Investigation of the Molecular Detection of Vaccine-Derived Equine Herpesvirus Type 1 in Blood and Nasal Secretions from Horses Following Intramuscular Vaccination

Nicola Pusterla, Kristin P. Chaney, Roger Maes, Annabel G. Wise, Robert Holland, Hal C. Schott

Research output: Contribution to journalArticle

1 Citation (Scopus)

Abstract

The objective of this study was to investigate whether intramuscular vaccination of healthy adult horses with a killed or a modified live equine herpesvirus type 1 (EHV-1) vaccine could induce transient positive PCR results in either blood or secretions collected on a nasopharyngeal swab. Four horses in each group received either a single killed or a modified-live vaccine intramuscularly. Two local commingled and 2 distant nonvaccinated controls were included for each group. All horses were observed daily for evidence of clinical abnormalities throughout the study periods. Blood and nasopharyngeal swabs were collected twice before vaccination and once weekly for 4 weeks after vaccination and submitted for PCR testing for EHV-1 by 2 independent laboratories using different real-time PCR methodologies. Serum samples collected from all horses on the vaccination day and 21 days later were tested for antibodies against EHV-1 using a serum neutralization test. Whereas the 2 vaccine strains tested positive in both EHV-1 PCR assays, nasopharyngeal swabs and whole blood collected from vaccinated and control horses had negative PCR test results for EHV-1 during the entire study period. Serum neutralization testing revealed a 2- to 4-fold increase in titers for all vaccinated horses, whereas titers in control horses were largely unchanged. The use of seropositive horses before immunization and the sampling frequency of 7 days may have prevented the occasional molecular detection of the vaccine virus in whole blood and nasopharyngeal secretions. However, the study results demonstrate that detection of EHV-1 DNA by PCR in vaccinated and unvaccinated healthy horses is not a common event.

Original languageEnglish (US)
Pages (from-to)290-293
Number of pages4
JournalJournal of Veterinary Diagnostic Investigation
Volume19
Issue number3
DOIs
StatePublished - 2007

Fingerprint

Equid Herpesvirus 1
Equid herpesvirus 1
Synthetic Vaccines
Nose
Horses
Vaccination
vaccination
secretion
vaccines
horses
blood
Polymerase Chain Reaction
blood serum
Herpesvirus Vaccines
Rhadinovirus
Vaccines
Serum
Neutralization Tests
testing
live vaccines

Keywords

  • EHV-1
  • healthy horses
  • PCR detection
  • vaccine

ASJC Scopus subject areas

  • veterinary(all)
  • Microbiology

Cite this

Investigation of the Molecular Detection of Vaccine-Derived Equine Herpesvirus Type 1 in Blood and Nasal Secretions from Horses Following Intramuscular Vaccination. / Pusterla, Nicola; Chaney, Kristin P.; Maes, Roger; Wise, Annabel G.; Holland, Robert; Schott, Hal C.

In: Journal of Veterinary Diagnostic Investigation, Vol. 19, No. 3, 2007, p. 290-293.

Research output: Contribution to journalArticle

@article{b28dafd43e2c4cfd9f8391fa4389ee59,
title = "Investigation of the Molecular Detection of Vaccine-Derived Equine Herpesvirus Type 1 in Blood and Nasal Secretions from Horses Following Intramuscular Vaccination",
abstract = "The objective of this study was to investigate whether intramuscular vaccination of healthy adult horses with a killed or a modified live equine herpesvirus type 1 (EHV-1) vaccine could induce transient positive PCR results in either blood or secretions collected on a nasopharyngeal swab. Four horses in each group received either a single killed or a modified-live vaccine intramuscularly. Two local commingled and 2 distant nonvaccinated controls were included for each group. All horses were observed daily for evidence of clinical abnormalities throughout the study periods. Blood and nasopharyngeal swabs were collected twice before vaccination and once weekly for 4 weeks after vaccination and submitted for PCR testing for EHV-1 by 2 independent laboratories using different real-time PCR methodologies. Serum samples collected from all horses on the vaccination day and 21 days later were tested for antibodies against EHV-1 using a serum neutralization test. Whereas the 2 vaccine strains tested positive in both EHV-1 PCR assays, nasopharyngeal swabs and whole blood collected from vaccinated and control horses had negative PCR test results for EHV-1 during the entire study period. Serum neutralization testing revealed a 2- to 4-fold increase in titers for all vaccinated horses, whereas titers in control horses were largely unchanged. The use of seropositive horses before immunization and the sampling frequency of 7 days may have prevented the occasional molecular detection of the vaccine virus in whole blood and nasopharyngeal secretions. However, the study results demonstrate that detection of EHV-1 DNA by PCR in vaccinated and unvaccinated healthy horses is not a common event.",
keywords = "EHV-1, healthy horses, PCR detection, vaccine",
author = "Nicola Pusterla and Chaney, {Kristin P.} and Roger Maes and Wise, {Annabel G.} and Robert Holland and Schott, {Hal C.}",
year = "2007",
doi = "10.1177/104063870701900311",
language = "English (US)",
volume = "19",
pages = "290--293",
journal = "Journal of Veterinary Diagnostic Investigation",
issn = "1040-6387",
publisher = "American Association of Veterinary Laboratory Diagnosticians",
number = "3",

}

TY - JOUR

T1 - Investigation of the Molecular Detection of Vaccine-Derived Equine Herpesvirus Type 1 in Blood and Nasal Secretions from Horses Following Intramuscular Vaccination

AU - Pusterla, Nicola

AU - Chaney, Kristin P.

AU - Maes, Roger

AU - Wise, Annabel G.

AU - Holland, Robert

AU - Schott, Hal C.

PY - 2007

Y1 - 2007

N2 - The objective of this study was to investigate whether intramuscular vaccination of healthy adult horses with a killed or a modified live equine herpesvirus type 1 (EHV-1) vaccine could induce transient positive PCR results in either blood or secretions collected on a nasopharyngeal swab. Four horses in each group received either a single killed or a modified-live vaccine intramuscularly. Two local commingled and 2 distant nonvaccinated controls were included for each group. All horses were observed daily for evidence of clinical abnormalities throughout the study periods. Blood and nasopharyngeal swabs were collected twice before vaccination and once weekly for 4 weeks after vaccination and submitted for PCR testing for EHV-1 by 2 independent laboratories using different real-time PCR methodologies. Serum samples collected from all horses on the vaccination day and 21 days later were tested for antibodies against EHV-1 using a serum neutralization test. Whereas the 2 vaccine strains tested positive in both EHV-1 PCR assays, nasopharyngeal swabs and whole blood collected from vaccinated and control horses had negative PCR test results for EHV-1 during the entire study period. Serum neutralization testing revealed a 2- to 4-fold increase in titers for all vaccinated horses, whereas titers in control horses were largely unchanged. The use of seropositive horses before immunization and the sampling frequency of 7 days may have prevented the occasional molecular detection of the vaccine virus in whole blood and nasopharyngeal secretions. However, the study results demonstrate that detection of EHV-1 DNA by PCR in vaccinated and unvaccinated healthy horses is not a common event.

AB - The objective of this study was to investigate whether intramuscular vaccination of healthy adult horses with a killed or a modified live equine herpesvirus type 1 (EHV-1) vaccine could induce transient positive PCR results in either blood or secretions collected on a nasopharyngeal swab. Four horses in each group received either a single killed or a modified-live vaccine intramuscularly. Two local commingled and 2 distant nonvaccinated controls were included for each group. All horses were observed daily for evidence of clinical abnormalities throughout the study periods. Blood and nasopharyngeal swabs were collected twice before vaccination and once weekly for 4 weeks after vaccination and submitted for PCR testing for EHV-1 by 2 independent laboratories using different real-time PCR methodologies. Serum samples collected from all horses on the vaccination day and 21 days later were tested for antibodies against EHV-1 using a serum neutralization test. Whereas the 2 vaccine strains tested positive in both EHV-1 PCR assays, nasopharyngeal swabs and whole blood collected from vaccinated and control horses had negative PCR test results for EHV-1 during the entire study period. Serum neutralization testing revealed a 2- to 4-fold increase in titers for all vaccinated horses, whereas titers in control horses were largely unchanged. The use of seropositive horses before immunization and the sampling frequency of 7 days may have prevented the occasional molecular detection of the vaccine virus in whole blood and nasopharyngeal secretions. However, the study results demonstrate that detection of EHV-1 DNA by PCR in vaccinated and unvaccinated healthy horses is not a common event.

KW - EHV-1

KW - healthy horses

KW - PCR detection

KW - vaccine

UR - http://www.scopus.com/inward/record.url?scp=34250688742&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=34250688742&partnerID=8YFLogxK

U2 - 10.1177/104063870701900311

DO - 10.1177/104063870701900311

M3 - Article

C2 - 17459860

AN - SCOPUS:34250688742

VL - 19

SP - 290

EP - 293

JO - Journal of Veterinary Diagnostic Investigation

JF - Journal of Veterinary Diagnostic Investigation

SN - 1040-6387

IS - 3

ER -