[show abstract][hide abstract] ABSTRACT: Current epidemiological data on the situation of Coxiella (C.) burnetii infections in sheep are missing, making risk assessment and the implementation of counteractive measures difficult. Using the German state of Thuringia as a model example, the estimated sero-, and antigen prevalence of C. burnetii (10% and 25%, respectively) was assessed at flock level in 39/252 randomly selected clinically healthy sheep flocks with more than 100 ewes and unknown abortion rate.
The CHECKIT™ Q-fever Test Kit identified 11 (28%) antibody positive herds, whereas real-time PCR revealed the presence of C. burnetii DNA in 2 (5%) of the flocks. Multiple-locus variable number of tandem repeats analysis of 9 isolates obtained from one flock revealed identical profiles. All isolates contained the plasmid QpH1.
The results demonstrate that C. burnetii is present in clinically inconspicuous sheep flocks and sporadic flare-ups do occur as the notifications to the German animal disease reporting system show. Although C. burnetii infections are not a primary veterinary concern due to the lack of significant clinical impact on animal health (with the exception of goats), the eminent zoonotic risk for humans should not be underestimated. Therefore, strategies combining the interests of public and veterinary public health should include monitoring of flocks, the identification and culling of shedders as well as the administration of protective vaccines.
[show abstract][hide abstract] ABSTRACT: The aim of the study was to examine grazing goats and sheep as specific sentinels for characterization of the tick-borne encephalitis virus (TBEV)-related risk in an area by means of serosurveillance tests in the German federal states Baden-Wuerttemberg, Bavaria, Thuringia, North Rhine-Westphalia, Lower Saxony, Schleswig-Holstein, and Mecklenburg-West Pomerania. A total of 3590 sheep sera and 3793 goat sera was collected in 2003 and 2006-2009 and were examined by ELISA screening and confirmed by serum neutralization test. Considerable differences in seroprevalence were seen between single flocks in districts in Baden-Wuerttemberg, Bavaria, and Thuringia with values between 0 and 43% which confirmed the patchy pattern of TBEV foci that can range in size from very small to large. The here described serological screening may be a helpful tool for an early warning system of a potential TBEV risk. Testing of 1700 ticks by real-time RT-PCR in two districts in Baden-Wuerttemberg revealed only one positive tick, thus illustrating the problems of expensive and time-consuming tick collection.
Ticks and Tick-borne Diseases 02/2012; 3(1):27-37. · 2.35 Impact Factor
[show abstract][hide abstract] ABSTRACT: The epidemiological situation of ovine chlamydial infections in continental Europe, especially Germany is poorly characterised. Using the German state of Thuringia as a model example, the chlamydial sero- and antigen prevalence was estimated in thirty-two randomly selected sheep flocks with an average abortion rate lower than 1%. Seven vaccinated flocks were reviewed separately.
A wide range of samples from 32 flocks were examined. Assumption of a seroprevalence of 10% (CI 95%) at flock level, revealed that 94% of the tested flocks were serologically positive with ongoing infection (i.e. animals with seroconversion) in nearly half (47%) of the flocks. On the basis of an estimated 25% antigen prevalence (CI 95%), PCR and DNA microarray testing, together with sequencing revealed the presence of chlamydiae in 78% of the flocks. The species most frequently found was Chlamydophila (C.) abortus (50%) followed by C. pecorum (47%) and C. psittaci genotype A (25%). Mixed infections occurred in 25% of the tested flocks. Samples obtained from the vaccinated flocks revealed the presence of C. abortus field samples in 4/7 flocks. C. pecorum was isolated from 2/7 flocks and the presence of seroconversion was determined in 3/7 flocks.
The results imply that chlamydial infections occur frequently in German sheep flocks, even in the absence of elevated abortion rates. The fact that C. pecorum and the potentially zoonotic C. psittaci were found alongside the classical abortifacient agent C. abortus, raise questions about the significance of this reservoir for animal and human health and underline the necessity for regular monitoring. Further studies are needed to identify the possible role of C. psittaci infections in sheep.
BMC Veterinary Research 06/2011; 7:29. · 1.86 Impact Factor
[show abstract][hide abstract] ABSTRACT: A goat flock grazing year-round on a meadow in a "TBE non-risk area" in Thuringia, Germany, with a history of only isolated human TBE cases was examined repeatedly for TBE virus-(TBEV)-specific antibodies and TBEV RNA between October 2008 and December 2009. Surprisingly, TBEV specific antibodies were detected in one goat, which had never left this area. To compare the results of a natural contact to TBEV with a defined contact to TBEV, two goats were immunized experimentally. Both animals developed TBEV-specific antibodies, one goat however in a delayed and reduced manner. In addition, 177 ticks were collected from the meadow in May and June 2009, and were examined by real-time RT-PCR. However, noTBEV RNA could be detected. The results suggest that goats can be used as TBEV sentinels in defined areas. To verify this observation further investigations with a large number of animals are recommended.
Berliner und Münchener tierärztliche Wochenschrift 123(11-12):441-5. · 0.89 Impact Factor