittens receiving MLV vaccines had protective titers.

Conclusions and Clinical Relevance—Animal shelter veterinarians should select fecal tests for parvovirus detection that have high sensitivity for FPV and low frequency of vaccine-related test interference. Positive parvovirus test results should be interpreted in light of clinical signs, vaccination history, and results of confirmatory testing. Despite the possibility of test interference, the benefit provided by universal MLV FPV vaccination of cats in high-risk environments such as shelters outweighs the impact on diagnostic test accuracy.

Abstract

Objective—To determine the frequency of enteropathogens in cats entering an animal shelter with normal feces or diarrhea.

Design—Cross-sectional study.

Animals—100 cats evaluated at an open-admission municipal animal shelter in Florida.

Procedures—Fecal samples collected within 24 hours after admission from 50 cats with normal feces and 50 cats with diarrhea were tested by fecal flotation, antigen testing, PCR assay, and electron microscopy for selected enteropathogens.

Results—12 enteropathogens were identified. Cats with diarrhea were no more likely to be infected with ≥ 1 (84%) enteropathogens than were cats with normal feces (84%). Only feline coronavirus was significantly more prevalent in cats with diarrhea (58%) than in cats with normal feces (36%). Other enteropathogens identified in cats with and without diarrhea included Clostridium perfringens enterotoxin A (42% and 50%, respectively), Cryptosporidium spp (10% and 20%, respectively), Giardia spp (20% and 8%, respectively), Cystoisospora spp (14% and 10%, respectively), hookworms (10% and 18%, respectively), ascarids (6% and 16%, respectively), Salmonella spp (6% and 4%, respectively), astrovirus (8% and 2%, respectively), feline panleukopenia virus (4% and 4%, respectively), calicivirus (0% and 2%, respectively), and Spirometra spp (0% and 2%, respectively).

Conclusions and Clinical Relevance—In the present study, cats entered the shelter with a variety of enteropathogens, many of which are pathogenic or zoonotic. Most infections were not associated with diarrhea or any specific risk factors such as signalment, source, or body condition, making it difficult to predict which cats were most likely to be infected. It is not possible to test all shelter cats for all possible infections, so practical guidelines should be developed to treat routinely for the most common and important enteropathogens.

Abstract

Objective—To determine the frequency of enteropathogens in dogs entering an animal shelter with normal feces or diarrhea.

Design—Cross-sectional study.

Animals—100 dogs evaluated at an open-admission municipal animal shelter in Florida.

Procedures—Fecal samples were collected within 24 hours after admission from 50 dogs with normal feces and 50 dogs with diarrhea. Feces were tested by fecal flotation, antigen testing, PCR assay, and electron microscopy for selected enteropathogens.

Results—13 enteropathogens were identified. Dogs with diarrhea were significantly more likely to be infected with ≥ 1 enteropathogens (96%) than were dogs with normal feces (78%). Only Clostridium perfringens enterotoxin A gene was significantly more common in dogs with diarrhea (64%) than in dogs with normal feces (40%). Other enteropathogens identified in dogs with and without diarrhea included hookworms (58% and 48%, respectively), Giardia spp (22% and 16%, respectively), canine enteric coronavirus (2% and 18%, respectively), whipworms (12% and 8%, respectively), Cryptosporidium spp (12% and 2%, respectively), ascarids (8% and 8%, respectively), Salmonella spp (2% and 6%, respectively), Cystoisospora spp (2% and 4%, respectively), canine distemper virus (8% and 0%, respectively), Dipylidium caninum (2% and 2%, respectively), canine parvovirus (2% and 2%, respectively), and rotavirus (2% and 0%, respectively).

Conclusions and Clinical Relevance—Dogs entered the shelter with a variety of enteropathogens, many of which are pathogenic or zoonotic. Most infections were not associated with diarrhea or any specific dog characteristics, making it difficult to predict the risk of nfection for individual animals. Guidelines for preventive measures and empirical treatments that are logistically and financially feasible for use in shelters should be developed for control of the most common and important enteropathogens.

Abstract

OBJECTIVE To determine the seroprevalence of heartworm infection, risk factors for seropositivity, and frequency of prescribing heartworm preventives for cats.

DESIGN Prospective cross-sectional study.

ANIMALS 34,975 cats from 1,353 veterinary clinics (n = 26,707) and 125 animal shelters (8,268) in the United States and Canada.

PROCEDURES Blood samples were collected from all cats and tested with a point-of-care ELISA for Dirofilaria immitis antigen, FeLV antigen, and FIV antibody. Results were compared among geographic regions and various cat groupings.

RESULTS Seropositivity for heartworm antigen in cats was identified in 35 states but not in Canada; overall seroprevalence in the United States was 0.4%. Seroprevalence of heartworm infection was highest in the southern United States. A 3-fold increase in the proportion of seropositive cats was identified for those with (vs without) outdoor access, and a 2.5-fold increase was identified for cats that were unhealthy (vs healthy) when tested. Seroprevalence was 0.3% in healthy cats, 0.7% in cats with oral disease, 0.9% in cats with abscesses or bite wounds, and 1.0% in cats with respiratory disease. Coinfection with a retrovirus increased the risk of heartworm infection. Heartworm preventives were prescribed for only 12.6% of cats at testing, and prescribing was more common in regions with a higher seroprevalence.

CONCLUSIONS AND CLINICAL RELEVANCE At an estimated prevalence of 0.4%, hundreds of thousands of cats in the United States are likely infected with heartworms. Given the difficulty in diagnosing infection at all clinically relevant parasite stages and lack of curative treatment options, efforts should be increased to ensure all cats receive heartworm preventives.

Abstract

Objective—To determine the effects of anesthesia and surgery on serologic responses to vaccination in kittens.

Design—Prospective controlled trial.

Animals—32 specific-pathogen–free kittens.

Procedures—Kittens were assigned to 1 of 4 treatment groups: neutering at 7, 8, or 9 weeks of age or no neutering. All kittens were inoculated with modified-live virus vaccines against feline panleukopenia virus (FPV), feline herpesvirus (FHV), and feline calicivirus (FCV) at 8, 11, and 14 weeks of age and inactivated rabies virus (RV) at 14 weeks of age. Serum antibody titers against FPV, FHV, and FCV were determined at 8, 9, 11, 14, and 17 weeks of age; RV titers were determined at 14 and 17 weeks of age.

Results—Serologic responses of kittens neutered at the time of first vaccination (8 weeks) were not different from those of kittens neutered 1 week before (7 weeks) or 1 week after (9 weeks) first vaccination or from those of kittens that were not neutered. In total, 31%, 0%, 69%, and 9% of kittens failed to develop adequate titers against FPV, FCV, FHV, and RV, respectively, by 17 weeks of age.

Conclusions and Clinical Relevance—Neutering at or near the time of first vaccination with a modified-live virus vaccine did not impair antibody responses in kittens. Many kittens that were last vaccinated at 14 weeks of age had inadequate antibody titers at 17 weeks of age. Kittens may be vaccinated in the perioperative period when necessary, and the primary vaccination series should be extended through at least 16 weeks of age.

Abstract

Objective—To determine the proportion of cats entering a Florida animal shelter with serum antibody titers against feline panleukopenia virus (FPV), feline herpesvirus 1 (FHV1), and feline calicivirus (FCV) and to identify factors associated with seropositivity.

Design—Cross-sectional study.

Animals—347 cats admitted to a Florida animal shelter.

Procedures—Within 24 hours after admission to the animal shelter, blood samples were collected from all cats ≥ 8 weeks of age. Serum antibody titers against FPV were determined via a hemagglutination inhibition assay, and those against FHV1 and FCV were determined via virus neutralization assays. Age, sex, environment (urban or rural), source (stray or previously owned), evidence of previous caregiving, health status (healthy or not healthy), and outcome (adoption, transfer, return to owner, or euthanasia) were evaluated as potential factors associated with antibody seropositivity.

Results—Of 347 cats, 138 (39.8%), 38 (11.0%), and 127 (36.6%) had antibody titers ≥ 40, ≥ 8, and ≥ 32 (ie, seropositive) against FPV, FHV1, and FCV, respectively. Factors associated with seropositivity included being neutered, age ≥ 6 months, and being relinquished by an owner. On multivariable analysis, health status at shelter admission, environment, vaccination at shelter admission, and outcome were not associated with seropositivity.

Conclusions and Clinical Relevance—Most cats were seronegative for antibodies against FPV, FHV1, and FCV at the time of admission to an animal shelter. These findings supported current guidelines that recommend vaccination of all cats immediately after admission to animal shelters, regardless of the source or physical condition.

Abstract

Objective—To characterize retroviruses isolated from boid snakes with inclusion body disease (IBD).

Animals—2 boa constrictors with IBD and 1 boa exposed to an affected snake.

Procedure—Snakes were euthanatized, and tissue specimens and blood samples were submitted for virus isolation. Tissue specimens were cultured with or without commercially available viper heart cells and examined by use of transmission electron microscopy (TEM) for evidence of viral replication. Reverse transcriptase activity was determined in sucrose gradient-purified virus. Western blotting was performed, using polyclonal antibodies against 1 of the isolated viruses. Specificity of the rabbit anti-virus antibody was evaluated, using an immunogold-labeling TEM technique.

Results—3 viruses (RV-1, RV-2, and RV-3) were isolated. The isolates were morphologically comparable to members of the Retroviridae family. Reverse transcriptase activity was high in sucrose gradient fractions that were rich in virus. Polyclonal antibody against RV-1 reacted with proteins of similar relative mobility in RV-1 and RV-2. By use of immunogold labeling, this antibody also recognized virions of both RV-1 and RV-2.

Conclusions and Clinical Relevance—A retrovirus was isolated from boid snakes with IBD or exposed to IBD. Western blot analysis of viral proteins indicated that viruses isolated from the different snakes were similar. Whether this virus represents the causative agent of IBD is yet to be determined. The isolation of retroviruses from boid snakes with IBD is an important step in the process of identifying the causative agent of this disease. (Am J Vet Res 2001;62:217–224)

Abstract

OBJECTIVE To estimate seroprevalences for FeLV antigen and anti-FIV antibody and risk factors for seropositivity among cats in the United States and Canada.

DESIGN Cross-sectional study.

ANIMALS 62,301 cats tested at 1,396 veterinary clinics (n = 45,406) and 127 animal shelters (16,895).

PROCEDURES Blood samples were tested with a point-of-care ELISA for FeLV antigen and anti-FIV antibody. Seroprevalence was estimated, and risk factors for seropositivity were evaluated with bivariate and multivariable mixed-model logistic regression analyses adjusted for within-clinic or within-shelter dependencies.

RESULTS Overall, seroprevalence was 3.1% for FeLV antigen and 3.6% for anti-FIV antibody. Adult age, outdoor access, clinical disease, and being a sexually intact male were risk factors for seropositivity for each virus. Odds of seropositivity for each virus were greater for cats tested in clinics than for those tested in shelters. Of 1,611 cats with oral disease, 76 (4.7%) and 157 (9.7%) were seropositive for FeLV and FIV, respectively. Of 4,835 cats with respiratory disease, 385 (8.0%) were seropositive for FeLV and 308 (6.4%) were seropositive for FIV. Of 1,983 cats with abscesses or bite wounds, 110 (5.5%) and 247 (12.5%) were seropositive for FeLV and FIV, respectively. Overall, 2,368 of 17,041 (13.9%) unhealthy cats were seropositive for either or both viruses, compared with 1,621 of 45,260 (3.6%) healthy cats.

CONCLUSIONS AND CLINICAL RELEVANCE Seroprevalences for FeLV antigen and anti-FIV antibody were similar to those reported in previous studies over the past decade. Taken together, these results indicated a need to improve compliance with existing guidelines for management of feline retroviruses.

Abstract

Objective—To determine whether administration of inactivated virus or modified-live virus (MLV) vaccines to feral cats at the time of neutering induces protective serum antiviral antibody titers.

Design—Prospective study.

Animals—61 feral cats included in a trap-neuter-return program in Florida.

Procedures—Each cat received vaccines against feline panleukopenia virus (FPV), feline herpes virus (FHV), feline calicivirus (FCV), FeLV, and rabies virus (RV). Immediately on completion of surgery, vaccines that contained inactivated RV and FeLV antigens and either MLV or inactivated FPV, FHV, and FCV antigens were administered. Titers of antiviral antibodies (except those against FeLV) were assessed in serum samples obtained immediately prior to surgery and approximately 10 weeks later.

Results—Prior to vaccination, some of the cats had protective serum antibody titers against FPV (33%), FHV (21%), FCV (64%), and RV (3%). Following vaccination, the overall proportion of cats with protective serum antiviral antibody titers increased (FPV [90%], FHV [56%], FCV [93%], and RV [98%]). With the exception of the FHV vaccine, there were no differences in the proportions of cats protected with inactivated virus versus MLV vaccines.

Conclusions and Clinical Relevance—Results suggest that exposure to FPV, FHV, and FCV is common among feral cats and that a high proportion of cats are susceptible to RV infection. Feral cats appeared to have an excellent immune response following vaccination at the time of neutering. Incorporation of vaccination into trap-neuter-return programs is likely to protect the health of individual cats and possibly reduce the disease burden in the community.