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G Schares,
M C Langenmayer,
J C Scharr,
L Minke,
P Maksimov,
A Maksimov,
S Schares,
A Bärwald,
W Basso,
J P Dubey, F J Conraths,
N S Gollnick
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ABSTRACT: Diagnosis of acute bovine besnoitiosis is a major diagnostic problem. We developed diagnostic tests to serologically diagnose and differentiate acute and chronic cases of bovine besnoitiosis using affinity purified antigens of Besnoitia besnoiti tachyzoites in immunoblots and in both, a conventional ELISA and an avidity ELISA. Sera of acutely and chronically infected cattle were investigated using these tests. Acutely infected cattle initially recognized an antigen of 74 kDa relative molecular mass, followed by reactions with increasing intensity against 81 and 28 kDa antigens. In addition, faint reactions against antigens with 36, 37, 39 and 42 kDa molecular mass started soon after seroconversion and increased over time. An antigen of 45 kDa molecular mass was transiently recognized early after infection but not or only weakly in the chronic stage. At least two antigens, the 39 and the 42 kDa antigens, seem to be located on the surface of B. besnoiti tachyzoites as determined by biotinylation. Affinity purified antigen was used to establish an APure-BbELISA which showed excellent sensitivity (100%) relative to a serological reference system in naturally, most likely chronically, infected cattle. Specificity was also high (99.8%) as determined in cattle from herds with Neospora caninum-associated abortions. The antibody levels in APure-BbELISA were correlated with the parasite load in the skin or the mucous membrane of the vestibulum vaginae as determined by real-time PCR. In acute cases of bovine besnoitiosis (confirmed by the detection of low avidity IgG in the APure-BbELISA) first specific antibodies were detected by ELISA in all animals except one, at the same time or earlier than in the serological reference system. The detection of parasite DNA in skin by real-time PCR was clearly superior to serological analysis in detecting infected cattle during acute besnoitiosis.
International journal for parasitology 11/2012; · 3.39 Impact Factor
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ABSTRACT: Echinococcus multilocularis is a cestode parasites that frequently occurs in the red fox (Vulpes vulpes), which is the main definitive host in Central Europe. The parasite may infect humans as accidental intermediate hosts and cause alveolar echinococcosis. In the German federal state of Saxony-Anhalt, the occurrence of E. multilocularis in red foxes as a possible source of infection for humans was studied from 1998 to 2010. A significant shift in the geographical centroid of the occurrence of E. multilocularis from a long-known highly endemic area in the southwest of the state towards the north-northeast (3.2 km/year) was found. The overall prevalence in the state increased significantly from 13.6% (1998-2005) to 23.4% (2006-2010). No autochthonous cases of alveolar echinococcosis have been reported to date in Saxony-Anhalt, but this might change in the near future with the spread and increasing biomass of the parasite.
Transboundary and Emerging Diseases 11/2012; · 1.81 Impact Factor
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ABSTRACT: SUMMARY In 2011, a novel orthobunyavirus of the Simbu serogroup, the Schmallenberg virus (SBV), was discovered using a metagenomic approach. SBV caused a large epidemic in Europe in ruminants. As with related viruses such as Akabane virus, it appears to be transmitted by biting midges. Transplacental infection often results in the birth of malformed calves, lambs and goat kids. In more than 5000 farms in Germany, The Netherlands, Belgium, France, UK, Italy, Spain, Luxembourg, Denmark and Switzerland acute infections of adult ruminants or malformed SBV-positive offspring were detected, and high seroprevalences were seen in adult ruminants in the core regions in The Netherlands, Germany and Belgium. The discovery of SBV, the spread of the epidemic, the role of vectors, the impact on livestock, public health issues, SBV diagnosis and measures taken are described in this review. Lessons to be learned from the Schmallenberg virus epidemic and the consequences for future outbreaks are discussed.
Epidemiology and Infection 10/2012; · 2.84 Impact Factor
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ABSTRACT: Six free-ranging European beavers (Castor fiber) from Berlin greater metropolitan area and twelve European wildcats (Felis silvestris silvestris) originating from the German Federal State of Saxony-Anhalt were found dead and their carcasses were submitted for necropsy. Brain and lung samples were analysed for the presence of Toxoplasma gondii DNA. Histo-pathologic analysis of one beaver revealed several cyst-like protozoal structures in parts of the brain. Tissue DNA isolated from all animal samples was analysed by a specific T. gondii-PCR. Two beavers and four wildcats tested T. gondii-positive. DNA of the parasites was further analysed by PCR-RFLP typing using nine markers (nSAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1 and Apico). Only T. gondii type II alleles were detected, except for the Apico locus, where type I alleles were observed in two isolates from beavers and in three from wild cats. The results of this study indicate that type II T. gondii (including type II variant strain) is the most common genotype infecting wildcats and beavers from Germany.
Veterinary Parasitology 09/2012; · 2.58 Impact Factor
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ABSTRACT: SUMMARY Prevalence monitoring of avian influenza in wild bird populations is important to estimate risks for the occurrence of potentially zoonotic and economically disastrous outbreaks of highly pathogenic avian influenza virus (AIV) in poultry worldwide. A targeted, cost-effective monitoring method for AIV in wild birds was developed, which is based on monitoring results for AIV in Germany and information on the distribution and abundance of wild bird species in selected habitat types. Spatial data were combined with virological and outbreak data for the period of 1 January 2006 to 31 December 2010. Using Germany as an example, we identified 11 indicator species. By concentrating monitoring efforts on these species in spatially confined locations, we propose a targeted and more cost-effective risk-based AIV monitoring approach that can be adapted universally for the identification of wild bird indicator species worldwide with the perspective of reducing sample sizes (and costs) without impairing the validity of the results.
Epidemiology and Infection 08/2012; · 2.84 Impact Factor
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ABSTRACT: Data on the genotypes of Toxoplasma gondii circulating in wildlife are scarce. In the present study, foxes and rodents from two Federal States in Central or Eastern Germany were examined for T. gondii infections. Body fluids were collected at necropsy or fluids were obtained from frozen tissues of naturally exposed red foxes (Vulpes vulpes), voles (Microtus arvalis), shrews (Neomys anomalus) and a striped field mouse (Apodemus agrarius) and tested for T. gondii by serology. DNA isolated from tissues of seropositive foxes and all the rodents was examined by PCR. In the German Federal States of Brandenburg and Saxony-Anhalt 152/204 (74.5%) and 149/176 (84.7%) of foxes, respectively, but none of the rodents (0/72) had antibodies to T. gondii. Only 28/152 (18.4%) and 20/149 (13.4%) of seropositive foxes from Brandenburg and Saxony-Anhalt, respectively, but none of the rodents tested PCR-positive for T. gondii. The complete T. gondii genotype could be determined for twelve samples using nine PCR-restriction fragment length polymorphism (PCR-RFLP) markers (newSAG2, SAG3, BTUB, GRA6, c22-8, c29-2, PK1, L358 and Apico). In addition to T. gondii clonal type II (Apico II) and type II (Apico I), type III and T. gondii genotypes showing non-canonical allele patterns were observed in foxes. This suggests that, while T. gondii type II prevails in foxes, other genotypes circulate in wildlife. The population structure of T. gondii in Germany may be more diverse than previously thought.
Veterinary Parasitology 10/2011; 185(2-4):78-85. · 2.58 Impact Factor
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ABSTRACT: This study aimed at isolating and genotyping Toxoplasma gondii from serologically positive free-range chickens from Argentina, and to evaluate the use of sentinel animals during a short time period of exposure to determine environmental contamination with T. gondii oocysts. Two groups of chickens on six farms were compared in this study: (i) young, 2-3 month-old broiler-type chickens reared as sentinel animals on the farms and (ii) adult chickens reared on the same farms for more than one year. Seroconversion rates of 7.0% or 5.7% were observed in sentinel broiler chickens reared for a period of 74 days (January-April 2010) or 88 days (August-November 2010) respectively, as shown by a T. gondii specific immunofluorescent antibody test. Fifty-three percent (17 of 32) of adult chickens were positive and showed higher titres than sentinel animals. Isolation of T. gondii from tissues (brain and heart) of serologically positive chickens was achieved from six of seven free-range adult birds with IFAT titres of 200 and higher. The isolated parasites were analysed by multi-locus polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). The isolated T. gondii showed three different genotypes: two genotypes consisted in atypical allele combinations, and the remaining genotype had exclusively clonal type II alleles. All isolates obtained at a single farm, corresponded to the same genotype. The T. gondii genotypes observed are identical to those described in cats, dogs, chickens and capybaras elsewhere in South America. Two isolates, which showed different allele combinations in PCR-RFLP, were characterized in a mouse virulence assay. While one isolate showed a low virulence a second isolate was of intermediate virulence to mice.
Veterinary Parasitology 09/2011; 184(2-4):116-21. · 2.58 Impact Factor
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P Maksimov,
S Buschtöns,
D C Herrmann, F J Conraths,
K Görlich,
A M Tenter,
J P Dubey,
U Nagel-Kohl,
B Thoms,
L Bötcher,
M Kühne,
G Schares
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ABSTRACT: To obtain estimates for the prevalence of Toxoplasma gondii infection in ducks and geese in Germany, enzyme-linked immunosorbent assays (ELISA) were established based on affinity-purified T. gondii tachyzoite surface antigen 1 (TgSAG1) and used to examine duck and goose sera for T. gondii-specific antibodies. The results of 186 sera from 60 non-infected ducks (Anas platyrhynchos) and 101 sera from 36 non-infected geese (Anser anser) as well as 72 sera from 11 ducks and 89 sera from 12 geese inoculated experimentally with T. gondii tachyzoites (intravenously) or oocysts (orally) and positive in a T. gondii immunofluorescent antibody test (IFAT) were used to select a cut-off value for the TgSAG1-ELISA. Sera obtained by serial bleeding of experimentally inoculated ducks and geese were tested to analyze the time course of anti-TgSAG1 antibodies after inoculation and to assess the sensitivity of the assays in comparison with IFAT. In ducks, IFAT titres and ELISA indices peaked 2 and 5 weeks p.i with tachyzoites, respectively. Only three of six geese inoculated with tachyzoites at the same time as the ducks elicited a low and non-permanent antibody response as detected by the IFAT. In the TgSAG1-ELISA, only a slight increase of the ELISA indices was observed in four of six tachyzoite-inoculated geese. By contrast, inoculation of ducks and geese with oocysts led to an increase in anti-TgSAG1 antibodies within 1 or 2 weeks, which were still detectable at the end of the observation period, i.e. 11 weeks p.i. Inoculation of three ducks and three geese with oocysts of Hammondia hammondi, a protozoon closely related to T. gondii, resulted in a transient seroconversion in ducks and geese as measured by IFAT or TgSAG1-ELISA. Using the newly established TgSAG1-ELISA, sera from naturally exposed ducks and geese sampled in the course of a monitoring program for avian influenza were examined for antibodies to T. gondii; 145/2534 (5.7%) of the ducks and 94/373 (25.2%) of the geese had antibodies against TgSAG1. Seropositive animals were detected on 20 of 61 duck and in 11 of 13 goose farms; the seroprevalences within positive submissions of single farms ranged from 2.2% to 78.6%. Farms keeping ducks or geese exclusively indoors had a significantly lower risk (odds ratio 0.05, 95% confidence interval 0.01-0.3) of harboring serologically positive animals as compared with farms where the animals had access to an enclosure outside the barn.
Veterinary Parasitology 06/2011; 182(2-4):140-9. · 2.58 Impact Factor
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G Pannwitz,
C Freuling,
N Denzin,
U Schaarschmidt,
H Nieper,
A Hlinak,
S Burkhardt,
M Klopries,
J Dedek,
L Hoffmann,
M Kramer,
T Selhorst, F J Conraths,
T Mettenleiter,
T Müller
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ABSTRACT: Between 1985 and 2008, a total of 102,387 wild boar sera originating from Eastern Germany covering an area of 108 589 km2 were tested for the presence of Aujeszky's disease virus (ADV)-specific antibodies. From 1985 until 1991 and from 1992 until 2008, wild boar sera were exclusively investigated using either conventional seroneutralization assays (n=39 621) or commercial gB and full antigen ELISAs (n=62,766), respectively. Spatial-temporal analysis revealed an increasing ADV seroprevalence from 0·4% to 15·9%, on average, during the 24-year observation period that went along with a continuous spread of the infection in a western direction. During 2006 and 2008, 18% of the 66 affected districts had ADV seroprevalences >30%. There was a significant correlation between ADV seroprevalence and the hunting index of population density (HIPD) of wild boar in the entire study area, although this did not hold true for some regions. Seroprevalences did not differ between sexes but were age-dependent. East Germany has been officially free of Aujeszky's disease (pseudorabies) in domestic pigs since 1985. Although a risk for domestic pigs cannot be completely ruled out, experience has shown that ADV in domestic pigs could be eliminated although the virus was present in the wild boar population. Despite increasing ADV seroprevalence in the East German wild boar population no spillover infections from wild boar to domestic pigs have been reported. To further trace ADV infections in the wild boar population in Germany, a nationwide serological monitoring programme should be implemented.
Epidemiology and Infection 02/2011; 140(2):348-58. · 2.84 Impact Factor
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G Schares,
A Maksimov,
W Basso,
G Moré,
J P Dubey,
B Rosenthal,
M Majzoub,
A Rostaher,
J Selmair,
M C Langenmayer,
J C Scharr, F J Conraths,
N S Gollnick
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ABSTRACT: Bovine besnoitiosis, an economically important disease in cattle in some countries of Africa and Asia, is emerging in Europe. The definitive host of Besnoitia besnoiti, the causative agent of bovine besnoitiosis, is unknown and the transmission of the parasite is not completely understood. Sensitive and quantitative DNA detection methods are needed to determine whether serologically positive animals are infectious and to examine the role of vectors (e.g. haematophagous insects) in the transmission of the parasite. To this end, we established two different 5'-nuclease quantitative assays to detect B. besnoiti infection in cattle and to estimate the parasite load in samples (BbRT1 and BbRT2). These PCRs are based on the sequence of the internal transcribed spacer region 1 (ITS-1) of the ribosomal RNA gene. Tests with serial dilutions of B. besnoiti genomic DNA in a buffer containing 100 ng/μl bovine DNA revealed a detection limit of 0.01 pg genomic B. besnoiti DNA. Reliable quantification was possible in samples containing ≥1 pg B. besnoiti genomic DNA with a coefficient of variation of ≤ 2%. To estimate the diagnostic sensitivity of the tests, skin biopsies and scrapings from the mucous membrane of the vestibulum vaginae (vaginal scrapings) were taken from cattle with clinical signs of chronic besnoitiosis. Regardless of the real time PCR assay used, 90.7% (39/43) of these animals were positive in at least one of two samples (skin or vaginal scrapings). Antibody titers, as determined by an immunofluorescent antibody test, and the threshold cycle values of the real time PCR obtained for skin samples and vaginal scrapings, were significantly correlated. The specificity of the PCRs was confirmed using genomic DNA from related parasites, including genomic DNA of Besnoitia spp., Neospora caninum, Toxoplasma gondii, Hammondia hammondi, Hammondia heydorni, Isospora spp., Sarcocystis spp., Eimeria bovis, Cryptosporidium parvum, and Trypanosoma brucei brucei. Since the sequence of the ITS-1 region of B. besnoiti is identical with that of Besnoitia species isolated from donkeys (Besnoitia bennetti), and reindeer (Besnoitia tarandi), both real time PCRs detected also DNA of these parasites. One of the B. besnoiti real time PCRs, BbRT1, but not BbRT2, cross-reacted with Besnoitia darlingi, Besnoitia oryctofelisi, and Besnoitia neotomofelis when large amounts of genomic DNA (10 ng) were used. The other B. besnoiti real time PCR assay (BbRT2) was specific for B. besnoiti, B. bennetti and B. tarandi, but did not react when 10 ng DNA of other related parasite species from the genus Besnoitia or other genera were subjected to analysis.
Veterinary Parasitology 02/2011; 178(3-4):208-16. · 2.58 Impact Factor
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ABSTRACT: The German trade network of pig holdings and related enterprises for the time period of 01 June 2006-31 December 2008 was analyzed. Available data comprised of the entire German trade information with about 121,287 pig premises and their links in the pork production chain (breeders to slaughter houses). During the study period, 330,000 trade connections between premises were recorded. Communities which are large scale structures comprising of premises which are in close trade contact with each other were detected by modularity maximization. Almost 97% of the pig holdings could be assigned to one of nine major communities. Contacts between communities are rare. Trade communities do not only form spatial clusters, but were also associated with specific regions within the territory of Germany. Communities are to some extent separated by 'trade borders', which may impede disease spread. Interestingly, the trade borders often failed to match with administrative borders of the German federal states. This finding is important, because it illustrates the need for new strategies of cross-border disease management strategies.
Preventive Veterinary Medicine 02/2011; 98(2-3):176-81. · 2.05 Impact Factor
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ABSTRACT: Neosporosis is an important cause of reproductive failure in cattle worldwide. Two different abortion patterns associated with Neospora caninum infection have been observed in cattle herds: endemic and epidemic abortion outbreaks. The endemic pattern is characterized by an abortion problem in a herd persisting for several months or years, and is assumed to be caused by reactivation of a chronic infection. In epidemic outbreaks, abortions concentrate within a short period of time, most likely due to a recent point source exposure of naïve animals to N. caninum. The aim of the study was to characterize five N. caninum-associated epidemic abortion outbreaks in Germany by serological and molecular techniques, including a p38-avidity-ELISA and typing of N. caninum in clinical samples by multilocus-microsatellite analysis. DNA extracts from the brain of 18 N. caninum infected fetuses from epidemic abortion outbreaks were characterized using 10 N. caninum-microsatellite markers. Nested-PCR protocols were developed to amplify the marker regions MS1B, MS3, MS5, MS6A, MS6B, MS7, MS12 and MS21 from clinical samples for subsequent analysis by capillary electrophoresis. Microsatellites MS2 and MS10 were analyzed by previously reported sequencing techniques. Most dams which had aborted showed a low-avidity IgG response to the N. caninum p38-antigen, and in three of the five studied herds, the majority of the dams at risk, which had not aborted, had also low-avidity responses suggesting that infection with N. caninum had recently occurred in most animals. A common microsatellite pattern prevailed in all fetuses from each individual epidemic outbreak. This pattern was unique for each herd. Although the number of epidemic abortion outbreaks analyzed was limited, the observation of a common microsatellite pattern, accompanied by a low-avidity IgG response against N. caninum in the dams, supports the hypothesis of a recent infection from a common point source. The genetic diversity of N. caninum observed among these outbreaks may indicate that not a particular N. caninum genotype but the horizontal infection route determines the occurrence of epidemic abortions.
Veterinary Parasitology 10/2010; 173(1-2):24-31. · 2.58 Impact Factor
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G Schares,
W Basso,
M Majzoub,
A Rostaher,
J C Scharr,
M C Langenmayer,
J Selmair,
J P Dubey,
H C Cortes, F J Conraths,
T Haupt,
M Pürro,
A Raeber,
P Buholzer,
N S Gollnick
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ABSTRACT: Bovine besnoitiosis is an economically important disease in cattle caused by the protozoan parasite Besnoitia besnoiti, which occurs endemically in many countries of Africa and Asia and is spreading in Europe. Serological identification of subclinically infected cattle is important to avoid the introduction of infected animals into naive herds. Here we determine the sensitivity and specificity of the PrioCHECK(®) Besnoitia Ab, a serological test recently introduced into the European market. Analytical specificity was examined using sera from animals experimentally infected with parasites related to B. besnoiti (n=27). Three animals experimentally infected with Neospora caninum or Toxoplasma gondii showed inconclusive reactions in the ELISA (percent positivity relative to the positive control [PP] 10% ≤ 20%) while all other sera reacted negative (PP<10%). An estimate of the diagnostic specificity was obtained by analysing field sera from bovine herds without besnoitiosis but with abortion problems associated to N. caninum (n=403). The analysis revealed a specificity of 94.3% or 96.8% depending on the applied cut-off (PP 10% or 20%, respectively). Sensitivity was assessed with sera from 110 animals of a herd in Germany where clinical bovine besnoitiosis was first diagnosed in September 2008. A positive serological reference standard was defined regarding sera from animals as reference positive, if these animals had tested positive in at least two of a panel of three other serological tests (two different B. besnoiti immunoblots and one immunofluorescence antibody test) on both of two sampling dates, November 2008 and April 2009. A diagnostic sensitivity of 91.8% or 75.5% was determined for sera collected in November 2008 and a sensitivity of 82.7% or 50% for sera collected in April 2009 (cut-off PP 10% or PP 20%, respectively). The marked drop in sensitivity from November 2008 to April 2009 was predominantly observed in reference-positive cattle without clinical signs. We conclude that PrioCHECK(®) Besnoitia Ab is a valuable diagnostic tool to detect clinically infected animals. Thus it may be used to support control measures, e.g., for the separation of infected animals from the remaining herd to avoid a further transmission of the infection within the herd.
Veterinary Parasitology 10/2010; 175(1-2):52-9. · 2.58 Impact Factor
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ABSTRACT: In 2008, a cow with marked gross lesions suspicious for bovine tuberculosis (bTB) was identified by meat inspection at home slaughtering in north-western Germany. Epidemiological investigations led to the identification of another 11 affected farms with a total of 135 animals which reacted positive to the skin test. Eight affected farms had been in trade contact with the putative index farm. While the source for the initial introduction remained unknown, it was shown that all isolates tested shared the same molecular characteristics suggesting a common source of infection. The findings demonstrate that bTB can easily be transmitted via animal trade and may remain undetected for years in herds in the absence of tuberculin testing. Hence, we believe that bTB surveillance should not rely only on meat inspection, but on a combination of both meat inspection and intradermal tuberculin testing.
Epidemiology and Infection 04/2010; 139(1):105-12. · 2.84 Impact Factor
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G Schares,
W Basso,
M Majzoub,
A Rostaher,
J C Scharr,
M C Langenmayer,
J Selmair,
J P Dubey,
H C Cortes, F J Conraths,
N S Gollnick
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ABSTRACT: Besnoitia besnoiti, an apicomplexan parasite causes economically important disease in cattle in many countries of Africa and Asia is re-emerging in Europe. Serological identification of infected cattle is important because introduction of these animals into naive herds seems to play a major role in the transmission of the parasite. We report new, simplified immunoblot-based serological tests for the detection of B. besnoiti-specific antibodies. Antigens were used under non-reducing conditions in the immunoblots, because reduction of the antigen with beta-mercaptoethanol diminished the antigenicity in both, tachyzoites and bradyzoites. Ten B. besnoiti tachyzoite and ten bradyzoite antigens of 15-45 kDa molecular weight were recognized by B. besnoiti infected cattle, but not or only weakly detected by cattle infected with related protozoan parasites, Neospora caninum, Toxoplasma gondii, Sarcocystis cruzi, Sarcocystis hominis, or Sarcocystis hirsuta. The sensitivity and specificity of B. besnoiti immunoblots were determined with sera from 62 German cattle with clinically confirmed besnoitiosis and 404 sera from unexposed German cattle including 214 sera from animals with a N. caninum-specific antibody response. Using a new scoring system, the highest specificity (100%) and sensitivity (90%) of the immunoblots were observed when reactivity to at least four of the ten selected tachyzoite or bradyzoite antigens was considered as positive. When a cut-off based on this scoring system was applied to both the tachyzoite- and the bradyzoite-based immunoblots, there was an almost perfect agreement with the indirect fluorescent antibody test with a titre of 200 as the positive cut-off. We identified and partially characterized 10 tachyzoite and 10 bradyzoite B. besnoiti antigens which may help to develop new specific and sensitive serological tests based on individual antigens and in the identification of possible vaccine candidates.
Veterinary Parasitology 03/2010; 171(1-2):32-40. · 2.58 Impact Factor
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T Müller,
B G Klupp,
C Freuling,
B Hoffmann,
M Mojcicz,
I Capua,
V Palfi,
B Toma,
W Lutz,
F Ruiz-Fon,
C Gortárzar,
A Hlinak,
U Schaarschmidt,
K Zimmer, F J Conraths,
E C Hahn,
T C Mettenleiter
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ABSTRACT: Pseudorabies virus (PrV) infections appear to be more widely distributed in the European wild boar (Sus scrofa) population than assumed. In Europe, attempts to isolate and characterize the causative agents have been limited so far. We therefore collected and examined a total of 35 PrV isolates obtained from wild boar or hunting dogs in Germany, France, Spain, Italy, Slovakia and Hungary between 1993 and 2008. Restriction enzyme analysis of genomic DNA using BamHI showed that all isolates, except one, belonged to genogroup I but different subtypes were evident. For further investigations of the phylogenetic relationships, a 732-bp fragment of the glycoprotein C (gC) gene was amplified by PCR. Sequence analysis revealed about 40 variant positions within this fragment. Comparison of the nucleotide sequences supported the separation into a clade containing isolates from North-Rhine Westphalia, Rhineland-Palatinate (Germany), France and Spain (clade B) and an apparently more variable clade comprising isolates from Brandenburg, Baden-Wurttemberg, Saxony, Saxony-Anhalt (Germany), Slovakia, Hungary, Italy and France (clade A).
Epidemiology and Infection 03/2010; 138(11):1590-600. · 2.84 Impact Factor
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T Müller,
A Hlinak,
C Freuling,
R U Mühle,
A Engelhardt,
A Globig,
C Schulze,
E Starick,
U Eggers,
B Sass,
D Wallschläger,
J Teifke,
T Harder, F J Conraths
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ABSTRACT: Between 2003 and 2008, more than 600 white stork (Ciconia ciconia) nestlings in the German federal state of Brandenburg were ringed and examined for influenza A viruses. With the spread of highly pathogenic avian influenza virus (HPAIV) of subtype H5N1 among wild birds in Germany in spring 2006, dead wild birds, including 88 white storks, were tested for infection with HPAIV. Furthermore, fresh fecal samples were examined by RT-PCR to monitor the occurrence of HPAIV in adult storks. While the monitoring of nestlings and adult white storks failed to yield evidence of influenza A virus infections in these birds, two storks found dead in April 2006 in the same location tested positive for HPAIV H5N1. Sequence analysis revealed that the virus isolated from one of the storks belonged to clade 2.2, which was commonly found in wild birds in the north of Germany and other European countries during the epidemic in 2006. Despite these two cases, white storks seemed to serve as neither a vector nor as a reservoir for HPAIV in Germany. The risk of white storks transmitting HPAIV to domestic poultry and humans is low.
Avian Diseases 12/2009; 53(4):578-84. · 1.46 Impact Factor
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ABSTRACT: A total of 18,259 feline faecal samples from cats in Germany were collected and analysed for the presence of Toxoplasma gondii oocysts between June 2007 and December 2008. The proportion of T. gondii-positive samples collected between January and June was significantly lower than between July and December. The age of cats shedding T. gondii oocysts was not significantly different from the age of negative control cats. Forty-six T. gondii-positive samples were genetically characterised using nine PCR-restriction fragment length polymorphism (RFLP) markers which included newSAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1 and Apico. In addition, 22 isolates that had already been partially characterised in a previous study were further typed using PCR-RFLP markers c22-8, c29-2, L358, PK1 and Apico. Genotyping of the 68 isolates revealed that the majority of T. gondii isolates (n=54) had Type II patterns at all loci but displayed a Type I pattern at the Apico locus. Three isolates displayed Type II patterns at all loci, including the Apico locus. In addition, we detected one isolate with clonal Type III patterns at all loci and three isolates with atypical and mixed genotypes. Seven isolates could not be fully genotyped. One of those isolates displayed alleles of both Types I and II at the Apico locus. To our knowledge this is the first description of the presence of T. gondii genotypes different from the clonal Types I, II and III in the faeces of naturally infected cats.
International journal for parasitology 09/2009; 40(3):285-92. · 3.39 Impact Factor
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ABSTRACT: Besnoitia besnoiti was in vitro isolated during the first recorded outbreak of bovine besnoitiosis in Germany. Molecular characterization of the new isolate, named Bb-GER1, revealed almost 100% identity with other B. besnoiti isolates obtained in Portugal, Spain, Israel or South Africa, when partial sequences of the 18S ribosomal RNA gene, of the internal transcribed spacer 1 and of the 5.8S RNA gene were compared. Cystozoites obtained from skin tissue of one bull were infectious for gamma-interferon knockout (GKO) mice by intraperitoneal (ip) inoculation. Tachyzoites were detected in the peritoneal cavity, spleen, liver and lung of the mice 5 days post-infection. The parasite could be maintained in GKO mice by ip inoculation for at least 5 passages. Peritoneal washings containing tachyzoites were obtained from infected mice and used to infect five cell lines (Vero, MARC-145, NA42/13, BHK(21), KH-R). The best growth of tachyzoites was observed in BHK(21) cells, but replication occurred to a smaller extent also in MARC-145, NA42/13 and KH-R cells. Subsequent comparative analyses revealed that after direct infection of these cell lines with cystozoites derived from bovine skin, the growth was best in NA42/13 cells. Considerable replication was also observed in the BHK(21) and KH-R cell lines. Our observations on the growth characteristics of Bb-GER1 partially contrast those for other isolates. The preferential growth in particular cell lines may be characteristic for particular B. besnoiti isolates. A potential association between growth properties and differences in virulence remains to be established. This is the first in vitro isolation of B. besnoiti from cattle in Germany.
Veterinary Parasitology 06/2009; 163(4):315-22. · 2.58 Impact Factor
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ABSTRACT: After massive epidemics of bluetongue disease in 2006 and 2007, Germany has started a compulsory vaccination program against bluetongue virus serotype 8 (BTV-8). Since the available vaccines had not yet been registered and only limited data were available on their performance, a safety study was conducted with three different inactivated monovalent vaccines under consideration for use in Germany. A total of 1007 sheep and 893 cattle were vaccinated and subsequently compared with 638 control animals (324 sheep and 314 cattle). During the study, all animals remained in good health condition. After the initial immunisation, only local swellings were observed in a small number of animals. Following revaccination, several sheep developed more distinct local reactions and a temporary rise in body temperature. Severe systemic reactions were not detected in any of the study groups. Among cattle, neither fever, nor a decrease in milk production and only temporary low-grade local reactions were observed. Overall, our results demonstrate a high level of safety of all vaccines tested.
Vaccine 06/2009; 27(31):4118-26. · 3.77 Impact Factor
