Efficacy of a foot-and-mouth disease vaccine against a heterologous SAT1 virus challenge in goats

D D Lazarus; F Peta; D Blight; J Van Heerden; P B Mutowembwa; L Heath; B Blignaut; P A Opperman; G T Fosgate

doi:10.1016/j.vaccine.2020.04.014

Efficacy of a foot-and-mouth disease vaccine against a heterologous SAT1 virus challenge in goats

Vaccine. 2020 May 19;38(24):4006-4015. doi: 10.1016/j.vaccine.2020.04.014. Epub 2020 Apr 17.

Authors

D D Lazarus¹, F Peta², D Blight³, J Van Heerden², P B Mutowembwa², L Heath², B Blignaut⁴, P A Opperman³, G T Fosgate⁴

Affiliations

¹ University of Pretoria, Faculty of Veterinary Science, Department of Production Animal Studies, Onderstepoort, South Africa; National Veterinary Research Institute, Foot-and-Mouth Disease Virus Research Laboratory, Vom, Nigeria. Electronic address: dlazarus@nvri.gov.ng.
² Agricultural Research Council, Onderstepoort Veterinary Research, Transboundary Animal Diseases, Onderstepoort, South Africa.
³ University of Pretoria, Faculty of Veterinary Science, Department of Production Animal Studies, Onderstepoort, South Africa; Agricultural Research Council, Onderstepoort Veterinary Research, Transboundary Animal Diseases, Onderstepoort, South Africa.
⁴ University of Pretoria, Faculty of Veterinary Science, Department of Production Animal Studies, Onderstepoort, South Africa.

PMID: 32312581
DOI: 10.1016/j.vaccine.2020.04.014

Abstract

Goats are susceptible to infection with foot-and-mouth disease virus (FMDV), but their role in the epidemiology of the disease and response to vaccination is poorly understood. In southern Africa, FMDV serotypes Southern African Territories (SAT) 1, 2 and 3 are known to be endemic. In this study, we evaluated the efficacy of a pentavalent FMD vaccine in goats against heterologous challenge with a pool of field SAT1 FMDV. Forty FMD sero-negative goats (6-12 months of age) of mixed sexes were randomly allocated to one of five treatment groups: full cattle dose (2 ml), 1/3rd (0.67 ml), 1/6th (0.33 ml), 1/12th (0.16 ml) or unvaccinated placebo control. Goats were vaccinated with an inactivated pentavalent FMD vaccine containing serotypes SAT1, SAT2 and SAT3 on day 0 and revaccinated at day 20 post vaccination. Thereafter, thirty-four goats were challenged by tongue inoculation at day 41 post-vaccination using 10^4.57 50% tissue culture infective dose (TCID₅₀) FMDV SAT1 pool. Animals were examined daily and clinical signs were scored. Rectal temperatures were measured daily, with temperatures ≥40 °C defined as fever. Clinical specimens (nasal, oral and rectal swabs) were collected on days 0, 2, 4 and 6 post challenge. Viral shedding was determined using reverse-transcriptase real-time PCR. None of the goats vaccinated with the full cattle dose developed secondary lesions. All vaccinated groups had lower temperatures compared to the unvaccinated controls (P < 0.001). Based on RT-PCR results, goats in the unvaccinated control group shed more virus compared to all groups except for 1/12th (P < 0.05), while goats in the full dose group shed less virus than goats in the 1/12th and the unvaccinated control group (P < 0.05). The results suggest that the 1/3rd (0.67 ml) dose of the vaccine is sufficient to reduce viral shedding after heterologous challenge with a FMDV SAT1 pool.

Keywords: Clinical protection; Dosage; FMD; Goats; Vaccination.

Publication types

Randomized Controlled Trial, Veterinary
Research Support, Non-U.S. Gov't

MeSH terms

Africa, Southern
Animals
Antibodies, Viral
Cattle
Cattle Diseases* / prevention & control
Cattle Diseases* / virology
Female
Foot-and-Mouth Disease Virus / immunology
Foot-and-Mouth Disease* / prevention & control
Goats
Male
Vaccines, Inactivated
Viral Vaccines / administration & dosage
Viral Vaccines / immunology*
Virus Shedding

Substances

Antibodies, Viral
Vaccines, Inactivated
Viral Vaccines