Bartonella vinsonii sub. arupensis infection in animals of veterinary importance, ticks and biopsy samples

Testing for vector-borne pathogens in livestock is largely reliant upon blood and tissue. The role of biopsy samples remains poorly explored for detecting tick-borne bacteria in animals. In a 2-year survey, animals of veterinary importance from farms throughout the Northern part of Greece were routinely checked for the presence of biopsy samples. Where detected, either a portion or biopsy was collected together with whole blood samples and any ticks at the site of the biopsy sample. Molecular testing was carried out by real-time PCR targeting the ITS gene of Bartonella species. A total 68 samples [28 blood samples, 28 biopsy samples and 12 ticks (9 Rhipicephalus bursa and 3 R. turanicus)] were collected from goats (64 samples) and bovine (4 samples). Eight (11.8%) of the 68 samples were positive for Bartonella species. Of the biopsy sample and whole blood samples, four (14.3%) of each type were positive for Bartonella species. None of the ticks was tested positive for Bartonella species. All pairs of positive biopsy samples/whole blood samples originated from the same animals. Positive samples were identified as B. vinsonii sub. arupensis. Although many more samples from a much wider spectrum of animal species is required before concluding upon the merit of biopsy samples on the study of tick-borne diseases, the significance of our finding warrants further study, both for clinical consequences in small ruminants and for those humans farming infected animals

Evaluation and prioritization of biological risk in Ready-To-Eat (RTE) meat products through mathematical modelling

[SPA] La producción moderna de alimentos ha reducido el coste y ha aumentado la variedad de alimentos disponibles, pero esta centralización del suministro de alimentos presenta una oportunidad para que los patógenos y toxinas transmitidos por los alimentos infecten y envenenen a un gran número de consumidores. El modelado es una herramienta clave para garantizar la seguridad de los alimentos producidos a partir de materias primas para el consumidor final. La hipótesis inicial es que es posible mejorar la seguridad de los productos cárnicos listos para comer (LPC) mediante la evaluación/priorización de riesgos biológicos. La clasificación de riesgos de los riesgos para la salud de los alimentos y la seguridad alimentaria y nutricional se reconoce generalmente como el punto de partida para el establecimiento de prioridades basadas en el riesgo y la asignación de recursos, ya que permite a los encargados de formular políticas asignar sus recursos al problema de salud pública más importante. El resultado de esta tesis será una herramienta sólida de gestión de la inocuidad de los alimentos que puede ser implementada por todos los interesados, como las agencias de protección al consumidor (EFSA, ECDC) y la industria. [ENG] Modern food production has reduced the cost and increased the variety of food available, but this centralisation of the food supply presents an opportunity for foodborne pathogens and toxins to infect and poison large numbers of consumers. Modelling is a key tool to ensure the safety of food produced from raw material to the final consumer. The starting hypothesis is that it is possible to improve the safety of Ready To Eat (RTE) meat products by evaluation / prioritization of biological risks. Risk ranking of feed/food safety and nutritional related health risks is generally recognised as the starting point for risk-based priority setting and resource allocation, as it permits policymakers to allocate their resources on the most significant public health problem. The outcome of the thesis will be a robust tool for food safety management that can be implemented by all stakeholders, such as agencies related to consumer protection (EFSA, ECDC) and industry.Leonidas Georgalis is grateful to the MINECO for awarding him a pre−doctoral grant, through Project AGL2017-86840-C2-1-R. To EFSA for awarding him an EU FORA fellowship, 2019-2020

Electrochemical Antigenic Sensor for the Diagnosis of Chronic Q Fever

In this work, we report the development of an impedimetric biosensor for the direct, quick, and easy diagnosis of chronic Q fever. The biosensor is based on highly sensitive antigens that can selectively recognize antibodies against Coxiella burnetii. The biosensor is based on the immobilization of antigens onto a gold electrode using the EDC/NHS immobilization methodology. The detection is performed by impedance spectroscopy that monitors specific frequencies which provide the maximum sensitivity for the biosensor. Q fever antibodies that are present in the sera of patients interact selectively with the biosensor antigens, thereby altering the impedance of the biosensor surfaceand generating a large impedance change within a few seconds. The biosensor allows for the specific serological detection of chronic Q fever, while the developed system can also be modified for the detection of other biomarkers, such as the ones against acute Q fever

Serological survey of Chlamydia abortus in Greek dairy sheep flocks

Chlamydiosis due to Chlamydia abortus is one of the most common causes of abortion in small ruminant flocks worldwide. Although the causative agent is zoonotic, chlamydiosis is not a reportable disease. There is lack of recent data concerning sheep chlamydiosis in Greece.In the current study, a serological investigation for Chlamydia abortus was conducted. Blood samples from 26 randomly selected sheep flocks not vaccinated against chlamydiosis were collected. From each flock, 15 to 20 blood samples were taken from adult female sheep. In total 464 blood samples were examined. One hundred and six samples were positive (22.8%), while 24 samples (5.24%) were doubtful.  Moreover, at farm level, in 18 out of the total number of 26 farms, at least one positive animal was detected (69.2%).Chlamydiosis is considered a highly likely cause of sheep abortion in Greece. Therefore, vaccination of the sheep flocks is strongly recommended for the prevention and control of the disease.

Antibodies against Coxiella burnetii and pregnancy outcome during the 2007-2008 Q fever outbreaks in the Netherlands

<p>Abstract</p> <p>Background</p> <p>Q fever has become a major public health problem in the Netherlands. Infection with <it>Coxiella burnetii </it>(Q fever) during pregnancy has resulted in adverse pregnancy outcome in the majority of reported cases. Therefore, we aimed to quantify this risk by examining the earliest periods corresponding to the epidemic in the Netherlands.</p> <p>Methods</p> <p>Serum samples that had been collected from the area of highest incidence by an existing national prenatal screening programme and data from the Netherlands Perinatal Registry (PRN) on diagnosis and outcome were used. We performed indirect immunofluorescence assay to detect the presence of IgM and IgG antibodies against <it>C. burnetii </it>in the samples. The serological results were analyzed to determine statistical association with recorded pregnancy outcome.</p> <p>Results</p> <p>Evaluation of serological results for 1174 women in the PRN indicated that the presence of IgM and IgG antibodies against phase II of <it>C. burnetii </it>was not significantly associated with preterm delivery, low birth weight, or several other outcome measures.</p> <p>Conclusion</p> <p>The present population-based study showed no evidence of adverse pregnancy outcome among women who had antibodies to <it>C. burnetii </it>during early pregnancy.</p

Quantitative Proteome Profiling of C. burnetii under Tetracycline Stress Conditions

The recommended antibiotic regimen against Coxiella burnetii, the etiological agent of Q fever, is based on a semi-synthetic, second-generation tetracycline, doxycycline. Here, we report on the comparison of the proteomes of a C. burnetii reference strain either cultured under control conditions or under tetracycline stress conditions. Using the MS-driven combined fractional diagonal chromatography proteomics technique, out of the 531 proteins identified, 5 and 19 proteins were found significantly up- and down-regulated respectively, under tetracycline stress. Although the predicted cellular functions of these regulated proteins did not point to known tetracycline resistance mechanisms, our data clearly reveal the plasticity of the proteome of C. burnetii to battle tetracycline stress. Finally, we raise several plausible hypotheses that could further lead to more focused experiments on studying tetracycline resistance in C. burnetii and thus reduced treatment failures of Q fever

Variations of Plasmid Content in Rickettsia felis

Background: Since its first detection, characterization of R. felis has been a matter of debate, mostly due to the contamination of an initial R. felis culture by R. typhi. However, the first stable culture of R. felis allowed its precise phenotypic and genotypic characterization, and demonstrated that this species belonged to the spotted fever group rickettsiae. Later, its genome sequence revealed the presence of two forms of the same plasmid, physically confirmed by biological data. In a recent article, Gillespie et al. ( PLoS One. 2007; 2( 3): e266.) used a bioinformatic approach to refute the presence of the second plasmid form, and proposed the creation of a specific phylogenetic group for R. felis. Methodology/ Principal Findings: In the present report, we, and five independent international laboratories confirmed unambiguously by PCR the presence of two plasmid forms in R. felis strain URRWXCal(2)(T), but observed that the plasmid content of this species, from none to 2 plasmid forms, may depend on the culture passage history of the studied strain. We also demonstrated that R. felis does not cultivate in Vero cells at 37 degrees C but generates plaques at 30 degrees C. Finally, using a phylogenetic study based on 667 concatenated core genes, we demonstrated the position of R. felis within the spotted fever group. Significance: We demonstrated that R. felis, which unambiguously belongs to the spotted fever group rickettsiae, may contain up to two plasmid forms but this plasmid content is unstable

Rickettsia felis, an emerging flea-transmitted human pathogen

Rickettsia felis was first recognised two decades ago and has now been described as endemic to all continents except Antarctica. The rickettsiosis caused by R. felis is known as flea-borne spotted fever or cat-flea typhus. The large number of arthropod species found to harbour R. felis and that may act as potential vectors support the view that it is a pan-global microbe. The main arthropod reservoir and vector is the cat flea, Ctenocephalides felis, yet more than 20 other species of fleas, ticks, and mites species have been reported to harbour R. felis. Few bacterial pathogens of humans have been found associated with such a diverse range of invertebrates. With the projected increase in global temperature over the next century, there is concern that changes to the ecology and distribution of R. felis vectors may adversely impact public health

Rickettsia typhi IN RODENTS AND R. felis IN FLEAS IN YUCATÁN AS A POSSIBLE CAUSAL AGENT OF UNDEFINED FEBRILE CASES

Rickettsia typhi is the causal agent of murine typhus; a worldwide zoonotic and vector-borne infectious disease, commonly associated with the presence of domestic and wild rodents. Human cases of murine typhus in the state of Yucatán are frequent. However, there is no evidence of the presence of Rickettsia typhi in mammals or vectors in Yucatán. The presence of Rickettsia in rodents and their ectoparasites was evaluated in a small municipality of Yucatán using the conventional polymerase chain reaction technique and sequencing. The study only identified the presence of Rickettsia typhi in blood samples obtained from Rattus rattus and it reported, for the first time, the presence of R. felis in the flea Polygenis odiosus collected from Ototylomys phyllotis rodent. Additionally, Rickettsia felis was detected in the ectoparasite Ctenocephalides felis fleas parasitizing the wild rodent Peromyscus yucatanicus. This study’s results contributed to a better knowledge of Rickettsia epidemiology in Yucatán