Sixty-two multidrug resistant Salmonella enterica serovar Typhimurium strains isolated from 255 clinical strains collected in Southern Italy in 2006–2008 were characterised for antimicrobial resistance genes, pulsotype, and phage type.Most strains (83.9%) were resistant to ampicillin, chloramphenicol, streptomycin, sulfamethoxazole, and tetracycline (resistance pattern ACSSuT) encoded in 88.5% by the PSE-1, floR, aadA2, sul1, and tet(G) gene cluster harboured by the Salmonella Genomic Island (SGI1). In 11.5% of strains, the resistance was encoded by the InH-like integron (OXA-30-aadA1) and the catA1, sul1, and tet(B) genes. STYMXB.0061 (75%) and DT120 (84.6%) were the prevalent pulsotype and phage type identified in these strains, respectively. Five other resistance patterns were also found either in single or in a low number of isolates with TEM, dfrA12, strAB, sul2, tet(A), and tet(B) encoding for the associated ampicillin, trimethoprim, streptomycin, sulfamethoxazole, and tetracycline resistances, respectively. The pandemic DT104 clone, resistance pattern ACSSuT encoded by SGI1, has largely been identified in Italy since 1992, while strains DT120, resistance pattern ACSSuT (encoded by SGI1), have never been previously reported in Italy. In Europe, clinical S. Typhimurium strains DT120 have mainly been reported from sporadic outbreaks linked to the consumption of pork products.However, none of these strains were STYMXB.0061 and the antimicrobial resistance was not linked to SGI1.Theprevalent identification and persistence ofDT120 isolates would suggest, in Southern Italy, a phage type shifting of the pandemic DT104 clone pulsotype STYMXB.0061.Additionally, these findings raise epidemiological concern about the potential diffusion of these emerging multidrug resistant (SGI linked) DT120 strains.

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Legionellae are opportunistic bacteria that cause various conditions after exposure to contaminated aerosols, ranging from a serious type of pneumonia to a mild case of an influenza-like illness. Despite the risks of exposure, little is known about the occurrence of Legionella in natural environments and, even though studies have shown that there is a potential risk of transmission via inhalation, it does not have to be detected in groundwater that is used for irrigation. The culture methods traditionally used to detect Legionella have several limits that can be partly solved by applying molecular techniques. Samples from 177 wells in Apulia, Southern Italy, were collected twice, in winter and in summer, and analyzed. When compared with the guidelines, 145 (81.9%) of the sampled wells were suitable for irrigation use. The culture-based method highlighted the presence of different species and serogroups of Legionella in 31 (21.2%) of the 145 wells that were shown to be suitable for irrigation use. A greater number of wells returned positive results for Legionella in summer than in winter (p = 0.023), and the median concentrations were mostly higher in summer (500 CFU/L) than in winter (300 CFU/L). The median temperature in the Legionella positive well waters was significantly higher than that in the negative ones, both in winter and in summer (p < 0.001). Using molecular techniques, Legionella non-pneumophila was found in 37 of the 114 wells earlier detected as suitable for irrigation use but negative for Legionella by the culture-based methods. The distribution of Legionella differ significantly in porous aquifers compared to the karst-fissured ones both with quantitative polymerase chain reaction (qPCR) (p = 0.0004) and viable cells by propidium monoazide (PMA-qPCR) (p = 0.0000). Legionella concentrations were weakly correlated with temperature of water both with qPCR (ρ = 0.47, p = 0.0033) and PMA-qPCR (ρ = 0.41, p = 0.0126). Our data suggest that water that aerosolizes when sprinkled on plants represents a potential source of Legionellosis, with a higher risk from exposure in summer. On a practical level, this finding is important for workers (farmers and gardeners) who are in contact with waters used for irrigation.

Twenty-four Salmonella enterica isolates (13 serovar Enteritidis and 11 Typhimurium) isolated from 5,600 samples from intensive laying hen farms in Italy in 1998-2007 were characterized for antimicrobial resistance genes, pulsotype and phage type. Most of S. Typhimurium strains were pulsotype STYMXB.0147 (81.8%), phage type DT143 and resistant to sulfamethoxazole encoded by sul2. Two multidrug resistant (MDR) strains were identified. One strain, STYMXB.0061, was resistant to ampicillin (A), chloramphenicol (C), streptomycin (S), sulfamethoxazole (Su) and tetracycline (T) encoded by the Salmonella Genomic Island SGI1. The second MDR strain, STYMXB.0110, was resistant to SSuT encoded by sul1 and sul2, aadA1 and tet(C)-flanked by an IS26 element, respectively. The tet(C) gene has been reported to confer low levels of resistance and it has very rarely been detected in S. Typhimurium from poultry. In the current study, the MIC value (32 µg/mL) was consistent with the breakpoint (³16 µg/mL) reported for Enterobacteriaceae. Most of the S. Enteritidis strains were resistant to Su (encoded by sul2). One MDR strain (ANxSSuT) was identified. With the exception of nalidixic acid (Nx), the resistances were respectively encoded by blaTEM, strAB, sul2 and tet(A) harbored by an IncN conjugative plasmid. All isolates were pulsotype SENTXB.0001 with PT14b being the most prevalent identified phage type (57.1%). In Europe, SENTXB.0001 is the predominant PFGE profile from clinical cases and the identification of PT14b has steadily been on the increase since 2001. The findings presented in this study highlight the potential spread of S. Enteritidis phage types PT14b and S. Typhimurium DT143 in a field of particular relevance for zoonoses. Additional, the presence of resistance genes and genetic elements (conjugative plasmid and IS element) underlines the need to assess routinely studies in field, such as poultry farms, relevant fot the public health and suitable for the storage and diffusion of antimicrobial resistance.

Salmonella enterica infections are not common in rabbits, but, whenever they occur, they induce high morbidity and mortality and they also raise concern in terms of public health impact. Moreover, the worldwide spread of multidrug resistant strains complicates the treatment of infection in both rabbits and humans. Despite those premises, knowledge about salmonelloses in rabbits is still poor. In this study four S. Typhimurium strains were isolated from as many rabbit farms, and they were characterized for antimicrobial susceptibility, resistance genes, class 1 integrons and Pulsed-Field Gel Electrophoresis (PFGE). The results showed that a group of strains were circulating in Basilicata, and that it was indistinguishable from human isolates for PFGE profile, multidrug resistance pattern and genetic features, as they harbored the Salmonella Genomic Island 1 (SGI1) which characterized the S. Typhimurium strains which are widespread among humans all over the world. Our data suggest that molecular characterization is a useful tool to promptly recognize Salmonella strains which are potentially harmful to rabbits or humans.

Abstract Background: H. pylori antibiotic resistance is an important factor in the treatment failure, therefore is important to know the local pattern of this resistance. Material and Methods: A total of 111 patients were studied. Ninety- one H. pylori strains isolated from patients, including 12 from children, having previous repeated treatment failure and 20 strains were isolated from naïve patients, were studied. Antibiotic susceptibility including those to tigecycline, was determinated by E-Test. Results: In treated adult and children patients the resistance rates were respectively 81% and 91.6% for clarithromycin; 27.8% and 41% for amoxicillin; 67.1% and 16.7% for metronidazole; 38% and 8.3% for levofloxacin; 5.1% and 0% for tetracycline. Primary resistance, in naïve adult patients was 50% for clarithromycin, 10% for amoxicillin, 20% for metronidazole, 30% for levofloxacin and 0% for tetracycline. Tigecycline has shown good activity, in vitro, against H. pylori (MIC90 = 0.064 mg/L). Conclusion: The resistance rates found in H. pylori, in our area, are very high both in naïve and treated patients. Few papers have reported the tigecycline susceptibility in H. pylori. The good activity and the lack of resistance to tigecycline found in our study, may consider this antibiotic a “rescue” therapy, saving the use of other antibiotics such as rifabutin, a drug used for the treatment of tuberculosis.

Salmonella enterica subsp. enterica serovar Gallinarum (S. Gallinarum) is the causative agent of fowl typhoid, one of the major causes of mortality and morbidity on poultry farms. Even though it has been substantially eradicated in many developed countries, the disease still remains endemic in Central and South America, in Africa and in the Mediterranean countries of Europe. This leads to the routine screening of flocks, mainly by cultivation and serological techniques, which are expensive, as well as time and labour-consuming. Here we describe a simple and specific PCR-based method for detecting S. Gallinarum. It relies on two seminested PCRs which use four pairs of primers designed on the basis of two genomic regions which appear to be exclusive to the pathogen. Furthermore, an internal positive control was devised in order to avoid any false negative results. We performed sensitivity and specificity tests, and our findings showed the cogency of the system and its potential effectiveness even for routine uses.

In this study we evaluated the in vitro variability of flaA in Campylobacter coli strains (Co19 and Co29) isolated from distinct poultry farms. Strains were characterized by flaA PCR-RFLP and subcultured in absence or presence of Salmonella enterica (S. Gallinarum) as a host competitor in poultry. Only transition mutations were detected and no flaA-flaB recombination events were observed. The highest ratio of flaA mutations was detected in the presence of competitor (1x10-6 and 4.8x10-6 for Co19 and Co29, respectively). While, transitions in absence of competitor were observed only in the strain Co29 (5.8x10-7). Data obtained in this investigation represent a preliminary study aimed to evaluate the possible linkage between specific haplotypes and their proneness to acquire point mutations which in turn might help strains to gain a better fitness for survival within and outside hosts.