Efficacy of Phase I and Phase II Coxiella burnetii Bacterin Vaccines in a Pregnant Ewe Challenge Model

Sarah E. Williams-Macdonald, Mairi Mitchell, David Frew, Javier Palarea-Albaladejo, David Ewing, William T. Golde, David Longbottom, Alasdair J. Nisbet, Morag Livingstone, Clare M. Hamilton, Stephen F. Fitzgerald, Søren Buus, Emil Bach, Annemieke Dinkla, Hendrik-Jan Roest, Ad P. Koets, Tom N. McNeilly*

*Corresponding author af dette arbejde

Publikation: Bidrag til tidsskriftTidsskriftartikelForskningpeer review

9 Citationer (Scopus)
11 Downloads (Pure)

Abstract

The bacterium Coxiella burnetii can cause the disease Q-fever in a wide range of animal hosts. Ruminants, including sheep, are thought to play a pivotal role in the transmission of C. burnetii to humans; however, the only existing livestock vaccine, namely, Coxevac® (Ceva Animal Health Ltd., Libourne, France), a killed bacterin vaccine based on phase I C. burnetii strain Nine-Mile, is only approved for use in goats and cattle. In this study, a pregnant ewe challenge model was used to determine the protective effects of Coxevac® and an experimental bacterin vaccine based on phase II C. burnetii against C. burnetii challenge. Prior to mating, ewes (n = 20 per group) were vaccinated subcutaneously with either Coxevac®, the phase II vaccine, or were unvaccinated. A subset of pregnant ewes (n = 6) from each group was then challenged 151 days later (~100 days of gestation) with 106 infectious mouse doses of C. burnetii, Nine-Mile strain RSA493. Both vaccines provided protection against C. burnetii challenge as measured by reductions in bacterial shedding in faeces, milk and vaginal mucus, and reduced abnormal pregnancies, compared to unvaccinated controls. This work highlights that the phase I vaccine Coxevac® can protect ewes against C. burnetii infection. Furthermore, the phase II vaccine provided comparable levels of protection and may offer a safer and cost-effective alternative to the currently licensed vaccine.

OriginalsprogEngelsk
Artikelnummer511
TidsskriftVaccines
Vol/bind11
Udgave nummer3
Antal sider19
ISSN2076-393X
DOI
StatusUdgivet - 2023

Bibliografisk note

Funding Information:
This research was funded by the Department of Health and Social Care using UK Aid funding and is managed by the BBSRC (BB/R019975/1) The views expressed in this publication are those of the author(s) and not necessarily those of the Department of Health and Social Care. The funding bodies had no role in the study design, data collection and interpretation, or the decision to submit the work for publication.

Publisher Copyright:
© 2023 by the authors.

Citationsformater