Antibiotic and Heavy Metal Susceptibility of Non-Cholera Vibrio Isolated from Marine Sponges and Sea Urchins: Could They Pose a Potential Risk to Public Health?

Vibrio is an important human and animal pathogen that can carry clinically relevant antibiotic resistance genes and is present in different aquatic environments. However, there is a knowledge gap between antibiotic and heavy metal resistance and virulence potential when it is part of the microbiota from marine invertebrates. Here, we aimed to evaluate these characteristics and the occurrence of mobile genetic elements. Of 25 non-cholera Vibrio spp. from marine sponges and sea urchins collected at the coastlines of Brazil and France analyzed in this study, 16 (64%) were non-susceptible to antibiotics, and two (8%) were multidrug-resistant. Beta-lactam resistance (blaSHV) and virulence (vhh) genes were detected in sponge-associated isolates. The resistance gene for copper and silver (cusB) was detected in one sea urchin isolate. Plasmids were found in 11 (44%) of the isolates. This new information allows a better comprehension of antibiotic resistance in aquatic environments, since those invertebrates host resistant Vibrio spp. Thus, Vibrio associated with marine animals may pose a potential risk to public health due to carrying these antibiotic-resistant genes.

El Tor cholera at the contemporary stage of the seventh pandemia: pathogen evolution, clinical and epidemiological features, laboratory diagnostics

The phenotypic and molecular genetic properties of 133 strains of genetically modified (genovariant) Vibrio cholerae O1 El Tor biovar isolated from patients in Dagestan (1993, 1994, 1998), and compared with 246 strains of a typical toxigenic cholera vibrio El Tor biovar isolated in 1970–1990 at the Caucasus Region. It was found that 48.7% of the studied genetically modified strain variants had mixed phenotypic properties of the El Tor and classic biovars that evidences about a need to include the marker genes of the classical biovar (ctxBCl+, rtxC–) and the El Tor biovar (ctxBEl+, rtxC+) into the existing biotyping scheme. The genes of the El Tor biovar, isolated from patients in Dagestan, contain in addition to the El Tor ones, the genes of the classical biovar (ctxBCl and/or rstRCl), as well as the typical toxigenic cholera vibrios of El Tor, islands of persistence (EPI), pathogenicity (VPI-1 and VPI-2) and pandemicity (VSP-I and VSP-II). However, only the El Tor biovar genovariants were found to bear an integrative and conjugative SXT element with antibiotic polyresistance genes. Epidemic cholera outbreaks caused by the El Tor biovar genovariants that occurred in 1993–1998 at the Caucasus Region, correspond to classical (Asian) cholera based on disease severity. The epidemiological features of modern cholera were studied: the main way for transmission via fecal-oral route for typical El Tor cholera vibrio is waterborne, whereas for the El Tor gene variant — household. Primary infections upon water drinking and using domestic water from surface water bodies infected with typical El Tor vibrios occur outside the family hearth. In case of cholera caused by hybrid El Tor variants, infection is transmitted among family members via domestic factors under low sanitary level. The development of laboratory diagnostics and epidemiological surveillance of modern El Tor cholera is based on the development of PCR test systems taking into account the evolutionary genome transformations.

Identification of Vibrio cholerae O1 strains of the El Tor biovar sensitive to polymyxin B and their molecular genetic analysis

The aim of the work was the identification and genetic characterization of Vibrio cholerae O1 strains of the El Tor biovar sensitive to polymyxin B among isolates imported to Russia.Materials and methods. We used 56 toxigenic and non-toxigenic strains of V. cholerae isolated from patients and from the environmental samples on the territory of Russia in 1970-2020. Resistance to polymyxin B was determined according to MR4.2.2218-07. The ability of strains to form a biofilm on the abiotic surface was assessed by a photometric method. Nucleotide sequences of genes were determined using UGENE 1.32 and MEGA X software. Phylogenetic analysis and tree construction were performed using "maximum parsimony" method in MEGA X software.Results and discussion. Two genetically modified strains of V. cholerae O1 biovar El Tor, M1509 and 3265/80, which were imported to Russia from India in 2012 and 2014, respectively, were identified. The analysis of 12 genes responsible for the resistance of V. cholerae O1 biovar El Tor strains to polymyxin B demonstrated that these strains contain the allele of the carRS gene, which is typical for all strains of cholera vibrio sensitive to polymyxin B. Study of V. cholerae M1509 and 3265/80 phylogeny based on SNP analysis showed that they fall into the same cluster with isolates containing the carRS allele isolated in India (2015) and Bangladesh (2018). V. cholerae M1509 and 3256/8 strains had the ability to form a biofilm similar to those observed in other genetically modified strains of cholera vibrio included into analysis.Conclusion. Highly virulent strains of the cholera agent with altered diagnostically significant features are imported into Russia, which should be taken into account when identifying V. cholerae O1 biovar El Tor strains isolated from patients and environmental samples during monitoring studies.

Prevalence of Vibrio Cholerae and Vibrio Species from Different Sources in Bayelsa State, Nigeria

The distribution of Vibrio cholerae and non-cholera Vibrio species from different sources from five localities in Bayelsa State, Nigeria was investigated in this study. A total of 44 stool samples, 22 freshwater samples, 60 brackish water samples and 64 seafood samples (crabs, shrimps and fishes) were collected from January to April, 2019 for the purpose of V. cholerae prevalence study. Samples were transported to the laboratory using Car-Blair’s medium. This was followed by samples enrichment in 1% alkaline peptone water and pour plating on thiosulphate citrate bile-salt sucrose (TCBS) agar. Characteristic yellow colonies were subjected to further biochemical and physiological characterization to further identify V. cholerae. Antibiotics susceptibility patterns for isolated V. cholerae strains were investigated. Furthermore, water samples (fresh and brackish) and seafood samples were collected on a monthly basis to ascertain the effect of seasons (dry and wet months) on the distribution of Vibrio spp. A total of 16 (36.36%) stools samples were positive for V. cholerae. In addition, 12 (54.55%) of freshwater samples, 28 (46.67%) of brackish water samples and 22 (34.38%) of seafood samples were contaminated with V. cholerae. The monthly mean values of Vibrio spp. from environmental sources showed statistically significant difference (P<0.05) between the dry months (low rainfall) and wet months (frequent rainfall). Higher average values were observed during the dry months. The result of the antibiotics sensitivity test showed all V. cholerae strains were susceptible to ciprofloxacin, ofloxacin and pefloxacin while varying degree sensitivities were observed in tetracycline and augmentin. Cholera and other non-cholera Vibrio spp gastrointestinal infections are still a major concern to the health of the public. Local and regional governments should enforce and promote the need for personal and communal hygienic practices.

Brief outline of the history of world epidemics-pandemics Part II. Cholera nineteenth

An epidemic of any infectious disease is an invisible ruthless enemy that cannot be defeated by military, political, economic or ideological means. Humanity always reacts to such threats quite nervously and subconsciously tries to mythologize them, at least a little, in order to somehow psychologically protect itself from the real fear of imminent death. Since there is no rational defense against such a threat, people for the most part react in an irrational manner.The 19th century, almost the same as the previous centuries, «started» in epidemiological terms almost from the very beginning of its calendar. Only in contrast to the previous 18th century, the main and dominant danger was posed by another infectious pathology — cholera.In the history of medicine, over the 19th century, as many as six outbreaks of cholera epidemics were recorded since 1817. The first of them began in East Bengal and lasted 8 years (1817—1824), gradually, covering almost all India and big regions of the Middle East. It was worsened by the traditional travels of both Hindu and Muslim pilgrims to «holy places» who spread Vibrio cholerae on foot and through active communication with local residents.One of the significant reasons why cholera epidemic continued with minimal interruptions for almost the entire nineteenth century was an insufficient level of scientific knowledge in microbiology and the resulting ignorance of the causative agent of cholera — vibrio and its properties.Another factor was a complete lack of understanding by society of the need to observe at least the simplest sanitary standards in everyday life. And there was also misunderstanding among the leadership which tried to limit the next outbreak of cholera mainly by administrative measures without adequate explanations of their essence and necessity to the population.

Pheno- and Genotypical Features of Non-Toxigenic Strains of Cholera Vibrios of Different Origins, Isolated in the Territory of Russia

Aim. Analysis of the phenotypic characteristics and identification of peculiarities of the genotypic organization in non-toxigenic strains of cholera vibrios having different origin, isolated in Russia. Materials and methods. A sample of 548 non-toxigenic strains obtained using the author’s updated GIS “Cholera 1989–2014” was used. PCR genotyping was carried out in accordance with the patented “Method for the identification of non-toxigenic strains of cholera vibrio O1 serogroup using PCR to isolate genetic determinants.” Cluster analysis was performed applying the UPGMA method. The dendrogram was constructed using MEGA 5 software package.Results and discussion. Representative cultural-morphological, serological and biochemical properties of V. cholerae strains have been specified. The variability of the studied strains on the basis of phagolizability has been revealed. Unique phage-types not previously encountered in Russia have been identified. The population of non-toxigenic strains of cholera vibrio O139 serogroup is genetically homogeneous in contrast to V. cholerae O1 El Tor isolates and has identical PCR genotypes. The universality of the PCR genotyping by 14 target genes has been shown to differentiate the studied strains of V. cholerae O1 and O139, as well as to identify disparities among O139 strains isolated in different geographical regions of the country.

Dominant Vibrio cholerae phage exhibits lysis inhibition sensitive to disruption by a defensive phage satellite

Bacteria, bacteriophages that prey upon them, and mobile genetic elements (MGEs) compete in dynamic environments, evolving strategies to sense the milieu. The first discovered environmental sensing by phages, lysis inhibition, has only been characterized and studied in the limited context of T-even coliphages. Here, we discover lysis inhibition in the etiological agent of the diarrheal disease cholera, Vibrio cholerae, infected by ICP1, a phage ubiquitous in clinical samples. This work identifies the ICP1-encoded holin, teaA, and antiholin, arrA, that mediate lysis inhibition. Further, we show that an MGE, the defensive phage satellite PLE, collapses lysis inhibition. Through lysis inhibition disruption a conserved PLE protein, LidI, is sufficient to limit the phage produced from infection, bottlenecking ICP1. These studies link a novel incarnation of the classic lysis inhibition phenomenon with conserved defensive function of a phage satellite in a disease context, highlighting the importance of lysis timing during infection and parasitization.