Antibody Detection for Parvovirus and Distemper Virus

The Research Questions

  • Is it feasible for shelters to use antibody titer testing to determine individual dogs’ risk of contracting disease in the face of an outbreak?
  • Which test(s) is/are most appropriate for shelters to use?

Background

Canine Distemper Virus and Canine Parvovirus are highly contagious diseases that can be a death sentence for many dogs during shelter outbreaks. Fortunately, past exposure to the viruses as well as vaccination can protect dogs from getting ill. There are several tests to determine antibody levels in individual dogs to determine their risk of contracting Distemper Virus or Parvovirus in the event of a disease outbreak, and it’s important for shelters to be able to make educated decisions about which tests to choose.

It is my hope that the results of this research can influence shelters to implement titer testing during disease outbreaks so that as many dogs as possible may be saved.

Lauren Gray

Maddie’s® Researcher

UF CVM Class of 2013

Without the ability to determine antibody titer levels, shelter veterinarians may have no way of knowing which dogs may be protected from disease during outbreaks. In the past, this has led some shelters to depopulate, or euthanize all dogs that have been exposed to sick dogs in the shelter. Proper utilization of antibody titer testing can empower shelter veterinarians to triage dogs based on risk of contracting disease, meaning those that are most likely protected can be saved.

Abstract

Comparison of two assays for detection of antibodies against canine parvovirus and canine distemper virus in dogs admitted to a Florida animal shelter

Objective

To compare 2 assays for use in the identification of dogs with a protective antibody titer (PAT) against canine parvovirus (CPV) and canine distemper virus (CDV).

Design

Prospective cross-sectional study.

Animals

431 dogs admitted to a municipal animal shelter in north central Florida.

Procedures

Blood samples were collected from dogs on the day of admission to the shelter. Serum was obtained, criterion-referenced assays were used to identify dogs that had
PATs against CPV (titers ≥ 80; hemagglutination inhibition assay) and CDV (titers ≥ 32; virus neutralization assay), and results were compared with results of a semiquantitative ELISA
and an immunofluorescence assay (IFA).

Results

For correct identification of dogs that had PATs against viruses, the ELISA had significantly higher specificity for CPV (98%) and CDV (95%) than did the IFA (82% and 70%, respectively) and had significantly lower sensitivity for CDV (88%) than did the IFA (97%); the sensitivity for CPV was similar (ELISA, 98%; IFA, 97%). Overall diagnostic accuracy was significantly greater with the ELISA than with the IFA. Predictive value of a positive result for PATs was significantly higher with the ELISA for CPV (99%) and CDV (93%) than with the IFA (92% and 71%, respectively).

Conclusions and Clinical Relevance

The ELISA had fewer false-positive results than did the IFA and could be performed on-site in shelters in < 1 hour. Accuracy and practicality of the ELISA may be useful for identifying the infection risk of dogs exposed during outbreaks attributable to CPV and CDV infections in shelters. (J Am Vet Med Assoc 2012;240:1084–1087)

Conclusions

Synbiotics TiterCHEK ELISA antibody titer test had fewer false-positive results than did the reference laboratory immunofluorescence assay, and can be performed on-site in shelters in less than 1 hour. Accuracy and practicality of the ELISA may be useful for identifying the infection risk of dogs exposed during Canine Parvovirus and Canine Distemper Virus outbreaks in shelters.

Read the complete paper.

This project was conducted by Lauren Gray, Maddie’s® Researcher, Class of 2013. Dr. Cynda Crawford mentored the project.  The researchers would like to thank the staff at Alachua County Animal Services for assistance with sample collection.  This project and Maddie’s® Shelter Medicine Program are underwritten by a grant from Maddie’s Fund®, The Pet Rescue Foundation, and the project was supported by the Morris Animal Foundation.

Ms. Gray’s poster presentation for this project won the award for best student poster presentation at UF’s 2011 Phi Zeta day.