Salmonellosis caused by Salmonella enterica serovar Newport is a major global public health concern, particularly because S. Newport isolates that are resistant to multiple drugs (MDR), including thirdgeneration cephalosporins (MDR-AmpC phenotype), have been commonly isolated from food animals. We analyzed 384 S. Newport isolates from various sources by a multilocus sequence typing (MLST) scheme to study the evolution and population structure of the serovar. These were compared to the population structure of S. enterica serovars Enteritidis, Kentucky, Paratyphi B, and Typhimurium. Our S. Newport collection fell into three lineages, Newport-I, Newport-II, and Newport-III, each of which contained multiple sequence types (STs). Newport-I has only a few STs, unlike Newport-II or Newport-III, and has possibly emerged recently. Newport-I is more prevalent among humans in Europe than in North America, whereas Newport-II is preferentially associated with animals. Two STs of Newport-II encompassed all MDR-AmpC isolates, suggesting recent global spread after the acquisition of the bla CMY-2 gene. In contrast, most Newport-III isolates were from humans in North America and were pansusceptible to antibiotics. Newport was intermediate in population structure to the other serovars, which varied from a single monophyletic lineage in S. Enteritidis or S. Typhimurium to four discrete lineages within S. Paratyphi B. Both mutation and homologous recombination are responsible for diversification within each of these lineages, but the relative frequencies differed with the lineage. We conclude that serovars of S. enterica provide a variety of different population structures.Salmonellosis is a major global cause of diarrheal and extraintestinal disease in humans and animals (66). Salmonella enterica subspecies enterica (referred to herein as S. enterica) has been subdivided serologically into Ͼ1,500 serovars (35), but we focus on S. enterica serovar Newport (S. Newport) here because over the last decade it has been a very common cause of human salmonellosis in both the United States and Europe (13,16,27). Furthermore, multidrug-resistant S. Newport isolates that are also resistant to extended-spectrum cephalosporins (MDR-AmpC) have now been reported from several countries (3,24,36) and are a serious problem among both food animals and humans (17,25,36,48,67). MDR-AmpC isolates are resistant to -lactams, including third-generation cephalosporins, aminoglycosides, tetracyclines, sulfonamides and chloramphenicol (12, 36). Resistance to -lactams is caused by plasmids carrying the ampC gene bla CMY-2 , which encodes the CMY-2 -lactamase (11,65).Most of our current understanding of the population structure of S. enterica relies on a series of seminal publications from R. K. Selander's group in the 1990s. These publications showed that some serovars consisted of monophyletic groups-so-called clonal groupings-but many other serovars confounded isolates from multiple lineages and were therefore polyphyletic (5,51,55,56). More recent studie...
To our knowledge this is the first report of molecular characterization of S. Typhi with full resistance to ciprofloxacin. Notably, the presence of a plasmid-borne integron in ciprofloxacin-resistant S. Typhi may lead to a situation of untreatable enteric fever.
Synergistic combinations of antimicrobial agents with different mechanisms of action have been introduced as more successful strategies to combat infections involving multidrug resistant (MDR) bacteria. In this study, we investigated synergistic antimicrobial activity of Camellia sinensis and Juglans regia which are commonly used plants with different antimicrobial agents. Antimicrobial susceptibility of 350 Gram-positive and Gram-negative strains belonging to 10 different bacterial species, was tested against Camellia sinensis and Juglans regia extracts. Minimum inhibitory concentrations (MICs) were determined by agar dilution and microbroth dilution assays. Plant extracts were tested for synergistic antimicrobial activity with different antimicrobial agents by checkerboard titration, Etest/agar incorporation assays, and time kill kinetics. Extract treated and untreated bacteria were subjected to transmission electron microscopy to see the effect on bacterial cell morphology. Camellia sinensis extract showed higher antibacterial activity against MDR S. Typhi, alone and in combination with nalidixic acid, than to susceptible isolates.” We further explore anti-staphylococcal activity of Juglans regia that lead to the changes in bacterial cell morphology indicating the cell wall of Gram-positive bacteria as possible target of action. The synergistic combination of Juglans regia and oxacillin reverted oxacillin resistance of methicillin resistant Staphylococcus aureus (MRSA) strains in vitro. This study provides novel information about antimicrobial and synergistic activity of Camellia sinensis and Juglans regia against MDR pathogens
We are living in times where a viral disease has brought normal life in much of the world to a halt. The novel coronavirus known as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causing coronavirus disease 2019 (COVID-19) started in December 2019 in Wuhan, China initially and in a short time crossed the European borders. After mitigating the epidemic in China, Italy became one of the most COVID-19 affected countries worldwide. International travelers are important sources of infectious diseases and a possible source of epidemic. Due to its political, geographic, and cultural similarities, Italy is one of the main economic partners of Southeast European (SEE) countries. Our data show that infection in index cases in all 11 SEE countries was travel-related with Italy being a source country for 8/11 countries. After the first case identifications on February 25, the number of cases in SEE countries is continually rising reaching the total number of 15,612 with 565 fatal cases and overall case fatality ratio (CFR) of 3.6 (median 3.8, range 0.8–5.5) by April 10, 2020. At a time when the COVID-19 pandemic is approaching its peak, apart from the problems with treatment of the disease and care for critically ill patients, there are other equally important problems, such as organization of outbreak response, provision of health care, lack of hospital personnel, disruption of personal protective equipment supply chains and health care workers (HCWs) protection. But what is more important is the heroic behavior of the HCWs who are showing their humanity by disregarding their lives.
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