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Current Opinion in Infectious Diseases Oct 2018Diarrhoea is a major global health problem, and recent studies have confirmed Shigella as a major contributor to this burden. Here, we review recent advances in Shigella... (Review)
Review
PURPOSE OF REVIEW
Diarrhoea is a major global health problem, and recent studies have confirmed Shigella as a major contributor to this burden. Here, we review recent advances in Shigella research; focusing on their epidemiology, pathogenesis, antimicrobial resistance, and the role of the gut microbiome during infection.
RECENT FINDINGS
Enhanced epidemiological data, combined with new generation diagnostics, has highlighted a greater burden of Shigella disease than was previously estimated, which is not restricted to vulnerable populations in low-middle income countries. As we gain an ever more detailed insight into the orchestrated mechanisms that Shigella exploit to trigger infection, we can also begin to appreciate the complex role of the gut microbiome in preventing and inducing such infections. The use of genomics, in combination with epidemiological data and laboratory investigations, has unravelled the evolution and spread of various species. Such measures have identified resistance to antimicrobials as a key contributor to the success of specific clones.
SUMMARY
We need to apply novel findings towards sustainable approaches for treating and preventing Shigella infections. Vaccines and alternative treatments are under development and may offer an opportunity to reduce the burden of Shigella disease and restrict the mobility of antimicrobial resistant clones.
Topics: Anti-Bacterial Agents; Antibiosis; Communicable Disease Control; Diarrhea; Dysentery, Bacillary; Gastrointestinal Microbiome; Global Health; Humans; Shigella; Shigella Vaccines
PubMed: 30048255
DOI: 10.1097/QCO.0000000000000475 -
Microbiology Spectrum Mar 2019is a genus of Gram-negative enteropathogens that have long been, and continue to be, an important public health concern worldwide. Over the past several decades, spp.... (Review)
Review
is a genus of Gram-negative enteropathogens that have long been, and continue to be, an important public health concern worldwide. Over the past several decades, spp. have also served as model pathogens in the study of bacterial pathogenesis, and has become one of the best-studied pathogens on a molecular, cellular, and tissue level. In the arms race between and the host immune system, has developed highly sophisticated mechanisms to subvert host cell processes in order to promote infection, escape immune detection, and prevent bacterial clearance. Here, we give an overview of pathogenesis while highlighting innovative techniques and methods whose application has significantly advanced our understanding of pathogenesis in recent years.
Topics: Adaptive Immunity; Adhesins, Bacterial; Bacterial Proteins; Cytosol; Dysentery, Bacillary; Epithelial Cells; Gastrointestinal Microbiome; Host-Pathogen Interactions; Humans; Immune Evasion; Shigella; Shigella flexneri; Type III Secretion Systems; Virulence; Virulence Factors
PubMed: 30953429
DOI: 10.1128/microbiolspec.BAI-0023-2019 -
Archives of Microbiology Jan 2021Shigella sonnei is the emerging pathogen globally, as it is the second common infectious species of shigellosis (bloody diarrhoea) in low- and middle-income countries... (Review)
Review
Shigella sonnei is the emerging pathogen globally, as it is the second common infectious species of shigellosis (bloody diarrhoea) in low- and middle-income countries (LMICs) and the leading one in developed world. The multifactorial processes and novel mechanisms have been identified in S. sonnei, that are collectively playing apart a substantial role in increasing its prevalence, while replacing the S. flexneri and other Gram-negative gut pathogens niche occupancy. Recently, studies suggest that due to improvement in sanitation S. sonnei has reduced cross-immunization from Plesiomonas shigelliodes (having same O-antigen as S. sonnei) and also found to outcompete the two major species of Enterobacteriaceae family (Shigella flexneri and Escherichia coli), due to encoding of type VI secretion system (T6SS). This review aimed to highlight S. sonnei as an emerging pathogen in the light of recent research with pondering aspects on its epidemiology, transmission, and pathogenic mechanisms. Additionally, this paper aimed to review S. sonnei disease pattern and related complications, symptoms, and laboratory diagnostic techniques. Furthermore, the available treatment reigns and antibiotic-resistance patterns of S. sonnei are also discussed, as the ciprofloxacin and fluoroquinolone-resistant S. sonnei has already intensified the global spread and burden of antimicrobial resistance. In last, prevention and controlling strategies are briefed to limit and tackle S. sonnei and possible future areas are also explored that needed more research to unravel the hidden mysteries surrounding S. sonnei.
Topics: Anti-Bacterial Agents; Ciprofloxacin; Drug Resistance, Bacterial; Dysentery, Bacillary; Escherichia coli; Fluoroquinolones; Humans; Shigella flexneri; Shigella sonnei; Type VI Secretion Systems
PubMed: 32929595
DOI: 10.1007/s00203-020-02034-3 -
EcoSal Plus Jan 2018The history of , the causative agent of bacillary dysentery, is a long and fascinating one. This brief historical account starts with descriptions of the disease and its... (Review)
Review
The history of , the causative agent of bacillary dysentery, is a long and fascinating one. This brief historical account starts with descriptions of the disease and its impact on human health from ancient time to the present. Our story of the bacterium starts just before the identification of the dysentery bacillus by Kiyoshi Shiga in 1898 and follows the scientific discoveries and principal scientists who contributed to the elucidation of pathogenesis in the first 100 years. Over the past century, has proved to be an outstanding model of an invasive bacterial pathogen and has served as a paradigm for the study of other bacterial pathogens. In addition to invasion of epithelial cells, some of those shared virulence traits include toxin production, multiple-antibiotic resistance, virulence genes encoded on plasmids and bacteriophages, global regulation of virulence genes, pathogenicity islands, intracellular motility, remodeling of host cytoskeleton, inflammation/polymorphonuclear leukocyte signaling, apoptosis induction/inhibition, and "black holes" and antivirulence genes. While there is still much to learn from studying pathogenesis, what we have learned so far has also contributed greatly to our broader understanding of bacterial pathogenesis.
Topics: Animals; Bacteriophages; Disease Models, Animal; Dysentery, Bacillary; Epithelial Cells; Genes, Bacterial; Genomic Islands; History, 19th Century; History, 20th Century; Host-Pathogen Interactions; Humans; Mice; Plasmids; Shigella; Virulence; Virulence Factors
PubMed: 29318984
DOI: 10.1128/ecosalplus.ESP-0006-2017 -
Jornal de Pediatria 2020To restate the epidemiological importance of Shigella in acute diarrhea with blood, providing an overview of the treatment and stressing the need for the correct... (Review)
Review
OBJECTIVE
To restate the epidemiological importance of Shigella in acute diarrhea with blood, providing an overview of the treatment and stressing the need for the correct indication of antibiotic therapy.
SOURCES OF DATA
A search was carried out in the Medline and Scopus databases, in addition to the World Health Organization scientific documents and guidelines, identifying review articles and original articles considered relevant to substantiate the narrative review.
SYNTHESIS OF DATA
Different pathogens have been associated with acute diarrhea with blood; Shigella was the most frequently identified. The manifestations of shigellosis in healthy individuals are usually of moderate intensity and disappear within a few days. There may be progression to overt dysentery with blood and mucus, lower abdominal pain, and tenesmus. Conventional bacterial stool culture is the gold standard for the etiological diagnosis; however, new molecular tests have been developed to allow the physician to initiate targeted antibacterial treatment, addressing a major current concern caused by the increasing resistance of Shigella. Prevention strategies include breastfeeding, hygiene measures, health education, water treatment, and the potential use of vaccines.
CONCLUSIONS
Acute diarrhea is an important cause of mortality in children under 5 years and shigellosis is the leading cause of acute diarrhea with blood worldwide. The current concern is the increase in microbial resistance to the recommended antibiotics, which brings an additional difficulty to therapeutic management. Although no vaccine is yet available against Shigella, several candidates are undergoing clinical trials, and this may be the most cost-effective preventative measure in future.
Topics: Diarrhea; Dysentery, Bacillary; Feces; Humans; Pharmaceutical Preparations; Shigella
PubMed: 31604059
DOI: 10.1016/j.jped.2019.08.006 -
Vaccine Aug 2019
Topics: Animals; Congresses as Topic; Dysentery, Bacillary; Enterotoxigenic Escherichia coli; Escherichia coli Infections; Escherichia coli Vaccines; Humans; Immunization; Mexico; Shigella; Shigella Vaccines
PubMed: 31300286
DOI: 10.1016/j.vaccine.2019.06.085 -
Clinics in Laboratory Medicine Jun 2015Salmonella, Shigella, and Yersinia cause a well-characterized spectrum of disease in humans, ranging from asymptomatic carriage to hemorrhagic colitis and fatal... (Review)
Review
Salmonella, Shigella, and Yersinia cause a well-characterized spectrum of disease in humans, ranging from asymptomatic carriage to hemorrhagic colitis and fatal typhoidal fever. These pathogens are responsible for millions of cases of food-borne illness in the United States each year, with substantial costs measured in hospitalizations and lost productivity. In the developing world, illness caused by these pathogens is not only more prevalent but also associated with a greater case-fatality rate. Classic methods for identification rely on selective media and serology, but newer methods based on mass spectrometry and polymerase chain reaction show great promise for routine clinical testing.
Topics: Bacteriological Techniques; Classification; Dysentery, Bacillary; Humans; Microbial Sensitivity Tests; Salmonella; Salmonella Infections; Shigella; Specimen Handling; Yersinia; Yersinia Infections
PubMed: 26004640
DOI: 10.1016/j.cll.2015.02.002 -
Journal of Microbiology (Seoul, Korea) Apr 2005Shigellosis is a global human health problem. Four species of Shigella i.e. S. dysenteriae, S. flexneri, S. boydii and S. sonnei are able to cause the disease. These... (Review)
Review
Shigellosis is a global human health problem. Four species of Shigella i.e. S. dysenteriae, S. flexneri, S. boydii and S. sonnei are able to cause the disease. These species are subdivided into serotypes on the basis of O-specific polysaccharide of the LPS. Shigella dysenteriae type 1 produces severe disease and may be associated with life-threatening complications. The symptoms of shigellosis include diarrhoea and/or dysentery with frequent mucoid bloody stools, abdominal cramps and tenesmus. Shigella spp. cause dysentery by invading the colonic mucosa. Shigella bacteria multiply within colonic epithelial cells, cause cell death and spread laterally to infect and kill adjacent epithelial cells, causing mucosal ulceration, inflammation and bleeding. Transmission usually occurs via contaminated food and water or through person-to-person contact. Laboratory diagnosis is made by culturing the stool samples using selective/differential agar media. Shigella spp. are highly fragile organism and considerable care must be exercised in collecting faecal specimens, transporting them to the laboratories and in using appropriate media for isolation. Antimicrobial agents are the mainstay of therapy of all cases of shigellosis. Due to the global emergence of drug resistance, the choice of antimicrobial agents for treating shigellosis is limited. Although single dose of norfloxacin and ciprofloxacin has been shown to be effective, they are currently less effective against S. dysenteriae type 1 infection. Newer quinolones, cephalosporin derivatives, and azithromycin are the drug of choice. However, fluoroquinolone-resistant S. dysenteriae type 1 infection have been reported. Currently, no vaccines against Shigella infection exist. Both live and subunit parenteral vaccine candidates are under development. Because immunity to Shigella is serotype-specific, the priority is to develop vaccine against S. dysenteriae type 1 and S. flexneri type 2a. Shigella species are important pathogens responsible for diarrhoeal diseases and dysentery occurring all over the world. The morbidity and mortality due to shigellosis are especially high among children in developing countries. A recent review of literature (Kotloff et al.,1999) concluded that, of the estimated 165 million cases of Shigella diarrhoea that occur annually, 99% occur in developing countries, and in developing countries 69% of episodes occur in children under five years of age. Moreover, of the ca.1.1 million deaths attributed to Shigella infections in developing countries, 60% of deaths occur in the under-five age group. Travellers from developed to developing regions and soldiers serving under field conditions are also at an increased risk to develop shigellosis.
Topics: Drug Resistance, Bacterial; Dysentery, Bacillary; Humans; Shigella; Shigella Vaccines; Virulence Factors
PubMed: 15880088
DOI: No ID Found -
Trends in Microbiology Aug 2020
Topics: Dysentery, Bacillary; Genome, Bacterial; Humans; Shigella sonnei; Type III Secretion Systems; Type VI Secretion Systems
PubMed: 32663462
DOI: 10.1016/j.tim.2020.02.011 -
Virulence Dec 2023spp. are the causative agent of shigellosis (or bacillary dysentery), a diarrhoeal disease characterized for the bacterial invasion of gut epithelial cells. Among the 4... (Review)
Review
spp. are the causative agent of shigellosis (or bacillary dysentery), a diarrhoeal disease characterized for the bacterial invasion of gut epithelial cells. Among the 4 species included in the genus, is principally responsible for the disease in the developing world while is the main causative agent in high-income countries. Remarkably, as more countries improve their socioeconomic conditions, we observe an increase in the relative prevalence of . To date, the reasons behind this change in aetiology depending on economic growth are not understood. has been widely used as a model to study the pathogenesis of the genus, but as more research data are collected, important discrepancies with have come to light. In comparison to can be differentiated in numerous aspects; it presents a characteristic O-antigen identical to that of one serogroup of the environmental bacterium , a group 4 capsule, antibacterial mechanisms to outcompete and displace gut commensal bacteria, and a poorer adaptation to an intracellular lifestyle. In addition, the World Health Organization (WHO) have recognized the significant threat posed by antibiotic-resistant strains of , demanding new approaches. This review gathers knowledge on what is known about within the context of other spp. and aims to open the door for future research on understanding the increasing spread of this pathogen.
Topics: Humans; Shigella sonnei; Virulence; Prevalence; Anti-Bacterial Agents; Cell Differentiation; Dysentery, Bacillary
PubMed: 37994877
DOI: 10.1080/21505594.2023.2280838