A real-time PCR (RT-PCR) assay was designed for the simultaneous identification of and its ciprofloxacin susceptibility status. A SYBR green-based multiplex RT-PCR format was used; it comprised two different forward primers and a common reverse primer to detect single nucleotide polymorphisms (SNPs) in of The primer pairs were evaluated for their sensitivity and specificity using genomic DNA from 254 isolates (82 were ciprofloxacin susceptible and 172 were ciprofloxacin resistant) and 23 non- species isolates. The performance of the primers was validated using genomic DNA from 100 different isolates (46 were ciprofloxacin susceptible and 54 were ciprofloxacin resistant) and 52 non- isolates. The latter panel was revalidated by testing 99 (46 isolates were ciprofloxacin susceptible and 53 isolates were ciprofloxacin resistant) of the isolates and 23 non- isolates. These primers detected and its ciprofloxacin susceptibility status with over 99% sensitivity and specificity for all panels tested. This assay has the potential to be an inexpensive and rapid test for the simultaneous identification of and its ciprofloxacin susceptibility status.

Non-typhoidal Salmonella are a major cause of gastroenteritis worldwide, as well as causing bloodstream infections in sub-Saharan Africa with a high fatality rate. No vaccine is currently available for human use. Current vaccine development strategies are focused on capsular polysaccharides (CPS) present on the surface of non-typhoidal Salmonella. This study aimed to boost the amount of CPS purified from S. Typhimurium for immunization trials. Random mutagenesis with Tn10 transposon increased the production of CPS colanic acid, by 10-fold compared to wildtype. Immunization with colanic acid or colanic acid conjugated to truncated glycoprotein D or inactivated diphtheria toxin did not induce a protective immune response in mice. However, immunization with Generalized Modules for Membrane Antigens (GMMAs) isolated from colanic acid overproducing isolates reduced Salmonella colonization in mice. Our results support the development of a GMMA-CPS-based vaccine against non-typhoidal Salmonella.

Polysaccharides are often the most abundant antigens found on the extracellular surfaces of bacterial cells. These polysaccharides play key roles in interactions with the outside world, and for many bacterial pathogens, they represent what is presented to the human immune system. As a result, many vaccines have been or currently are being developed against carbohydrate antigens. In this review, we explore the diversity of capsular polysaccharides (CPS) in Salmonella and other selected bacterial species and explain the classification and function of CPS as vaccine antigens. Despite many vaccines being developed using carbohydrate antigens, the low immunogenicity and the diversity of infecting strains and serovars present an antigen formulation challenge to manufacturers. Vaccines tend to focus on common serovars or have changing formulations over time, reflecting the trends in human infection, which can be costly and time-consuming. We summarize the approaches to generate carbohydrate-based vaccines for Salmonella, describe vaccines that are in development and emphasize the need for an effective vaccine against non-typhoidal Salmonella strains.

Eleven primer pairs were developed for the identification of Neisseria gonorrhoeae. The sensitivity and specificity of these primers were evaluated by Real Time (RT)-PCR melt curve analyses with DNA from 145 N. gonorrhoeae isolates and 40 other Neisseria or non-Neisseria species. Three primer pairs were further evaluated in a hydrogel-based RT-PCR detection platform, using DNA extracted from 50 N. gonorrhoeae cultures. We observed 100% sensitivity and specificity in the hydrogel assay, confirming its potential as a point-of-care test (POCT) for N. gonorrhoeae diagnosis.

Whole genome sequencing was used to identify mutations in antibiotic resistance-conferring genes, to compare susceptibility predictions with minimum inhibitory concentrations and to ascertain strain types in 99 isolates of Neisseria gonorrhoeae. Genotypes associated with susceptibility as well as MIC creep or emerging resistance were noted. Phylogenomic analysis revealed three distinctive clades and putative gonococcal transmission linkages involving a tetracycline resistant N. gonorrhoeae outbreak and the clonal spread of susceptible isolates in men.