Microbial Genetics and Clonal Dissemination of Salmonella enterica Serotype Javiana Isolated from Human Populations in Arkansas, USA

Salmonella is estimated to cause over a million infections and ~400 deaths annually in the U.S. Salmonella enterica serotype Javiana strains (n = 409) that predominantly originated from the State of Arkansas over a six-year period (2003 to 2008) were studied. This period coincided with a rapid rise in the incidence of S. Javiana infections in the U.S. Children under the age of 10 displayed the highest prevalence of S. Javiana infections, regardless of sex or year of detection. Antimicrobial susceptibility to 15 different antimicrobials was assessed and 92% (n = 375) were resistant to at least one of the antimicrobials. Approximately 89% of the isolates were resistant to sulfisoxazole alone and 3% (n = 11) were resistant to different antimicrobials, including gentamicin, ciprofloxacin or ceftiofur. The pulsed-field gel electrophoresis (PFGE) analyses assessed the genotypic diversity and distribution of S. Javiana strains using XbaI restriction. Nine major clusters were identified and isolates from each group were digested with the restriction enzyme AvrII. Isolates with identical profiles of XbaI and AvrII were found to be disseminated in human populations. These distinct “types” of S. Javiana were persistent in human populations for multiple years. A subset of isolates (n = 19) with unique resistance phenotypes underwent plasmid and incompatibility (Inc) type analyses and the isolates resistant to more than one antimicrobial harbored multiple plasmids (<3 to 165 kb). Furthermore, these strains possessed 14 virulence genes, including pagC, cdtB, and iroN. The whole genome sequences (WGS) of 18 isolates that mostly originated from Arkansas from 2003 to 2011 were compared with isolates collected from different areas in the U.S. in 1999, indicating the perseverance of S. Javiana in disseminating antimicrobial resistance and virulence genes

Immune Cell Reaction Associated with <i>Coenurus cerebralis</i> Infection in Sheep with Particular Reference to ELISA as a Diagnostic Tool

Sturdy is a disease caused by Coenurus cerebralis (C. cerebralis) that typically affects the brain and spinal cord of sheep. So, this study aimed to detect the pathological, hematological and immunological changes caused by C. cerebralis in sheep. On examination, a total of 17 sheep out of 30 sheep (56.7%) from various regions in Egypt were found infected with C. cerebralis from May to August 2019. Each cyst was extracted from the sheep brain; in addition, tissue specimens were taken from the brain tissues for histopathological examination. The hematological profile was analyzed. Enzyme-Linked Immunosorbent Assay’s (ELISA) specificity and sensitivity were evaluated using cystic fluid and protoscolices antigens (Ag). The cell-mediated immunity against the C. cerebralis cyst was also assessed via quantitative Real Time—Polymerase Chain Reaction (qRT-PCR) to show alterations in mRNA expression of the Tumor Necrosis Factor-alpha (TNF-α) and gamma Interferon (IFN-γ) cytokines qRT-PCR. In histopathological sections, cerebral tissue showed an areolar cyst wall with many protoscolices attached to the tissue. The affected part showed prominent necrosis together with inflammatory cells’ aggregation. Hyperplastic proliferation of the ependymal cells was a common finding. The infected sheep exhibited significantly lower total erythrocyte numbers (ER), hemoglobin levels (Hb), packed cell volume (PCV), platelet numbers (PN) and segmented cell numbers compared to apparently healthy sheep. Despite the sensitivity for the indirect ELISA being 100% for both of the Ags (fluid and scolex), the evaluation of ELISA specificity using the two antigen (Ag) preparations showed specificities of 46.2% and 38.5% for fluid and scolex Ag, respectively. Meanwhile accuracy ranged from 76.7% and 73.3% for the fluid and scolex Ags, respectively, that showed the priority was directed to the fluid to be used as an ideal sample type for ELISA. Levels of TNF-α and IFN-γ were significantly elevated in infected sheep compared to non-infected control ones. In conclusion, C. cerebralis is a serious disease infecting sheep in Egypt revealing economic losses. Although this investigation supports preliminary information about the prevalence, pathological and serological characterization of C. cerebralis, further sequencing and phylogenetic analysis is needed to understand better the T. multiceps epidemiology in ruminants and canines in Egypt