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Fraancisella tularensis is the etiologic agent of tularemia and a highly virulent category A biothreat agent (1,2). The most widely distributed subspecies is F. tularensis subsp. holarctica, which is found [...]

Bartonella henselae is a fastidious bacterium associated with infections in humans and cats. The mechanisms involved in the long-term survival of bartonellae despite vigorous host immune responses are poorly understood. Generation of genetic variants is a possible strategy to circumvent the host specific immune responses. The authors have recently demonstrated the coexistence of different genetic variants within the progeny of three primary B. henselae isolates from Berlin by PFGE analysis. Aims of the present study were to determine whether coexistence of different variants is a common feature of B. henselae isolates worldwide and whether the genetic variants originally emerged in vivo. Thirty-four primary isolates from different geographical regions were analysed by subjecting multiple single-colony-derived cultures to PFGE analysis. Up to three genetic variants were detected within 20 (58.8 %) isolates, indicating that most primary isolates display a mosaic-like structure. The close relatedness of the genetic variants within an isolate was confirmed by multi-locus sequence typing. In contrast to the primary isolates, no genetic variants were detected within the progeny of 20 experimental clones generated in vitro from 20 primary isolates, suggesting that the variants were not induced in vitro during the procedure of PFGE analysis. Hence, the genetic variants within a primary isolate most likely originally emerged in vivo. Consideration of the mosaic structure of primary isolates is essential when interpreting typing studies on B. henselae.

A new synthetic procedure involving selective functionalization at the lower rim enables the preparation of the rigidified calix(4)arenes, the 1,2-double bridged calix(4)arenes and the 1,3-monobridged derivatives. In these derivatives, the interconversion between two flattened cone conformations is inhibited and the upper rim is available for further functionalization.

Lyme disease, caused by Borrelia burgdorferi sensu lato (1), is endemic to various areas of Italy (2). The main vector of Lyme disease in Italy is the hard tick (Ixodes [...]

Antimicrobial consumption in veterinary medicine has led to the spread of multi drug-resistance in clinically important bacteria, with the companion animals and their environment involved as emerging reservoirs. While CTX-M-15 and CMY-2 acquired β-lactamases have been widely detected in the bacterial population of companion and breeding animals in European area, DHA-1 enzymes have been rarely reported in veterinary medicine. The aim of the study was to characterize the Escherichia coli associated with mortality of a litter of Bulldog puppies in a breeding kennel located in Pesaro area, Central Italy. The E. coli strains O39 serotype were resistant to 3rd/4th generation cephalosporins, chloramphenicol, aminoglycosides, trimethoprim-sulfamethoxazole, and ciprofloxacin, retaining susceptibility to carbapenems, colistin, fosfomycin, and levofloxacin (by Microscan Autoscan4, EUCAST clinical breakpoints). Pulse field gel electrophoreses (PFGE-XbaI) on five E. coli strains revealed the presence of a single profile. Whole genome sequencing (WGS) analysis revealed a complex resistome, harboring bla TEM–1b, bla CTX–M–15, bla OXA–1, aph(6)-Ib , aac(6′)Ib-cr , aac(3)-Ila , aph(6)-Id , aadA1 , qnrB1 , sul2 , catA1 , catB3 , tetA , and dfrA14 genes located on a 302597 bp IncHI2/HI2A plasmid. Moreover, bla DHA–1, qnrB4 , mph(A) , sul1 , and dfrA17 determinants were carried on an 83,429 bp IncFII plasmid. A bla CMY–2 determinant was carried on a 90,249 bp IncI1 plasmid. Two IncX1 and IncX4 plasmids without antimicrobial resistance genes were also detected. The presence of lpfA , iss , astA , and gad virulence factors was highlighted. This is the first report in Italy on an invasive infection in eight 2-weeks old dogs caused by the same MDR E. coli O39 bla CTX–M–15, bla CMY–2, bla DHA–1, and aac(6′)-Ib-cr positive strain. The above MDR E. coli clone caused the death of the entire litter, despite amoxicillin-clavulanate and enrofloxacin administration. The tank for storage of the water used to prepare the milk-based meal for the litter was the suspected reservoir. [ABSTRACT FROM AUTHOR]

Background: Two main genetic groups (B.12 and B.FTNF002-00) of Francisella tularensis ssp. holarctica are endemic in Europe. The B.FTNF002-00 group proved to be dominant in Western European countries, while strains of the B.12 group were isolated mainly in Northern, Central and Eastern Europe. The clinical course of tularemia in the European brown hare (Lepus europaeus) also shows distinct patterns according to the geographical area. Acute course of the disease is observed in hares in Western European countries, while signs of sub-acute or chronic infection are more frequently detected in the eastern part of the continent. The aim of the present study was to examine whether there is any difference in the virulence of the strains belonging to the B.FTNF002-00 and B.12 genetic clades. Results: Experimental infection of Fischer 344 rats was performed by intra-peritoneal injection of three dilutions of a Hungarian (B.12 genotype) and an Italian (B.FTNF002-00 genotype) F. tularensis ssp. holarctica strain. Moderate difference was observed in the virulence of the two genotypes. Significant differences were observed in total weight loss values and scores of clinical signs between the two genotypes with more rats succumbing to tularemia in groups infected with the B.FTNF002-00 genotype. Conclusions: Results of the experimental infection are consistent with previous clinical observations and pathological studies suggesting that F. tularensis ssp. holarctica genotype B.FTNF002-00 has higher pathogenic potential than the B.12 genotype. [ABSTRACT FROM AUTHOR]

Antimicrobial consumption in veterinary medicine has led to the spread of multi drug-resistance in clinically important bacteria, with the companion animals and their environment involved as emerging reservoirs. While CTX-M-15 and CMY-2 acquired β-lactamases have been widely detected in the bacterial population of companion and breeding animals in European area, DHA-1 enzymes have been rarely reported in veterinary medicine. The aim of the study was to characterize the Escherichia coli associated with mortality of a litter of Bulldog puppies in a breeding kennel located in Pesaro area, Central Italy. The E. coli strains O39 serotype were resistant to 3rd/4th generation cephalosporins, chloramphenicol, aminoglycosides, trimethoprim-sulfamethoxazole, and ciprofloxacin, retaining susceptibility to carbapenems, colistin, fosfomycin, and levofloxacin (by Microscan Autoscan4, EUCAST clinical breakpoints). Pulse field gel electrophoreses (PFGE-XbaI) on five E. coli strains revealed the presence of a single profile. Whole genome sequencing (WGS) analysis revealed a complex resistome, harboring bla TEM-1b , bla CTX-M-15 , bla OXA-1 , aph(6)-Ib , aac(6')Ib-cr , aac(3)-Ila , aph(6)-Id , aadA1 , qnrB1 , sul2 , catA1 , catB3 , tetA , and dfrA14 genes located on a 302597 bp IncHI2/HI2A plasmid. Moreover, bla DHA-1 , qnrB4 , mph(A) , sul1 , and dfrA17 determinants were carried on an 83,429 bp IncFII plasmid. A bla CMY-2 determinant was carried on a 90,249 bp IncI1 plasmid. Two IncX1 and IncX4 plasmids without antimicrobial resistance genes were also detected. The presence of lpfA , iss , astA , and gad virulence factors was highlighted. This is the first report in Italy on an invasive infection in eight 2-weeks old dogs caused by the same MDR E. coli O39 bla CTX-M-15 , bla CMY-2 , bla DHA-1 , and aac(6')-Ib-cr positive strain. The above MDR E. coli clone caused the death of the entire litter, despite amoxicillin-clavulanate and enrofloxacin administration. The tank for storage of the water used to prepare the milk-based meal for the litter was the suspected reservoir., (Copyright © 2020 Mattioni Marchetti, Bitar, Mercato, Nucleo, Marchesini, Mancinelli, Prati, Scarsi, Hrabak, Pagani, Fabbi and Migliavacca.)

Midichloria mitochondrii is an intracellular bacterium found in the hard tick Ixodes ricinus. In this arthropod, M. mitochondrii is observed in the oocytes and in other cells of the ovary, where the symbiont is present in the cell cytoplasm and inside the mitochondria. No studies have so far investigated whether M. mitochondrii is present in the salivary glands of the tick and whether it is transmitted to vertebrates during the tick blood meal. To address the above issues, we developed a recombinant antigen of M. mitochondrii (to screen human sera) and antibodies against this antigen (for the staining of the symbiont). Using these reagents we show that (i) M. mitochondrii is present in the salivary glands of I. ricinus and that (ii) seropositivity against M. mitochondrii is highly prevalent in humans parasitized by I. ricinus (58%), while it is very low in healthy individuals (1·2%). These results provide evidence that M. mitochondrii is released with the tick saliva and raise the possibility that M. mitochondrii is infectious to vertebrates. Besides this, our study indicates that M. mitochondrii should be regarded as a package of antigens inoculated into the human host during the tick bite. This implies that the immunology of the response toward the saliva of I. ricinus is to be reconsidered on the basis of potential effects of M. mitochondrii and poses the basis for the development of novel markers for investigating the exposure of humans and animals to this tick species.

Recently, Italy-particularly the Emilia-Romagna region-was the location of consecutive outbreaks of human diseases caused by the arboviruses chikungunya virus and West Nile virus. The two outbreaks, spread by different species of mosquitoes, were not related, but pointed out the lack of an arboviral surveillance program in this region. Beginning in 2007 entomological surveillance was initiated in the Emilia-Romagna region, and in 2008 the program was improved and extended at Lombardia region. Using CO(2)-baited traps, 65,292 mosquitoes were collected; pooled by date of collection, location, and species; macerated manually; and tested by reverse transcription (RT)-polymerase chain reaction for the presence of alphaviruses, orthobunyaviruses, and flaviviruses. Amplicons were sequenced and employed for identification of viral RNA by basic local alignment search tool search in GenBank. Results of these assays showed (1) the presence of West Nile virus in two pools of Culex pipiens mosquitoes, (2) the presence of RNA of two orthobunyaviruses, Tahyna virus in a pool of Ochlerotatus caspius mosquitoes and Batai virus in a pool of Anopheles maculipennis mosquitoes, and (3) the presence of flavivirus RNAs in pools of Oc. caspius, Aedes albopictus, and Aedes vexans mosquitoes; the sequences of these amplicons were most closely related to flaviviruses that have been detected only in mosquitoes and had no recognized vertebrate host (Aedes flavivirus, Culex flavivirus, and Kamiti River virus).