Concept of an Active Surveillance System for Q Fever in German Small Ruminants-Conflicts Between Best Practices and Feasibility

Fenja Winter; Clara Schoneberg; Annika Wolf; Benjamin U Bauer; T Louise Prüfer; Silke F Fischer; Ursula Gerdes; Martin Runge; Martin Ganter; Amely Campe

doi:10.3389/fvets.2021.623786

Concept of an Active Surveillance System for Q Fever in German Small Ruminants-Conflicts Between Best Practices and Feasibility

Front Vet Sci. 2021 Feb 10:8:623786. doi: 10.3389/fvets.2021.623786. eCollection 2021.

Authors

Affiliations

¹ Department of Biometry, Epidemiology and Information Processing, WHO Collaborating Centre for Research and Training for Health at the Human-Animal-Environment Interface, University of Veterinary Medicine Hannover Foundation, Hanover, Germany.
² Clinic for Swine, Small Ruminants and Forensic Medicine, University of Veterinary Medicine Hannover Foundation, Hanover, Germany.
³ Lower Saxony State Office for Consumer Protection and Food Safety - Food and Veterinary Institute Braunschweig/Hannover, Hanover, Germany.
⁴ National Consulting Laboratory for Coxiella burnetii, State Health Office Baden-Württemberg, Stuttgart, Germany.
⁵ Animal Disease Fund of Lower Saxony, Public Law Institution, Hanover, Germany.

Abstract

Q fever is a zoonotic disease caused by the bacterium Coxiella burnetii. Inhalation of contaminated dust particles or aerosols originating from animals (esp. small ruminants) is the main source of human infection. Hence, an active early warning system for Q fever in German small ruminant livestock was conceptualized to prevent human infections. First, we describe the best practice for establishing this system before evaluating its feasibility, as the combination of both evokes conflicts. Vaginal swabs from all husbandry systems with a focus on reproductive females should pooled and investigated by PCR to detect C. burnetii-shedding animals. Multistage risk-based sampling shall be carried out at the flock level and within-flock level. At the flock level, all flocks that are at risk to transmit the pathogen to the public must be sampled. At the within-flock level, all primi- and multiparous females after lambing must be tested in order to increase the probability of identifying a positive herd. Sampling should be performed during the main lambing period and before migration in residential areas. Furthermore, individual animals should be tested before migration or exhibition to ensure a negative status. If a flock tests positive in at least one individual sample, then flock-specific preventive measures should be implemented. This approach implies huge financial costs (sample testing, action/control measures). Hence, taking the step to develop more feasible and affordable preventive measures, e.g., vaccinating small ruminant flocks, should replace testing wherever justifiable.

Keywords: Coxiella burnetii; early warning; one health; small ruminants; surveillance system.