Characterisation of a Staphylococcus aureus Isolate Carrying Phage-Borne Enterotoxin E from a European Badger (Meles meles)

Staphylococcus (S.) aureus colonizes up to 30% of all humans and can occasionally cause serious infections. It is not restricted to humans as it can also often be found in livestock and wildlife. Recent studies have shown that wildlife strains of S. aureus usually belong to other clonal complexes than human strains and that they might differ significantly with regard to the prevalence of genes encoding antimicrobial resistance properties and virulence factors. Here, we describe a strain of S. aureus isolated from a European badger (Meles meles). For molecular characterisation, DNA microarray-based technology was combined with various next-generation sequencing (NGS) methods. Bacteriophages from this isolate were induced with Mitomycin C and characterized in detail by transmission electron microscopy (TEM) and NGS. The S. aureus isolate belonged to ST425 and had a novel spa repeat sequence (t20845). It did not carry any resistance genes. The uncommon enterotoxin gene see was detected in one of its three temperate bacteriophages. It was possible to demonstrate the induction of all three prophages, although only one of them was expected to be capable of excision based on its carriage of the excisionase gene xis. All three bacteriophages belonged to the family Siphoviridae. Minor differences in size and shape of their heads were noted in TEM images. The results highlight the ability of S. aureus to colonize or infect different host species successfully, which can be attributed to a variety of virulence factors on mobile genetic elements, such as bacteriophages. As shown in the strain described herein, temperate bacteriophages not only contribute to the fitness of their staphylococcal host by transferring virulence factors, but also increase mobility among themselves by sharing genes for excision and mobilization with other prophages.

Identification, differentiation and antibiotic susceptibility of Gallibacterium isolates from diseased poultry

Background

Gallibacterium anatis is an opportunistic pathogen of intensively reared poultry causing oophoritis, salpingitis, peritonitis and enteritis. Gallibacterium anatis infection often remains undiagnosed. Recently multi-drug resistant isolates have been described.

Methods

A newly developed PCR restriction fragment length polymorphism assay targeting the 16S rRNA gene was used to identify and differentiate Gallibacterium isolates from chicken, turkey and partridge samples originating from 18 different geographical locations in Thuringia, Germany. Antimicrobial susceptibility to 19 compounds of different classes was assessed.

Results

Nineteen Gallibacterium isolates were investigated. In 9 birds (47.4%) Gallibacterium species were isolated exclusively while in 10 birds (52.6%) other bacterial or viral agents could be detected in addition. In one chicken a mixed infection of Gallibacterium anatis and Gallibacterium genomospecies was identified. All isolates were susceptible to apramycin, florfenicol and neomycin and resistant to clindamycin, sulfathiazole and penicillin. Resistance to sulfamethoxim, spectinomycin, tylosin and oxytetracycline was observed in 93.3%, 93.3%, 86.7% and 80.0% of the field strains, respectively.

Conclusions

The PCR-RFLP assay allows specific detection and differentiation of Gallibacterium spp. from poultry. Antimicrobial resistance of Gallibacterium spp. is highly significant in Thuringian field isolates.

German Francisella tularensis isolates from European brown hares (Lepus europaeus) reveal genetic and phenotypic diversity

BACKGROUND

Tularemia is a zoonotic disease caused by Francisella tularensis that has been found in many different vertebrates. In Germany most human infections are caused by contact with infected European brown hares (Lepus europaeus). The aim of this study was to elucidate the epidemiology of tularemia in hares using phenotypic and genotypic characteristics of F. tularensis.

RESULTS

Cultivation of F. tularensis subsp. holarctica bacteria from organ material was successful in 31 of 52 hares that had a positive PCR result targeting the Ft-M19 locus. 17 isolates were sensitive to erythromycin and 14 were resistant. Analysis of VNTR loci (Ft-M3, Ft-M6 and Ft-M24), INDELs (Ftind33, Ftind38, Ftind49, RD23) and SNPs (B.17, B.18, B.19, and B.20) was shown to be useful to investigate the genetic relatedness of Francisella strains in this set of strains. The 14 erythromycin resistant isolates were assigned to clade B.I, and 16 erythromycin sensitive isolates to clade B.IV and one isolate was found to belong to clade B.II. MALDI-TOF mass spectrometry (MS) was useful to discriminate strains to the subspecies level.

CONCLUSIONS

F. tularensis seems to be a re-emerging pathogen in Germany. The pathogen can easily be identified using PCR assays. Isolates can also be identified within one hour using MALDI-TOF MS in laboratories where specific PCR assays are not established. Further analysis of strains requires genotyping tools. The results from this study indicate a geographical segregation of the phylogenetic clade B.I and B.IV, where B.I strains localize primarily within eastern Germany and B.IV strains within western Germany. This phylogeographical pattern coincides with the distribution of biovar I (erythromycin sensitive) and biovar II (erythromycin resistance) strains. When time and costs are limiting parameters small numbers of isolates can be analysed using PCR assays combined with DNA sequencing with a focus on genetic loci that are most likely discriminatory among strains found in a specific area. In perspective, whole genome data will have to be investigated especially when terrorist attack strains need to be tracked to their genetic and geographical sources.

Detection of Francisella tularensis subsp. holarctica in a European brown hare (Lepus europaeus) in Thuringia, Germany

The isolation of Francisella tularensis subsp. holarctica biovar II (strain 06T0001) from a European brown hare (Lepus europaeus) from Thuringia, Germany, is described for the first time. Identification of the microorganism was carried out by phenotypic characterisation, partial sequencing of the 16S rRNA gene and specific PCR using the primers TUL4-435/TUL4-863 and FtC1/FtC4. The epidemiology of tularemia in Germany is discussed and a risk assessment for humans is made.

Ausbruch der Koi-Herpesvirusinfektion in einer großen Karpfenteichwirtschaft in Nordthüringen

Gegenstand: Bericht über eine Koi-Herpesvirusinfektion. Material und Methoden: Eine bedeutende Koi-Herpesvirusinfektion, die erstmalig in Thüringen auftrat, wird in ihrem Verlauf beschrieben. Der Nachweis des Virus erfolgte mittels PCR-Untersuchung. Ergebnisse: Die Infektion führte zu schwersten Krankheitsverläufen mit Massenverlusten bei Karpfen aller Altersklassen, wobei es in den K1-Beständen zu Totalverlusten kam. Die Krankheit war ausschließlich auf Karpfen beschränkt. Die erkrankten Bestände wurden tierschutzgerecht getötet und entsorgt. Dem schlossen sich fischereiliche sowie teichhygienische Maßnahmen an. Die direkten Schäden durch Fischverluste und Entsorgungskosten beliefen sich auf 310 000 €. Die Desinfektionskosten betrugen 19 000 €. Die epidemiologischen Erhebungen ergaben, dass die Erkrankung durch den Zukauf latent verseuchter Satzfische eingeschleppt wurde. Die Untersuchungsergebnisse im Jahr 2005 geben Anlass zu der Annahme, dass die Sanierung der Teichwirtschaft von der Krankheit erfolgreich verlief. Klinische Relevanz: Da keine Behandlungen bzw. Immunisierungen möglich sind, bleibt als wichtigste präventive Maßnahme der Zukauf von Satzfischen aus klinisch unverdächtigen, virologisch kontrollierten Betrieben bestehen.

[Evidence of Cryptococcus neoformans in domestic and sports pigeons in Thyringia]

19 strains of Cryptococcus neoformans var. neoformans were isolated from 17 (= 40.5%) of 42 investigated pigeon breeder flocks in Thuringia.

[Mycoses in fish]

Over 4 years 1.241 fish were examined mycologically. In 182 (14.7%) of them positive results were obtained. Most of the isolates belonged to the following genera: Cladosporium, Saprolegnia, Candida and Penicillium. Fungal infections were correlated with findings of Saprolegnia, Branchiomyces, Pythium, Ichtyophonus and sometimes Cladosporium. Most fungal isolates were etiologically irrelevant for diseases or death.

[Clinical, diagnostic laboratory and therapeutic studies of mastitis in a large sheep breeding flock]

During two lambing seasons, 6500 ewes of a large sheep breeding unit were investigated. Within this period, 467 ewes suffered from mastitis. The morbidity was 3.8% and the lethality 4.7%. In 84% of the investigated animals udder-pathogenic bacteria were detected. Mostly, Pasteurella haemolytica and Staphylococcus aureus were isolated as agents of ovine mastitis. Before and during the antibiotic therapy the clinical symptoms (general condition, temperature, milk appearance, consistency of the udder tissue) were recorded. The combined antibiotic therapy, which consisted of parenteral and local intracisternal applications, was mostly satisfactory concerning recovery from mastitis and survival of the ewes. Only 17 ewes died from mastitis; most deaths caused by Staphylococcus aureus.

[Mycoplasma bovis-free breeding of cattle]

On a cattle farm latently infected by M. bovis, field studies aiming at the formation of a mycoplasma free herd, were carried out with a group of newborn female calves. These calves were strictly separated from their dams and any other cattle immediately after parturition. Intensive investigations for mycoplasmas were made over 30 months (mycoplasma isolation from nasal swabs, antibody detection by means of indirect hemagglutination test and ELISA technique). M. bovis could never be isolated from the samples. Also, there were no antibodies to M. bovis. In some animals antibody titers to M. bovis occurred after having contact with cattle infected with M. bovis. The results demonstrate a practicable way to establish cattle herds free from M. bovis infection.

[Listeria abortions in cattle--bacteriology, serology and epizootiology]

Listeria abortions were established in foetuses of cattle in 1.2% of the cases investigated in the Erfurt region and 1.8% in the Cottbus region from 1984 to 1989. The isolated strains have been found biochemically to be L. monocytogenes. The serological discrimination revealed a majority of serovar O I, II. Typing by phages of a part of isolated strains showed a clear predominance of code number 000 124 by the 1/2 a isolate (corresponds to O I, II). This type of phages seems to have a epizootiological importance. Listeria abortions were found in (a lot of 63) flocks in the Erfurt region. Nevertheless there were almost no accumulations of listeria abortions and listeria encephalitis at the same time in the analysed flocks.

Experimental infection of the udder of ewes due to Mycoplasma bovis

Twelve freshly lactating ewes were experimentally infected with 2 Mycoplasma (M.) bovis strains via the teat canal in the left udder. The M. bovis infection produced a febrile clinical mastitis in all infected animals. M. bovis could be re-isolated regularly from the experimentally infected udder halves and the infection spread to the other halves. Some contact animals and 4 suckling lambs became naturally infected. Antibody titres were detected by means of the indirect hemagglutination test in blood sera 2 to 3 weeks post infectionem. The pathological lesions were similar to those of the M. bovis mastitis of cows. By the end of the trial the ewes had recovered from the clinical mastitis.

[Chlamydia as the cause of abortions in horses]

Between 1982 and 1989 59 equine fetuses were investigated for chlamydiae using animal experiments and embryonated eggs. Chlamydiae were isolated from 16 fetuses (27.1%) originating from 8 studs. The macroscopical lesions of the fetal organs were characterized by extensive haemorrhages. The histological picture shows severe lesions of the blood vessels of different organs. In 6 studs in which chlamydiae had been isolated, blood sera of clinically healthy and pregnant mares were investigated for antibodies during 1989 and 1990. Antibody titres between 1:10++ and 1:40 were detected by using complement fixation test in sera of mares of 4 studs.

[The functional and hygienic evaluation of a thermal exchange storage apparatus for recovering warmth from outgoing stable air]

By means of a thermo exchange apparatus it is possible to recover 70 to 80 percent of warmth of the stable air for heating. Thus much energy for climatizing can be saved. Alternating directions of to and from air streams may cause re-influx of germs, dependent on percentage of dust. This risk can be minimized by using an apparatus each for relatively small units separately.