Biomedical subjects

S Essbauer

Publications and source records attributed to S Essbauer.

16 recordsLinked to original sources

PubMed2006

A new Puumala hantavirus subtype in rodents associated with an outbreak of Nephropathia epidemica in South-East Germany in 2004.

A micro-epidemic of hantavirus infections occurred in Lower Bavaria, South-East Germany, starting in April 2004. While only three cases were registered from 2001 to 2003, a dramatically increased number of clinically apparent human hantavirus infections (n=38) was observed in 2004, plus seven additional cases by June 2005. To determine the reservoir responsible for the infections, a total of 43 rodents were trapped in Lower Bavaria. Serological and genetic investigations revealed that Puumala virus (PUUV) is dominant in the local population of bank voles. Partial PUUV S segment nucleotide sequences originating from bank voles at four different trapping sites in Lower Bavaria showed a low divergence (up to 3.1%). This is contrasted by a nucleotide sequence divergence of 14-16% to PUUV strains detected in Belgium, France, Slovakia or North-Western Germany. PUUV sequences from bank voles in Lower Bavaria represent a new PUUV subtype which seems to be responsible for the observed increase of human hantavirus infections in 2004-2005.

Animals↗

PubMed2006

Rickettsia spp. in Ixodes ricinus ticks in Bavaria, Germany.

This study aims to provide information on the occurrence of spotted fever rickettsiae in Ixodes ricinus ticks in southern Germany. A total of 2,141 I. ricinus ticks was collected in Bavaria. Pools of 5-10 ticks were studied by a PCR targeting the rickettsial citrate synthase gene gltA. The average prevalence rate was 12% (257 of 2,141). Sequencing data exclusively identified Rickettsia helvetica DNA. Results and other data demonstrate the possible role of R. helvetica in I. ricinus as a source of human infections in southern Germany.

Animals↗

PubMed2004

Avipoxvirus infection in peregrine falcons (Falco peregrinus) from a reintroduction programme in Germany.

Poxvirus infections are common in domestic birds in Germany, but they are rare in birds of prey. Only species of falconidae imported from Arabian or Asian countries have so far tested positive for poxvirus, and, among these, only raptors kept for falconry. As part of a reintroduction programme in the northern county of Mecklenburg-Western Pomerania, which is adjacent to the Baltic Sea, 21 young peregrine falcons were released into the wild; six of them died and one was examined postmortem, its tissues being examined by light and electron microscopy. In addition, an ELISA for fowlpox, pigeonpox and canarypox was applied. No virus could be isolated and propagation in culture failed, but virus particles were detected by electron microscopy in lesions from its skin and tongue.

Animals↗

PubMed2004

[Zoonotic poxviruses].

In the last few years, the mass media and also scientists have been showing an increasing interest in poxviruses. What kind of infections can be found in animals and men today? The following review gives an overview on current taxonomy, properties, epidemiology, and diagnosis of zoonotic poxviruses.

Animals↗

PubMed2004

Unusual presentations of cowpox infection in cats.

Cowpox virus infections are reported typically to cause focal ulcerated, crusted skin lesions, sometimes with mild systemic illness and concurrent oral lesions. Severe systemic illness usually only occurs in young or immunosuppressed individuals. This report describes four cases of cowpox infection in cats which illustrate variations to the usual presentation of the virus. The poxvirus infections were confirmed histopathologically, serologically and by PCR analysis.

Animals↗

PubMed2003

Characterization of aquabirnaviruses from flounder Pseudopleuronectes americanus and mummichog Fundulus heteroclitus in the Chesapeake Bay, Virginia, USA.

Viruses were isolated in cell culture from tissue homogenates of flounder Pseudopleuronectes americanus and mummichog Fundulus heteroclitus in the Chesapeake Bay, Virginia, USA. Neutralization and immunofluorescence tests with aquabirnavirus (West Buxton strain)-specific polyclonal antisera indicated that both viruses were aquabirnaviruses belonging to Serogroup A, the most common aquabirnavirus serogroup in the United States. This was confirmed by RT-PCR, with primers targeting the VP3 and VP2 gene of aquabirnaviruses. The VP2-specific RT-PCR cDNA amplification product was sequenced and deduced amino-acid sequences were compared with known sequences of the type strains of the 9 serotypes of aquabirnavirus Serogroup A. This demonstrated that the viruses from both flounder and mummichog belong to aquabirnavirus Genogroup 1. The flounder isolate exhibited deduced amino acid sequence similarities of 98.1% with the Jasper strain of serotype A9, and 97.7% with the West Buxton strain of serotype A1. The isolate from mummichog exhibited deduced amino acid sequence similarities of 99.1% with the West Buxton strain of Serotype A1 and 94.8% with the Jasper isolate of Serotype A9. Similarities of deduced amino acid sequences ranged from 79.9 to 86.9%, with representatives of the other 7 serotypes. This is the first report of an aquabirnavirus from mummichog F. heteroclitus and only the fifth report of an aquabirnavirus from a flounder species.

Amino Acid Sequence↗

PubMed2003

[Human cowpox/catpox infection. A potentially unrecognized disease].

HISTORY AND ADMISSION FINDINGS: A 36-year-old woman initially noticed a red spot, about pea-sized, with a central pimple over the right eyebrow and a swollen submandibular lymph node. A pressure-sensitive, 4 cm large, node developed out of this small spot, with a central, black, tightly-adhering crust bearing several varioliform vesicles around its edge. In addition to swelling of the right half of the face, the patient had a fever up to 39.5 degrees C, general malaise, nausea and vomiting. Various antibiotics were ineffective. The woman was hospitalized with a diagnosis of facial erysipelas. She owned a cat which had developed a purulent nodule on a forepaw a few days before onset of the patient's disease. LABORATORY TEST: ESR and CRP were moderately elevated, no leukocytosis and blood cultures were sterile. Wound smears showed colonization with Klebsiella pneumoniae and Enterobacter cloacae. DIAGNOSIS, TREATMENT AND COURSE: The patient's general condition improved under initially calculated antibiotic dosages, which was later adapted to the measured resistance. The black-crusted nodes became larger, however, and incision was performed on the 8 th day after hospitalization, under the suspicion of fluctuation. However, no pus was removed, but there was massive inflammatory infiltration of the soft tissue. Examination of samples of skin and part of the crust revealed orthopox virus (cowpox virus). Spontaneous healing followed within 3 weeks, leaving only a small scar. CONCLUSIONS: This was a cowpox virus in the sense of a zoonosis transmitted by the cat. In Germany, now that smallpox has been eradicated, the clinical presentation of infections with the orthopox virus, which are closely related to variola virus, are too little recognized. Atopic and immunocompromised patients are at risk of a cutaneous dissemination with a more severe course of the infectious illness; even a lethal outcome has been reported in Germany.

Adult↗

PubMed2002

Spring viremia of carp (SVC).

Spring viremia of carp (SVC) is an important disease affecting cyprinids, mainly common carp Cyprinus carpio. The disease is widespread in European carp culture, where it causes significant morbidity and mortality. Designated a notifiable disease by the Office International des Epizooties, SVC is caused by a rhabdovirus, spring viremia of carp virus (SVCV). Affected fish show destruction of tissues in the kidney, spleen and liver, leading to hemorrhage, loss of water-salt balance and impairment of immune response. High mortality occurs at water temperatures of 10 to 17 degrees C, typically in spring. At higher temperatures, infected carp develop humoral antibodies that can neutralize the spread of virus and such carp are protected against re-infection by solid immunity. The virus is shed mostly with the feces and urine of clinically infected fish and by carriers. Waterborne transmission is believed to be the primary route of infection, but bloodsucking parasites like leeches and the carp louse may serve as mechanical vectors of SVCV. The genome of SVCV is composed of a single molecule of linear, negative-sense, single-stranded RNA containing 5 genes in the order 3'-NPMGL-5' coding for the viral nucleoprotein, phosphoprotein, matrix protein, glycoprotein, and polymerase, respectively. Polyacrylamide gel electrophoresis of the viral proteins, and sequence homologies between the genes and gene junctions of SVCV and vesicular stomatitis viruses, have led to the placement of the virus as a tentative member of the genus Vesiculovirus in the family Rhabdoviridae. These methods also revealed that SVCV is not related to fish rhabdoviruses of the genus Novirhabdovirus. In vitro replication of SVCV takes place in the cytoplasm of cultured cells of fish, bird and mammalian origin at temperatures of 4 to 31 degrees C, with an optimum of about 20 degrees C. Spring viremia of carp can be diagnosed by clinical signs, isolation of virus in cell culture and molecular methods. Antibodies directed against SVCV react with the homologous virus in serum neutralization, immunofluorescence, immunoperoxidase, or enzyme-linked immunosorbent assays, but they cross-react to various degrees with the pike fry rhabdovirus (PFR), suggesting the 2 viruses are closely related. However, SVCV and PFR can be distinguished by certain serological tests and molecular methods such as the ribonuclease protection assay.

Animals↗

PubMed2002

Recent developments in the epidemiology of virus diseases.

There is continual variation in viral epidemics regarding clinical symptoms, duration and disappearance, and the emergence of new diseases. This can be observed in both human and animal diseases. This evolution of virus diseases is mainly related to three factors: aetiological agent, host and environment. As far as genetic alterations of the virus are concerned, two major mechanisms are involved: mutations such as recombination and reassortment; and selection for resistance or susceptibility. This review focuses on the epidemiology of newly emerged virus diseases in man and animals, such as acquired immunodeficiency syndrome, haemorraghic fevers, bovine spongiform encephalopathy, canine haemorraghic disease and respiratory syndrome in horses.

Animals↗

PubMed2002

The epizootic haematopoietic necrosis virus (Iridoviridae) induces apoptosis in vitro.

The epizootic haematopoietic necrosis virus (EHNV) is an iridovirus causing severe disease in different fish species. We investigated the induction of apoptosis during EHNV infection of the epithelioma carp papulosum (EPC) cell line. Apoptosis reveals several characteristic morphological changes, such as chromatin condensation, nuclear fragmentation, cytoplasm membrane disorientation, or mitochondrial changes. During EHNV infection of EPC cells the occurrence of apoptosis was analysed using a fluorescein-isothiocyanate (FITC) conjugate of annexin-V to detect phosphatidylserines that have changed cytoplasm membrane localization. Annexin-V labelling was obvious 12 h after infection. At 54 h after EHNV infection 39% of the investigated EPC cells exhibited fluorescence. Furthermore, EHNV-infected cells were stained with 4'-6'-diamidino-2-phenylindole (DAPI) to detect pycnotic nuclei. Appearance of DAPI-positive nuclei was found beginning at 18 h after infection. At 54 h after EHNV infection approximately 56% of the EPC cells showed fragmented nuclei. Assays to inhibit a protein kinase-dependent (e.g. double-stranded RNA-dependent protein kinase) apoptosis pathway with 2-aminopurine revealed a reduction of EHNV titres, e.g. titres were reduced 1000-fold in the presence of 100 and 200 mM 2-aminopurine. Apoptosis takes place during iridovirus infection in vitro and it seems to involve the activation of protein kinases.

Animals↗

PubMed2001

Identification and molecular characterization of 18 paramyxoviruses isolated from snakes.

Viral agents from 18 different snake species (families Colubridae, Viperidae, and Crotalidae) showing respiratory symptoms and neuronal disease were identified as paramyxoviruses by typical cytopathogenic effect (CPE), electron microscopy, and hemagglutination inhibition. Detailed molecular characterization of the viruses was performed by partial L- and F-gene-specific reverse transcription polymerase chain reaction (RT-PCR) and sequencing, nucleotide and amino acid sequence alignment, and phylogenetic analysis (PHYLIP). RT-PCR of the partial L-gene (566 nt) was successful for all 18 viruses; amplicons of the partial F-gene (918 nt) could be obtained in 16 cases. F- and L-sequence alignment revealed similarities to Fer de Lance virus (FDLV) ranging from 79 to 88% on a nucleotide basis, and 94 to 99% on an amino acid basis. Phylogenetic analysis of the ophidian paramyxoviruses resulted in three clusters for the L-gene sequence and corresponding clusters for the F-gene sequence, indicating no species specificity. We analyzed the F-protein of the snake paramyxoviruses, which proved to have an identical conserved motif of heptad repeat A and predicted a furin cleavage site. This uniformity distinguishes the snake virus group from the other type species of the subfamily Paramyxovirinae. For further classification, we aligned the sequences of the ophidian paramyxoviruses and members of the Paramyxoviridae, such as Sendai virus (genus Respirovirus), mumps virus (genus Rubulavirus), measles virus (genus Morbillivirus), human respiratory syncytial virus (genus Pneumovirus) (Van Regenmortel and 10 co-authors, 2000) and Hendra virus, which have recently been suggested as type species of the genus Henipavirus (Wang et al., 2000). Maximum sequence similarity was found to the partial L-gene of Sendai virus, with 56% nucleotide and 61% amino acid identity. The FDLV and Sendai virus cluster in the phylogenetic analysis of L- and F-protein regarding the Paramyxovirus type species and Hendra virus and show the closest relationship. Regarding the biological properties, the antigenic distance, and particularly the low homology of available sequences, we propose a new genus for the reptilian paramyxoviruses within the Paramyxoviridae.

Amino Acid Sequence↗

PubMed2001

Comparison of the eIF-2alpha homologous proteins of seven ranaviruses (Iridoviridae).

The alpha-subunit of the eukaryotic initiation factor 2 (eIF-2alpha) is a key component of the translation machinery of the cell. In response to cellular stress such as viral infections, eIF-2alpha is phosphorylated by double-stranded RNA-dependent protein kinase (PKR) leading to the inhibition of cellular protein synthesis. The importance of eIF-2alpha as a regulatory mechanism for protein synthesis is illustrated by the wide variety of strategies employed by viruses to down-regulate PKR. Thus, Vaccinia virus encodes K3L protein, which resembles eIF-2alpha and acts as a pseudo-substrate inhibitor of PKR. Nucleotide sequencing of the genome of epizootic haematopoietic necrosis virus (EHNV), a member of the genus ranavirus of Iridoviridae, has revealed an eIF-2alpha equivalent gene. We have cloned and sequenced eIF-2alpha genes of several iridoviruses of fishes and frogs. The eIF-2alpha open reading frames and deduced proteins of the iridoviruses investigated exhibit a high degree of homology of both nucleotide and amino acid sequences. At the N-terminus, the iridoviral eIF-2alpha shows significant homology to the N-termini of cellular initiation factor 2-alpha of various species, to full-length poxviral eIF-2alpha proteins, and to the S1 domain of ribosomal proteins. Comparison of amino acid sequences of corresponding iridoviral proteins with eIF-2alpha homologous proteins of poxviruses and eukaryotes has revealed a high conservation of motifs. A phylogenetic analysis of eukaryotic eIF-2alpha and poxvirus and iridovirus eIF-2alpha sequences has demonstrated the relationship of these iridoviruses. In order to investigate the role of the eIF-2alpha equivalent, respective genes have been expressed in prokaryotic and eukaryotic (insect, fish and chicken cell) systems. The iridoviral eIF-2alpha protein has a molecular weight of 31 kDa and is cytoplasmic. The cellular and viral protein synthesis of iridoviruses is probably regulated by a mechanism similar to that of Vaccinia virus. Frog-virus 3, the type species of the genus ranavirus of Iridoviridae, has a unique translational efficiency and, moreover, down-regulates the cellular protein synthesis of infected cells.

Amino Acid Sequence↗

PubMed2001

Viruses of lower vertebrates.

Viruses of lower vertebrates recently became a field of interest to the public due to increasing epizootics and economic losses of poikilothermic animals. These were reported worldwide from both wildlife and collections of aquatic poikilothermic animals. Several RNA and DNA viruses infecting fish, amphibians and reptiles have been studied intensively during the last 20 years. Many of these viruses induce diseases resulting in important economic losses of lower vertebrates, especially in fish aquaculture. In addition, some of the DNA viruses seem to be emerging pathogens involved in the worldwide decline in wildlife. Irido-, herpes- and polyomavirus infections may be involved in the reduction in the numbers of endangered amphibian and reptile species. In this context the knowledge of several important RNA viruses such as orthomyxo-, paramyxo-, rhabdo-, retro-, corona-, calici-, toga-, picorna-, noda-, reo- and birnaviruses, and DNA viruses such as parvo-, irido-, herpes-, adeno-, polyoma- and poxviruses, is described in this review.

Amphibians↗

PubMed2001

Occurrence of an invertebrate iridescent-like virus (Iridoviridae) in reptiles.

Viral isolates were obtained in 1998, 1999 and 2000 from the lung, liver and intestine of two bearded dragons (Pogona vitticeps) and a chameleon (Chamaeleo quadricornis) and from the skin of a frill-necked lizard (Chamydosaurus kingii) by using viper heart cells (VH2) at 28 degrees C. Electron microscopic examination of infected VH2 cells revealed the assembly of icosahedral iridovirus-like particles measuring 139 nm (side to side) and 151 nm (apex to apex). Negatively stained virus particles had dimensions of 149 nm (side to side) and 170 nm (apex to apex). Polymerase chain reaction (PCR) amplification of purified viral DNA with primers corresponding to the partial gene encoding the major capsid protein (MCP) of Frog viris-3 (FV-3), the type species of the genus Ranavirus, was unsuccessful. In contrast, primers corresponding to the partial MCP gene of Chilo iridescent virus (CIV; genus Iridovirus) amplified 500-bp products with 97% identity to the nucleotide sequence of CIV and 100% identity to the nucleotide sequence of Gryllus bimaculatus iridescent virus (GbIV), an invertebrate iridescent virus. Virus protein profiles analysed by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and restriction fragment length profiles of purified viral DNA treated with the endonucleases EcoRI, HindIII and HpaII were identical to those of GbIV.

Animals↗

PubMed1998

Comparison of European systemic piscine and amphibian iridoviruses with epizootic haematopoietic necrosis virus and frog virus 3.

Iridovirus-like agents isolated from systemic infected fish (Silurus glanis, SFIR; Ictalurus melas, CFIR I, CFIR II, CFIR III) and from frogs (Rana esculenta, REIR) in Europe, Epizootic Haematopoietic Necrosis Virus (EHNV) isolated in Australia from redfin perch (Perca fluviatilis), and Frog Virus 3 (FV 3) isolated from frogs (Rana pipiens) in the USA were investigated by electron microscopy, polypeptide composition, immunofluorescence, restriction endonuclease digestion, Southern-blot hybridization and polymerase chain reaction (PCR) amplification. All virus isolates proved to be similar in morphology and in size and reacted with EHNV polyclonal antiserum in the immunofluorescence. Whilst DNA restriction profiles of the European piscine isolates cleaved by BamH I were similar, they differed clearly from those of EHNV, REIR and FV 3. Southern-blot analysis of viral BamH I digested DNA using an EHNV DNA probe revealed cross-hybridization with DNA of the investigated iridoviruses. Using a set of primers designed for an open reading frame of the EHNV genome, PCR products of about 250 bp were obtained with the DNA of systemic piscine and amphibian iridoviruses. The data suggest that the systemic piscine and amphibian iridoviruses should be regarded as members of the the genus Ranavirus within the family Iridoviridae.

Animals↗

PubMed1992

Reptilian viruses: adenovirus-like agent isolated from royal python (Python regius).

An adenovirus-like agent was isolated from a moribund royal python (Python regius). The DNA containing virus replicated in IgH2-cells at 30 degrees C forming eosinophilic intranuclear inclusion bodies. The virus proved to be stabile to treatment with chloroform, pH3 und pH 12 but it was labile to heat (56 degrees C). Infected IgH2 cells revealed symmetric hexagonal virus particles measuring 67-79 nm in the nucleus. The isolate shared characteristics with the viruses of the family Adenoviridae.

Adenoviridae↗