Phenotypic and molecular typing of Vibrio cholerae O1 and O139 isolates from India

Antimicrobial resistance among clinical Vibrio cholerae non-O1/non-O139 isolates: systematic review and meta-analysis

Non-O1/non-O139 Vibrio cholerae (NOVC) are nonpathogenic or asymptomatic colonizers in humans, but they may be related to intestinal or extra-intestinal (severe wound infections or sepsis) infections in immunocompromised patients.The present study aimed to evaluate the weighted pooled resistance (WPR) rates in clinical NOVC isolates based on different years, areas, quality, antimicrobial susceptibility testing (AST), and resistance rates. We systematically searched the articles in PubMed, Scopus, and Embase (until January 2020). Data analyses were performed using the Stata software program (version 17). A total of 16 studies that had investigated 824 clinical NOVC isolates were included in the meta-analysis. The majority of the studies were conducted in Asia (n = 14) and followed by Africa (n = 2). The WPR rates were as follows: erythromycin 10%, ciprofloxacin 5%, cotrimoxazole 27%, and tetracycline 13%. There was an increase in resistance to ciprofloxacin, nalidixic acid, and gentamicin, norfloxacin during the period from 2000 to 2020. On the contrary, there was a decreased resistance to erythromycin, tetracycline, chloramphenicol, cotrimoxazole, ampicillin, streptomycin, kanamycin, and neomycin during the period from 2000 to 2020. The lowest resistance rate were related to gentamicin, kanamycin, ciprofloxacin, and chloramphenicol against NOVC strains. However, temporal changes in antimicrobial resistance rate were found in our study. We established continuous surveillance, careful appropriate AST, and limitations on improper antibiotic usage, which are essential, especially in low-income countries.

Resistance of Vibrio cholera to antibiotics that inhibit cell wall synthesis: A systematic review and meta-analysis

Objective: Cholera is a challenging ancient disease caused by Vibrio cholera (V. cholera). Antibiotics that prevent cell wall synthesis are among the first known antibiotic groups. Due to its high consumption, V. cholera has developed resistance to the majority of antibiotics in this class. Resistance to recommended antibiotics for the treatment of V. cholera has also increased. In light of the decrease in consumption of certain antibiotics in this group that inhibit cell wall synthesis and the implementation of new antibiotics, it is necessary to determine the antibiotic resistance pattern of V. cholera and to employ the most effective treatment antibiotic. Method: An comprehensive systematic search for relevant articles was conducted in PubMed, Web of Science, Scopus, and EMBASE through October 2020. Stata version 17.1 utilized the Metaprop package to execute a Freeman-Tukey double arcsine transformation in order to estimate weighted pooled proportions. Results: A total of 131 articles were included in the meta-analysis. Ampicillin was the most investigated antibiotic. The prevalence of antibiotic resistance was in order aztreonam (0%), cefepime (0%), imipenem (0%), meropenem (3%), fosfomycin (4%), ceftazidime (5%), cephalothin (7%), augmentin (8%), cefalexin (8%), ceftriaxone (9%), cefuroxime (9%), cefotaxime (15%), cefixime (37%), amoxicillin (42%), penicillin (44%), ampicillin (48%), cefoxitin (50%), cefamandole (56%), polymyxin-B (77%), carbenicillin (95%) respectively. Discussion: Aztreonam, cefepime, and imipenem are the most efficient V. cholera cell wall synthesis inhibitors. There has been an increase in resistance to antibiotics such as cephalothin, ceftriaxone, amoxicillin, and meropenem. Over the years, resistance to penicillin, ceftazidime, and cefotaxime, has decreased.

Antimicrobial resistance in Vibrio cholerae O1/O139 clinical isolates: a systematic review and meta-analysis

OBJECTIVES

Vibrio cholerae O1/O139 is responsible for cholera epidemics; that remains a huge public health menace across the globe. Furthermore, an increasing resistance rate among V. cholerae strains has been reported around the world. Therefore, the objective of this meta-analysis was to evaluate the weighted pooled resistance (WPR) rates in clinical V. cholerae O1/O139 isolates based on different years, areas, antimicrobial susceptibility testing, and resistance rates.

RESEARCH DESIGN AND METHODS

: We searched the studies in PubMed, Scopus, Embase, and Web of Science (until January 2020). Statistical analyses were conducted using STATA software (ver. 14.0).

RESULTS

: A total of 139 studies investigating 24062 V. cholerae O1/O139 isolates were analyzed. The majority of the studies originated in Asia (n=102). The WPR rates were as follows: azithromycin 1%, erythromycin 36%, ciprofloxacin 3%, cotrimoxazole 79%, doxycycline 7%, tetracycline 20%. There was increased resistance to cotrimoxazole, ciprofloxacin, and tetracycline during the 1980 to 2020 years.

CONCLUSIONS

: Temporal changes in antibiotic resistance rate found in this study demonstrated the critical continuous surveillance of antibiotic resistance. Also, ciprofloxacin, azithromycin, gentamicin, cephalexin, imipenem, ofloxacin, and norfloxacin were found to be the best antibiotics against V. cholera, with the highest and the lowest effectiveness resistance rate.

Trends in the genomic epidemiology of Vibrio cholerae O1 isolated worldwide since 1961

Here we describe the international scenario of Vibrio cholerae with a comparative analysis of different aspects of typing. Representative V. cholerae strains (n=108) associated with endemic cholera regions from 29 states of India and worldwide were subjected to microbiological, molecular and phylogenetic study. All of the strains were V. cholerae serogroup O1 biotype El Tor and were typed according to both the new phage (NP) type and Basu & Mukherjee (BM) typing schemes. The predominant phage type was T-27 (NP)/T-4 (BM) (65.7%; n=71), followed by phage type T-27 (NP)/T-2 (BM) (14.8%; n=16), T-26 (NP)/T4 (BM) (12.0%; n=13), T-13 (NP)/T-4 (BM) (2.8%; n=3), T-20 (NP)/T-4 (BM) (1.9%; n=2), T-3 (NP)/T-4 (BM) (0.9%; n=1), T-23 (NP)/T-4 (BM) (0.9%; n=1) and T-24 (NP)/T-2 (BM) (0.9%; n=1). Mismatch amplification mutation assay PCR (MAMA-PCR) findings showed the dominance of ctxB El Tor genotype (77.1%; 54/70) from 1961-1991, whilst the next two epochs showed the supremacy of ctxB classical genotype. Multidrug-resistant strains showed resistance to erythromycin, streptomycin, trimethoprim/sulfamethoxazole, norfloxacin and ampicillin. The regional resistance of epidemic clones in India draws a layout of the rapid dissemination of resistance in the past 30 years and the necessity of proper treatment to protect populations at risk.

Fitness factors in vibrios: a mini-review

Vibrios are Gram-negative curved bacilli that occur naturally in marine, estuarine, and freshwater systems. Some species include human and animal pathogens, and some vibrios are necessary for natural systems, including the carbon cycle and osmoregulation. Countless in vivo and in vitro studies have examined the interactions between vibrios and their environment, including molecules, cells, whole animals, and abiotic substrates. Many studies have characterized virulence factors, attachment factors, regulatory factors, and antimicrobial resistance factors, and most of these factors impact the organism's fitness regardless of its external environment. This review aims to identify common attributes among factors that increase fitness in various environments, regardless of whether the environment is an oyster, a rabbit, a flask of immortalized mammalian cells, or a planktonic chitin particle. This review aims to summarize findings published thus far to encapsulate some of the basic similarities among the many vibrio fitness factors and how they frame our understanding of vibrio ecology. Factors representing these similarities include hemolysins, capsular polysaccharides, flagella, proteases, attachment factors, type III secretion systems, chitin binding proteins, iron acquisition systems, and colonization factors.

Association of Heavy Rainfall on Genotypic Diversity in V. cholerae Isolates from an Outbreak in India

The outbreak of waterborne disease cholera has been associated with rainfall and flooding events by contamination of potable water with environmental Vibrio cholerae. The continuation of the epidemic in a region, however, is often due to secondary transmission of the initial outbreak strain through human waste. This paper reports, on the contrary, a rapid shift of genotype from one V. cholerae strain to another one in an epidemic region. V. cholerae isolated from patients during 2005 cholera epidemic in Chennai, India were characterized using PCR identification of toxin genes, antibiogram, and genomic fingerprinting analysis. The results showed that in spite of the similarity of toxin genes and antibiogram, the Vibrio isolates grouped into two different clusters based on the ERIC-PCR fingerprinting. Each cluster corresponded to a distinct peak of cholera outbreak, which occurred after separate heavy rainfall. The results suggest that the rainfall event can bring various genotypes of V. cholerae strains causing multiple outbreaks.

Genotypic characterization of Vibrio cholerae isolates using several DNA fingerprint techniques

Serious pandemics of cholera have occurred throughout the known history of mankind, especially in India, which is a motherland for cholera disease. For the last 20 years several DNA-based typing methods have been employed to study the clonal relatedness between Vibrio cholerae isolates irrespective of their geographical locations. Traditional typing methods, such as biochemical tests, phage typing, serotyping, biotyping and antimicrobial susceptibility tests, have produced reliable and informative data regarding V. cholerae for a long time. Gradually molecular typing techniques have taken the place of traditional typing methods because they produce the same results upon repeat testing of V. cholerae strain. In this article we focus on the discriminatory power of different DNA fingerprint techniques that are generally used to know the homogeneity and heterogeneity among different V. cholerae isolates.

Evaluation of VcA VNTR as a strain-typing and phylogeny study method of Vibrio cholerae strains

This study attempted to examine the relatedness between RAPD-PCR, PFGE and VcA VNTR results with those of conventional phage typing of V. cholerae strains and to evaluate VcA VNTR as an indispensable molecular-typing tool that accomplishes the urgent need for effective epidemiological surveillance. All the O1 El Tor strains were predominantly clustered into phage type T27 with the new phage-typing scheme. Using RAPD-PCR, a total of 69 O1 El Tor strains were grouped under 16 different electrophoretic patterns. A total of 33 pulsotypes were identified in these strains by PFGE. VcA VNTR revealed high VcA polymorphism in all V. cholerae strains incorporated in this study. Our results underline the considerable potential of VcA VNTR analysis as a tool for molecular typing of V. cholerae.

Detection of virulence-associated and regulatory protein genes in association with phage typing of human Vibrio cholerae from several geographical regions of the world

Vibrio cholerae O1, O139 and occasionally non-O1/non-O139 serogroups are most often responsible for epidemic and pandemic cholera. This study used genotypic patterns of PCR-based detection of virulence-associated and regulatory protein genes, along with phage typing, to characterize 86 V. cholerae strains. Thirty-eight of 53 O1 biotype El Tor strains harboured both tcpA classical and tcpA El Tor genes, and three El Tor strains lacked the V. cholerae O1-specific gene (Vc-O1); three O139 strains contained both Vc-O1 and Vc-O139 genes and seven out of ten non-O1/non-O139 strains possessed the Vc-O1 gene. The latter strains all harboured the virulence-associated genes ctxA, zot, ace, RS1, hlyA, ompU, rtxA and sxt. Two phage types, T27 and T25, were predominant in strains from different geographical regions of India, whereas more variation in phage susceptibility was observed for tetracycline-resistant strains from Kolkata. These results suggest that the pattern and distribution of virulence genes and phage types of V. cholerae are equally useful and discriminatory in tracing the origin of newly emerging strains.