Risk factors for an infection with Coxiella burnetii in German sheep flocks

Abstract

In Germany, sheep are the main source of human Q fever epidemics, but data on Coxiella burnetii (C. burnetii) infections and related risk factors in the German sheep population remain scarce. In this cross-sectional study, a standardised interview was conducted across 71 exclusively sheep as well as mixed (sheep and goat) farms to identify animal and herd level risk factors associated with the detection of C. burnetii antibodies or pathogen-specific gene fragments via univariable and multivariable logistic regression analysis. Serum samples and genital swabs from adult males and females of 3367 small ruminants from 71 farms were collected and analysed using ELISA and qPCR, respectively. On animal level, univariable analysis identified young animals (<2 years of age; odds ratio (OR) 0.33; 95% confidence interval (CI) 0.13–0.83) to reduce the risk for seropositivity significantly (p < 0.05). The final multivariable logistic models identified lambing all year-round (OR 3.46/3.65; 95% CI 0.80–15.06/0.41–32.06) and purchases of sheep and goats (OR 13.61/22.99; 95% CI 2.86–64.64/2.21–239.42) as risk factors on herd level for C. burnetii infection detected via ELISA and qPCR, respectively.

Analysis of environmental dust in goat and sheep farms to assess Coxiella burnetii infection in a Q fever endemic area: Geographical distribution, relationship with human cases and genotypes

“…In this sense, Carrié et al (2019) also described a correlation between C. burnetii environmental contamination and the number of reproducing females in the flock. In larger professional flocks, animal trading has also been identified as a risk factor for C. burnetii infection (Wolf et al, 2020), though in this study purchase of animals was not significantly associated with the detection of C. burnetii DNA. As found in this study, contact with other flocks has been described as a contributor for Q fever spread among flocks (Barlozzari et al, 2020;Clark & Soares Magalhaes, 2018;Muema et al, 2017;Obaidat & Kersh, 2017;Rizzo et al, 2016).…”

“…Thus, the implementation of biosecurity measures in farms is one of the main pillars for reducing the spread of the bacteria and to prevent new infections in animals and humans. Control measures include vaccination (Arricau-Bouvery et al, 2005;Astobiza et al, 2011;Bontje et al, 2016), combined with the quick removal of infectious material (placentas, aborted foetuses) (Anderson et al, 2015;Meadows et al, 2015), correct manure management, avoiding the introduction into the flock of susceptible and non-vaccinated animals that could reactivate the infection in the flock (Wolf et al, 2020), as well as cleaning and disinfection of animal premises, among others (Meadows et al, 2015;Mori & Roest, 2018;Plummer et al, 2018).…”

Increasing awareness for tick-borne encephalitis virus using small ruminants as suitable sentinels: Preliminary observations

“…In total, 36 small ruminant flocks (1396 sheep and 323 goats) from 27 districts located in the TBE risk area and 35 small ruminant flocks (1331 sheep and 124 goats) from 22 districts in the non-TBE risk area were involved in the present study. Information on the husbandry system, tick infestation observed by the animal owners and treatment against ectoparasites within the last 12 months was available due to interviews with the farm managers which were conducted for the Q fever study [ 23 ]. These factors were also analysed with regard to TBEV infection in small ruminants.…”

Seroprevalence and Risk Factors of Anaplasma spp. in German Small Ruminant Flocks

“…Moreover, a risk factor analysis was performed to identify potential threats for sheep and goats in Germany to be exposed to Anaplasma species. This risk factor analysis was based on data from a standardised questionnaire which was performed with the sheep farmers [48].…”