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Scientific Reports Apr 2022The comprehensive effect size of several commercial vaccines and vaccine candidates against edema disease (ED) has not been evaluated to date. To integrate the... (Meta-Analysis)
Meta-Analysis
The comprehensive effect size of several commercial vaccines and vaccine candidates against edema disease (ED) has not been evaluated to date. To integrate the effectiveness of ED vaccines reported so far and to compare and evaluate the posterior-effect estimates of each vaccine type with network models, we identified eligible studies (n = 12) from the electronic databases using specified search strings. Data for dichotomous outcomes (i.e., mortality and clinical symptoms) and continuous outcomes (i.e., fecal shedding and average daily gain) were extracted and analyzed. Conventional meta-analysis shows that, compared with that in non-vaccinated pigs, vaccinated animals are likely to show reduced mortality (OR = 0.07) and clinical signs of ED (OR = 0.11), and increased productivity (SMD = 0.73). Although reduced fecal shedding (SMD = - 1.29) was observed in vaccinated pigs, this could not be fully determined on insufficient grounds. In contrast to mortality and clinical symptoms, fecal shedding (I = 88%) and average daily gain (I = 85%) showed immense heterogeneity, which was attributed to the small sample size and vaccination route, respectively. According to the Bayesian network meta-analysis, the plasmid-based DNA vaccine demonstrated a better effect for all outcomes compared to other types of vaccines. However, these findings should be carefully interpreted with consideration to potential mediators, insufficient data, and inconsistent network models.
Topics: Animals; Bayes Theorem; Edema; Edema Disease of Swine; Escherichia coli Infections; Network Meta-Analysis; Shiga-Toxigenic Escherichia coli; Swine; Vaccine Efficacy
PubMed: 35440612
DOI: 10.1038/s41598-022-10439-x -
Microorganisms Mar 2022Beta-lactamase (BL) production is a major public health problem. Although not the most frequent AmpC type, AmpC-BL is increasingly isolated, especially plasmid AmpC-BL...
Beta-lactamase (BL) production is a major public health problem. Although not the most frequent AmpC type, AmpC-BL is increasingly isolated, especially plasmid AmpC-BL (pAmpC-BL). The objective of this study was to review information published to date on pAmpC-BL in and and on the epidemiology and detection methods used by clinical microbiology laboratories, by performing a systematic review using the MEDLINE PubMed database. The predictive capacity of a screening method to detect AmpC-BL using disks with cloxacillin (CLX) was also evaluated by studying 102 clinical isolates grown in CHROMID ESBL medium with the addition of cefepime (FEP), cefoxitin (FOX), ertapenem (ETP), CLX, and oxacillin with CLX. The review, which included 149 publications, suggests that certain risk factors (prolonged hospitalization and previous use of cephalosporins) are associated with infections by pAmpC-BL-producing microorganisms. The worldwide prevalence has increased over the past 10 years, with a positivity rate ranging between 0.1 and 40%, although AmpC was only detected when sought in a targeted manner. CMY-2 type has been the most prevalent pAmpC-BL-producing microorganism. The most frequently used phenotypic method has been the double-disk synergy test (using CLX disks or phenyl-boronic acid and cefotaxime [CTX] and ceftazidime) and the disk method combined with these inhibitors. In regard to screening methods, a 1-µg oxacillin disk with CLX showed 88.9% sensitivity, 100% specificity, 100% positive predictive value (PPV), 98.9% negative predictive value (NPV), and 98.9% validity index (VI). This predictive capacity is reduced with the addition of extended-spectrum beta-lactamases, showing 62.5% sensitivity, 100% specificity, 100% PPV, 93.5% NPV, and 94.1% VI. In conclusion, there has been a worldwide increase in the number of isolates with pAmpC-BL, especially in Asia, with CMY-2 being the most frequently detected pAmpC-BL-producing type of microorganism. Reduction in its spread requires routine screening with a combination of phenotypic methods (with AmpC inhibitors) and genotypic methods (multiplex PCR). In conclusion, the proposed screening technique is an easy-to-apply and inexpensive test for the detection of AmpC-producing isolates in the routine screening of multidrug-resistant microorganisms.
PubMed: 35336186
DOI: 10.3390/microorganisms10030611 -
Osong Public Health and Research... Feb 2022Yersinia pestis, the cause of plague and a potential biological weapon, has always been a threatening pathogen. Some strains of Y. pestis have varying degrees of...
Yersinia pestis, the cause of plague and a potential biological weapon, has always been a threatening pathogen. Some strains of Y. pestis have varying degrees of antibiotic resistance. Thus, this systematic review was conducted to alert clinicians to this pathogen's potential antimicrobial resistance. A review of the literature was conducted for experimental reports and systematic reviews on the topics of plague, Y. pestis, and antibiotic resistance. From 1995 to 2021, 7 Y. pestis isolates with 4 antibiotic resistance mechanisms were reported. In Y. pestis 17/95, 16/95, and 2180H, resistance was mediated by transferable plasmids. Each plasmid contained resistance genes encoded within specific transposons. Strain 17/95 presented multiple drug resistance, since plasmid 1202 contained 10 resistance determinants. Strains 16/95 and 2180H showed single antibiotic resistance because both additional plasmids in these strains carried only 1 antimicrobial determinant. Strains 12/87, S19960127, 56/13, and 59/13 exhibited streptomycin resistance due to an rpsl gene mutation, a novel mechanism that was discovered recently. Y. pestis can acquire antibiotic resistance in nature not only via conjugative transfer of antimicrobial-resistant plasmids from other bacteria, but also by gene point mutations. Global surveillance should be strengthened to identify antibiotic-resistant Y. pestis strains by whole-genome sequencing and drug susceptibility testing.
PubMed: 35255676
DOI: 10.24171/j.phrp.2021.0288 -
Antibiotics (Basel, Switzerland) Feb 2022Antimicrobial resistance to treatments for infection (CDI) poses a significant threat to global health. is widely thought to be susceptible to oral vancomycin, which... (Review)
Review
Antimicrobial resistance to treatments for infection (CDI) poses a significant threat to global health. is widely thought to be susceptible to oral vancomycin, which is increasingly the mainstay of CDI treatment. However, clinical labs do not conduct susceptibility testing, presenting a challenge to detecting the emergence and impact of resistance. In this systematic review, we describe gene determinants and associated clinical and laboratory mechanisms of vancomycin resistance in , including drug-binding site alterations, efflux pumps, RNA polymerase mutations, and biofilm formation. Additional research is needed to further characterize these mechanisms and understand their clinical impact.
PubMed: 35203860
DOI: 10.3390/antibiotics11020258 -
Antimicrobial Resistance and Infection... Jan 2022Antimicrobial resistance is swiftly increasing all over the world. In Africa, it manifests more in pathogenic bacteria in form of antibiotic resistance (ABR). On this... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Antimicrobial resistance is swiftly increasing all over the world. In Africa, it manifests more in pathogenic bacteria in form of antibiotic resistance (ABR). On this continent, bacterial contamination of commonly used herbal medicine (HM) is on the increase, but information about antimicrobial resistance in these contaminants is limited due to fragmented studies. Here, we analyzed research that characterized ABR in pathogenic bacteria isolated from HM in Africa since 2000; to generate a comprehensive understanding of the drug-resistant bacterial contamination burden in this region.
METHODS
The study was conducted according to standards of the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA). We searched for articles from 12 databases. These were: PubMed, Science Direct, Scifinder scholar, Google scholar, HerbMed, Medline, EMBASE, Cochrane Library, International Pharmaceutical Abstracts, Commonwealth Agricultural Bureau Abstracts, African Journal Online, and Biological Abstracts. Prevalence and ABR traits of bacterial isolates, Cochran's Q test, and the I statistic for heterogeneity were evaluated using MedCalcs software. A random-effects model was used to determine the pooled prevalence of ABR traits. The potential sources of heterogeneity were examined through sensitivity analysis, subgroup analysis, and meta-regression at a 95% level of significance.
FINDINGS
Eighteen studies met our inclusion criteria. The pooled prevalence of bacterial resistance to at least one conventional drug was 86.51% (95% CI = 61.247-99.357%). The studies were highly heterogeneous (I = 99.17%; p < 0.0001), with no evidence of publication bias. The most prevalent multidrug-resistant species was Escherichia coli (24.0%). The most highly resisted drug was Ceftazidime with a pooled prevalence of 95.10% (95% CI = 78.51-99.87%), while the drug-class was 3 generation cephalosporins; 91.64% (95% CI = 78.64-96.73%). None of the eligible studies tested isolates for Carbapenem resistance. Extended Spectrum β-lactamase genes were detected in 89 (37.2%) isolates, mostly Salmonella spp., Proteus vulgaris, and K. pneumonia. Resistance plasmids were found in 6 (5.8%) isolates; the heaviest plasmid weighed 23,130 Kilobases, and Proteus vulgaris harbored the majority (n = 5; 83.3%).
CONCLUSIONS
Herbal medicines in Africa harbor bacterial contaminants which are highly resistant to conventional medicines. This points to a potential treatment failure when these contaminants are involved in diseases causation. More research on this subject is recommended, to fill the evidence gaps and support the formation of collaborative quality control mechanisms for the herbal medicine industry in Africa.
Topics: Africa; Anti-Bacterial Agents; Bacteria; Drug Contamination; Drug Resistance, Bacterial; Food Contamination; Herbal Medicine
PubMed: 35063036
DOI: 10.1186/s13756-022-01054-6 -
Virology Journal Dec 2021Vaccination against HCV is an effective measure in reduction of virus-related public health burden and mortality. However, no prophylactic vaccine is available as of...
BACKGROUND
Vaccination against HCV is an effective measure in reduction of virus-related public health burden and mortality. However, no prophylactic vaccine is available as of yet. DNA-based immunization is a promising modality to generate cellular and humoral immune responses. The objective of this study is to provide a systematic review of HCV DNA vaccines and investigate and discuss the strategies employed to optimize their efficacies.
METHODS
MEDLINE (PubMed), Web of Science, Scopus, ScienceDirect, and databases in persian language including the Regional Information Centre for Science & Technology (RICeST), the Scientific Information Database and the Iranian Research Institute for Information Science and Technology (IranDoc) were examined to identify studies pertaining to HCV nucleic acid vaccine development from 2000 to 2020.
RESULTS
Twenty-seven articles were included. Studies related to HCV RNA vaccines were yet to be published. A variety of strategies were identified with the potential to optimize HCV DNA vaccines such as incorporating multiple viral proteins and molecular tags such as HBsAg and Immunoglobulin Fc, multi-epitope expression, co-expression plasmid utilization, recombinant subunit immunogens, heterologous prime-boosting, incorporating NS3 mutants in DNA vaccines, utilization of adjuvants, employment of less explored methods such as Gene Electro Transfer, construction of multi- CTL epitopes, utilizing co/post translational modifications and polycistronic genes, among others. The effectiveness of the aforementioned strategies in boosting immune response and improving vaccine potency was assessed.
CONCLUSIONS
The recent progress on HCV vaccine development was examined in this systematic review to identify candidates with most promising prophylactic and therapeutic potential.
Topics: Animals; Hepacivirus; Hepatitis C; Humans; Iran; Mice; Mice, Inbred BALB C; Vaccines, DNA; Viral Hepatitis Vaccines
PubMed: 34903252
DOI: 10.1186/s12985-021-01716-8 -
Journal of Hazardous Materials Mar 2022Antibiotic resistance is considered one of the biggest threats to public health and has become a major concern for governments and international organizations. Combating...
Antibiotic resistance is considered one of the biggest threats to public health and has become a major concern for governments and international organizations. Combating this problem starts with improving global surveillance of antibiotic resistance genes (ARGs) and applying standardized protocols, both in a clinical and environmental context, in agreement with the One Health approach. Exceptional efforts should be directed to controlling ARGs conferring resistance to Critically Important Antimicrobials (CIA). In this study, a systematic literature review to synthesize data on the identification of mcr genes using a PCR technique was performed. Additionally, a novel set of PCR primers for mcr-1 - mcr-9 genes detection was proposed. The developed primers were in silico and experimentally validated by comparison with mcr-specific PCR primers reported in the literature. This validation, besides being a proof-of-concept for primers' usefulness, provided insight into the distribution of mcr genes in municipal wastewater, clay and river sediments, glacier moraine, manure, seagulls and auks feces and daphnids from four countries. This analysis proved that commonly used primers may deliver false results, and some mcr genes may be overlooked in tested samples. Newly-developed PCR primers turned out to be relevant for the screening of mcr genes in various environments.
Topics: Anti-Bacterial Agents; Colistin; Drug Resistance, Bacterial; Plasmids; Polymerase Chain Reaction
PubMed: 34883371
DOI: 10.1016/j.jhazmat.2021.127936 -
Germs Dec 2020Updated and comprehensive data on the mechanism underlying colistin resistance is lacking in Africa. (Review)
Review
INTRODUCTION
Updated and comprehensive data on the mechanism underlying colistin resistance is lacking in Africa.
LITERATURE SEARCH
Herein, we aimed to review available literature on the molecular mechanisms of colistin resistance in Africa. PubMed, Google Scholar, and African Journal online databases were searched on the 15th of January 2020 for original research articles that reported mechanisms of colistin resistance in any of the 54 African countries.
REVIEW
Of the 1473 studies identified through initial database search, 36 met the inclusion criteria. Colistin resistance was mostly observed in isolated from human clinical samples. Plasmid-mediated colistin resistance mechanism (26; 72.2%) was the most frequently reported resistance mechanism. About three-quarters (27; 75.0%) of the 36 studies were done in North Africa. In this zone, the mobilized colistin resistance () genes were mostly detected in harboring three plasmid types, , , and , from animal samples (n=9; 42.8%). Of the six studies performed in Southern Africa, four reported mostly detected from human samples (n=2; 50.0%) in isolates carrying , , and with diverse range of STs. One hitherto unknown mutation, the mutation in the gene was detected in colistin resistant isolates in this region, which was absent in colistin susceptible isolates. In West and Central Africa, two and one studies, respectively, reported gene exclusively in isolates.
CONCLUSIONS
Transferable plasmid mediated colistin resistance is rapidly emerging in Africa with as the predominant genetic variant in human, animals, and environmental samples.
PubMed: 33489952
DOI: 10.18683/germs.2020.1229 -
MSystems Nov 2020Antibiotic resistance (AR) remains a major threat to public and animal health globally. However, AR ramifications in developing countries are worsened by limited...
Antibiotic resistance (AR) remains a major threat to public and animal health globally. However, AR ramifications in developing countries are worsened by limited molecular diagnostics, expensive therapeutics, inadequate numbers of skilled clinicians and scientists, and unsanitary environments. The epidemiology of Gram-negative bacteria, their AR genes, and geographical distribution in Africa are described here. Data were extracted and analyzed from English-language articles published between 2015 and December 2019. The genomes and AR genes of the various species, obtained from the Pathosystems Resource Integration Center (PATRIC) and NCBI were analyzed phylogenetically using Randomized Axelerated Maximum Likelihood (RAxML) and annotated with Figtree. The geographic location of resistant clones/clades was mapped manually. Thirty species from 31 countries and 24 genera from 41 countries were analyzed from 146 articles and 3,028 genomes, respectively. Genes mediating resistance to β-lactams (including , , , , , and ), fluoroquinolones (, , , and mutations, etc.), aminoglycosides (including and ), sulfonamides (), trimethoprim (), tetracycline [(A/B/C/D/G/O/M/39)], colistin (), phenicols (, ), and fosfomycin () were mostly found in spp. and , and also in , , , , , etc., on mostly IncF-type, IncX, ColRNAI, and IncR plasmids, within 1 gene cassettes, insertion sequences, and transposons. Clonal and multiclonal outbreaks and dissemination of resistance genes across species and countries and between humans, animals, plants, and the environment were observed; ST103, ST101, ST1/2, and ST69/515 were common strains. Most pathogens were of human origin, and zoonotic transmissions were relatively limited. Antibiotic resistance (AR) is one of the major public health threats and challenges to effective containment and treatment of infectious bacterial diseases worldwide. Here, we used different methods to map out the geographical hot spots, sources, and evolutionary epidemiology of AR. , , , , , spp., , , , etc., were common pathogens shuttling AR genes in Africa. Transmission of the same clones/strains across countries and between animals, humans, plants, and the environment was observed. We recommend spp. or as better sentinel species for AR surveillance.
PubMed: 33234606
DOI: 10.1128/mSystems.00897-20 -
Advanced Drug Delivery Reviews 2020Vaccines are one of the most powerful technologies supporting public health. The adaptive immune response induced by immunization arises following appropriate activation...
Vaccines are one of the most powerful technologies supporting public health. The adaptive immune response induced by immunization arises following appropriate activation and differentiation of T and B cells in lymph nodes. Among many parameters impacting the resulting immune response, the presence of antigen and inflammatory cues for an appropriate temporal duration within the lymph nodes, and further within appropriate subcompartments of the lymph nodes- the right timing and location- play a critical role in shaping cellular and humoral immunity. Here we review recent advances in our understanding of how vaccine kinetics and biodistribution impact adaptive immunity, and the underlying immunological mechanisms that govern these responses. We discuss emerging approaches to engineer these properties for future vaccines, with a focus on subunit vaccines.
Topics: Adjuvants, Immunologic; B-Lymphocytes; Drug Carriers; Humans; Immunity, Humoral; Inflammation Mediators; Liposomes; Lymph Nodes; Nanoparticles; Plasmids; RNA, Messenger; T-Lymphocytes; Tissue Distribution; Vaccines
PubMed: 32598970
DOI: 10.1016/j.addr.2020.06.019