Diarrheal Outbreaks Research Articles

Genome Sequence for Shiga Toxin-Producing Escherichia coli O26:H11, Associated with a Cluster of Hemolytic-Uremic Syndrome Cases in South Africa, 2017.

ABSTRACTShiga toxin-producing Escherichia coli (STEC) strains are primarily foodborne pathogens that may cause diarrheal outbreaks and are associated with severe complications, specifically hemolytic-uremic syndrome (HUS). We report here genome sequence data for STEC O26:H11, which is associated with a cluster of cases of HUS, a rarely described syndrome in South Africa.

Occurrence of Vibrio cholerae in water reservoirs of Burkina Faso

Africa is currently an important region in which cholera epidemics occur. Little is known about the presence of Vibrio cholerae in freshwater bodies in Africa. There are ca. 1700 lakes and reservoirs in Burkina Faso, most of which have been built within recent decades to secure water resources. The purpose of this study was to investigate the presence of V. cholerae in the water of reservoirs, using the most-probable-number polymerase chain reaction. Results showed that V. cholerae could be detected in water samples collected from 14 of 39 sampled reservoirs. The concentrations varied from 0 MPN/l to more than 1100 MPN/l. Fifty strains of V. cholerae isolated on CHROMagar™ vibrio were identified as V. cholerae non-O1/non-O139, none of which carried the ctxA gene.A significant positive correlation was found between the presence of V. cholerae in the reservoirs and both alkaline pH and phytoplankton biomass. V. cholerae was present in significantly higher numbers in reservoirs of urban areas than in rural areas. Since V. cholerae non-O1/non-O139 has been shown to be a causative agent of endemic diarrheal outbreaks, their presence in Burkina Faso reservoirs suggests they may play a role in gastroenteritis in that country.

Characterization of diarrheagenic E. coli causing a diarrheal outbreak in the south of Iran, Summer 2015

Characterization of diarrheagenic E. coli causing a diarrheal outbreak in the south of Iran, Summer 2015

Outbreak investigation of acute diarrheal disease in Palitana urban, Gujarat

Background: Clustering of diarrhoea and vomiting cases were reported in Palitana urban on 22 December 2014. Rapid response team was sent from government medical college, Bhavnagar to control the epidemic. Methods: A cross sectional study was conducted in Palitana urban for acute diarrheal disease epidemic investigation. Secondary data obtained from health staff and analysed to have clear picture of epidemic. Necessary actions were taken to control it. Results: Total 390 cases were reported. Out of them 21-30 adult age group was more affected as compared to other age groups. Attack rate of diarrheal disease was more in male population (85.61%) as compared to female population (40.99%).Over all attack rate was 64.19%. Conclusions: It was an acute diarrheal disease outbreak due to mixing of drinking water with polluted water.

Five years annual report on neonatal diarrheal outbreaks in Yogyakarta.

To prevent the morbidity and mortality of diarrhea in neonatal nursery units, especially in developing oountries, we suggest 3 points to be considered :a) planning of bed capacities according to the need of the surrounding area;b) prompt investigation of the best ratio between babies and nurses to guarantee the best nursing care (Walsh, 1971);c) nurse retraining every 3-6 months.

Community Laboratory Testing for Cryptosporidium: Multicenter Study Retesting Public Health Surveillance Stool Samples Positive for Cryptosporidium by Rapid Cartridge Assay with Direct Fluorescent Antibody Testing.

Cryptosporidium is a common cause of sporadic diarrheal disease and outbreaks in the United States. Increasingly, immunochromatography-based rapid cartridge assays (RCAs) are providing community laboratories with a quick cryptosporidiosis diagnostic method. In the current study, the Centers for Disease Control and Prevention (CDC), the Association of Public Health Laboratories (APHL), and four state health departments evaluated RCA-positive samples obtained during routine Cryptosporidium testing. All samples underwent “head to head” re-testing using both RCA and direct fluorescence assay (DFA). Community level results from three sites indicated that 54.4% (166/305) of Meridian ImmunoCard STAT! positives and 87.0% (67/77) of Remel Xpect positives were confirmed by DFA. When samples were retested by RCA at state laboratories and compared with DFA, 83.3% (155/186) of Meridian ImmunoCard STAT! positives and 95.2% (60/63) of Remel Xpect positives were confirmed. The percentage of confirmed community results varied by site: Minnesota, 39.0%; New York, 63.9%; and Wisconsin, 72.1%. The percentage of confirmed community results decreased with patient age; 12.5% of community positive tests could be confirmed by DFA for patients 60 years of age or older. The percentage of confirmed results did not differ significantly by sex, storage temperature, time between sample collection and testing, or season. Findings from this study demonstrate a lower confirmation rate of community RCA positives when compared to RCA positives identified at state laboratories. Elucidating the causes of decreased test performance in order to improve overall community laboratory performance of these tests is critical for understanding the epidemiology of cryptosporidiosis in the United States (US).

Viral diarrhea in children: Time to start rapid diagnosis and vaccination

Background: Acute diarrheal diseases are the most common cause of morbidity and mortality in children under 5 years of age throughout the world. This study was done to find out the incidence of rotavirus and adenovirus infection in children below 5 years of age. Materials and Methods: A total of 105 stool samples were collected from hospitalized children below 5 years of age with diarrhea from a private children hospital and tested for rotavirus and adenovirus antigen detection by rapid immunochromatography (RICT). Results: Of the 105 patients tested, 44 (42%) were positive for rotavirus, and two (2%) were positive for adenovirus by RICT. None of the children were positive for both rotavirus and adenovirus. Out of 105 children, only two had received rotavirus vaccine. They were negative for both rotavirus and adenovirus. Conclusion: The rotavirus vaccine can be included in the Universal Immunization Programme. Although the sensitivity and specificity of RICT were reported as 75% and 95% only, it is useful to detect viral diarrhea at the point of care for effective management and containment of diarrheal outbreaks at field level.

Unexpected detection of porcine rotavirus C strains carrying human origin VP6 gene

ABSTRACTBackground: Rotavirus C (RVC), a known etiological agent of diarrheal outbreaks, mainly inflicts swine population globally with sporadic incidence in human, cattle, ferret, mink and dog.Objective: To demonstrate the presence of RVC in Indian swine population and characterization of its selected structural (VP6) and non-structural (NSP4 and NSP5) genes.Methods: A total of 108 diarrheic samples from different regions of India were used. Isolated RNA was loaded onto polyacrylamide gel to screen for the presence of RVs through the identification of specific electrophoretic genomic migration pattern. To characterize the RVC strains, VP6 gene and NSP4 and NSP5 genes were amplified, sequenced and analyzed.Results: Based on VP6 gene specific diagnostic RT-PCR, the presence of RVC was confirmed in 12.0% (13/108) piglet fecal specimens. The nucleotide sequence analysis of VP6 gene, encoding inner capsid protein, from selected porcine RVC (PoRVC) strains revealed more than 93% homologies to human RVC strains (HuRVC) of Eurasian origin. These strains were distant from hitherto reported PoRVCs and clustered with HuRVCs, owning I2 genotype. However, the two non-structural genes, i.e. NSP4 and NSP5, of these strains were found to be of swine type, signifying a re-assortment event that has occurred in the Indian swine population.Conclusion: The findings indicate the presence of human-like RVC in Indian pigs and division of RVC clade with I2 genotype into further sub-clades. To the best of our knowledge, this appears to be the first report of RVC in Indian swine population. Incidence of human-like RVC VP6 gene in swine supports its subsequent zoonotic prospective.

An Outbreak of Diarrhea in Mandera, Kenya, Due to Escherichia coli Serogroup O-Nontypable Strain That Had a Coding Gene for Enteroaggregative E. coli Heat-Stable Enterotoxin 1.

In an outbreak of gastroenteritis in December 2009, in Mandera, Kenya, Escherichia coli O-nontypable (ONT) strain was isolated from stool specimens of patients (18/24, 75%). The E. coli ONT organisms could not be assigned to any of the recognized diarrheagenic groups of E. coli However, they possessed the enteroaggregative E. coli heat-stable enterotoxin-1 gene. The cell-free culture filtrates of the E. coli ONT strain isolated from the outbreak cases induced considerable amount of fluid accumulation in suckling mouse intestine, indicating production of an enterotoxic factor(s). These results identify E. coli that did not have any diarrheagenic characteristics except astA as the etiological agent of the diarrheal outbreak in Mandera. It is however considered necessary to characterize the fluid accumulation factor(s) to determine whether any novel toxins were responsible for the fluid accumulation. Moreover, it is important to study dissemination of strains producing the enterotoxic factor(s) to assess their public health significance distribution in the environment.

Metagenomics of Two Severe Foodborne Outbreaks Provides Diagnostic Signatures and Signs of Coinfection Not Attainable by Traditional Methods.

Diagnostic testing for enteric pathogens has relied for decades on culture-based techniques, but a total of 38.4 million cases of foodborne illness per year cannot be attributed to specific causes. This study describes new culture-independent metagenomic approaches and the associated bioinformatics pipeline to detect and type the causative agents of microbial disease with unprecedented accuracy, opening new possibilities for the future development of health technologies and diagnostics. Our tools and approaches should be applicable to other microbial diseases in addition to foodborne diarrhea.

Virulence determinants in enteroaggregative Escherichia coli from North India and their interaction in in vitro organ culture system.

Enteroaggregative Escherichia coli (EAEC) is an important diarrhoeal pathogen causing diseases in multiple epidemiological and clinical settings. In developing countries like India, diarrhoeal diseases are one of the major killers among paediatric population and oddly, few studies are available from Indian paediatric population on the variability of EAEC virulence genes. In this study, we examined the distribution of plasmid and chromosomal-encoded virulence determinants in EAEC isolates, and analysed cytokines response generated against EAEC with specific aggregative adherence fimbriae (AAF) type in duodenal biopsies using in vitro organ culture (IVOC) mimicking in vivo conditions. Different virulence marker combinations among strains were reflected as a function of specific adhesins signifying EAEC heterogeneity. fis gene emerged as an important genetic marker apart from aggA and aap Further, EAEC infection in IVOC showed upregulation of IL-8, IL-1β, IL-6, TNF-α and TLR-5 expression. EAEC with AAFII induced significant TLR-5 and IL-8 response, conceivably owing to more pathogenicity markers. This study sheds light on the pattern of EAEC pathotypes prevalent in North Indian paediatric population and highlights the presence of unique virulence combinations in pathogenic strains. Thus, evident diversity in EAEC virulence and multifaceted bacteria-host crosstalk can provide useful insights for the strategic management of diarrhoeal diseases in India, where diarrhoeal outbreaks are more frequent.

Atypical enteropathogenic Escherichia coli as aetiologic agents of sporadic and outbreak-associated diarrhoea in Brazil.

Enteropathogenic Escherichia coli (EPEC) are important agents of diarrhoea in industrialized as well as developing countries, such as Brazil. The hallmark of EPEC pathogenesis is the establishment of attaching and effacing lesions in enterocytes, in which pedestal-like structures are formed underneath adherent bacteria. EPEC are divided into two subgroups, typical (tEPEC) and atypical (aEPEC), based on the presence of the EPEC adherence factor plasmid in tEPEC and its absence in aEPEC. This study was designed to characterize 82 aEPEC isolates obtained from stool samples of diarrhoeic patients during 2012 and 2013 in Brazil. The majority of the aEPEC were assigned to the phylo-group B1 (48.8 %), and intimin subtypes θ (20.7 %), β1 (9.7 %) and λ (9.7 %) were the most prevalent among the isolates. The nleB and nleE genes were concomitantly detected in 32.9 % of the isolates, demonstrating the occurrence of the pathogenicity island O122 among them. The O157-plasmid genes (ehxA and/or espP) were detected in 7.3 % of the isolates, suggesting that some aEPEC could be derived from Shiga-toxin-producing E. coli that lost the stx genes while trafficking in the host. PFGE of 14 aEPEC of serotypes O2 : H16, O33 : H34, O39 : H9, O108 : H- and ONT : H19 isolated from five distinct outbreaks showed serotype-specific PFGE clusters, indicating a high degree of similarity among the isolates from the same event, thus highlighting these serotypes as potential aetiologic agents of diarrhoeal outbreaks in Brazil.

Epidemiology of Cryptosporidiosis and Giardiasis: What Pediatricians Need to Know

Diarrheal illness in the USA is a significant contributor to adverse morbidity in children and has a major impact economically, including the utilization of healthcare resources. Viral and bacterial pathogens account for the majority of cases that have an infectious cause; however, intestinal protozoan parasites are important but often under-recognized etiologic agents for infectious diarrhea. Cryptosporidium spp. and Giardia lamblia are the most common intestinal protozoal infections in both resource-limited and resource-abundant countries and predominately affect children, usually those between ages 1–9 years and most often in children less than 4 years of age. Both Cryptosporidium and Giardia are ubiquitous in the environment and transmit primarily through the fecal-oral route after ingestion of oocysts/cysts in contaminated water or food or direct person-to-person contact. Both are environmentally hardy. The chlorine-tolerant Cryptosporidium oocysts in particular have led to more diarrheal outbreaks due to treated recreational water exposure than any other pathogen. Despite notifiable diseases in the USA, reporting is very low and thus general awareness of epidemiology and clinical manifestations is limited. Underdiagnosis can further contribute to under-reporting, especially in asymptomatic patients and where specialty consultation and reliable diagnostics are absent. Once a diagnosis of cryptosporidiosis or giardiasis has been confirmed, in addition to appropriate case reporting and treatment considerations, it is essential to provide educational support to children and their parents or caregivers to prevent further transmission of the disease within the household and throughout the community.

Intraosseous vascular access in disasters and mass casualty events: A review of the literature.

The intraosseous (IO) route of vascular access has been increasingly used to administer resuscitative fluids and drugs to patients in whom reliable intravenous (IV) access could not be rapidly or easily obtained. It is unknown that to what extent the IO route has been used to gain vascular access during disasters and mass casualty events. The purpose of this review was to examine the existing literature to answer the research question, "What is the utility of the IO route compared to other routes for establishing vascular access in patients resulting from disasters and mass casualty events?" Keyword-based online database search of PubMed, CINAHL, and the Cochrane Database of Systematic Reviews. University-based academic research cell. Included evidence were randomized and nonrandomized trials, systematic reviews with and without meta-analysis, case series, and case reports. Excluded evidence included narrative reviews and expert opinion. Not applicable. Of 297 evidence sources located, 22 met inclusion criteria. Located evidence was organized into four categories including chemical agent poisoning, IO placement, while wearing chemical protective clothing (PPE), military trauma, and infectious disease outbreak. Evidence indicates that the IO route of infusion is pharmacokinetically equal to the IV route and superior to the intramuscular (IM) and endotracheal routes for the administration of antidotal drugs in animal models of chemical agent poisoning while wearing full chemical PPE. The IO route is superior to the IM route for antidote administration during hypovolemic shock. Civilian casualties of explosive attacks and mass shootings would likely benefit from expanded use of the IO route and military resuscitation strategies. The IO route is useful for fluid resuscitation in the management of diarrheal and hemorrhagic infectious disease outbreaks.

Multidrug-Resistant Bacteria Isolated from Surface Water in Bassaseachic Falls National Park, Mexico.

Bacterial pathogens are a leading cause of waterborne disease, and may result in gastrointestinal outbreaks worldwide. Inhabitants of the Bassaseachic Falls National Park in Chihuahua, Mexico show seasonal gastroenteritis problems. This aim of this study was to detect enteropathogenic microorganisms responsible for diarrheal outbreaks in this area. In 2013, 49 surface water samples from 13 selected sampling sites along the Basaseachi waterfall and its main rivers, were collected during the spring, summer, autumn, and winter seasons. Fecal and total coliform counts were determined using standard methods; the AutoScan-4 system was used for identification of isolates and the antibiotic resistance profile by challenging each organism using 21 antibiotics. Significant differences among seasons were detected, where autumn samples resulted in the highest total (p < 0.05) and fecal (p < 0.001) coliform counts, whereas the lowest total coliform counts were recorded in spring. Significant differences between sampling sites were observed, where samples from sites 6, 8, and 11 had the highest total coliform counts (p < 0.009), whereas samples from site 9 exhibited the lowest one. From the microbiological analysis, 33 bacterial isolates from 13 different sites and four sampling seasons were selected; 53% of isolates were resistant to at least one antibiotic, and 15% exhibited a multidrug resistance (MDB) phenotype. MDB were identified as Klebsiella oxytoca (two out of four identified isolates), Escherichia coli (2/7), and Enterobacter cloacae (1/3). In addition, some water-borne microorganisms exhibited resistance to cefazoline, cefuroxime, ampicillin, and ampicillin-sulbactam. The presence of these microorganisms near rural settlements suggests that wastewater is the contamination source, providing one possible transmission mechanism for diarrheal outbreaks.

An acute gastroenteritis outbreak caused by GII.17 norovirus in Jiangsu Province, China.

Noroviruses are a common cause of acute gastroenteritis around the world; however, reports of outbreaks caused by GII.17 norovirus are rare. An outbreak caused by GII.17 norovirus in a senior high school in Wuxi, Jiangsu Province, China is reported here. An epidemiological investigation, pathogen detection, and case-control study were performed. Epidemiological data combined with the epidemic curve indicated that this outbreak was a point source type initially, followed by secondary transmission. The first case was identified as most likely the source of the outbreak. Risk analysis showed exposure to patients and sharing a communal water cooler to be associated with the spread of infection. Sequence analysis of GII-positive samples confirmed that the norovirus GII.17 variant was the etiological agent of this outbreak.

Increased Rotavirus Prevalence in Diarrheal Outbreak Precipitated by Localized Flooding, Solomon Islands, 2014.

Flooding on 1 of the Solomon Islands precipitated a nationwide epidemic of diarrhea that spread to regions unaffected by flooding and caused >6,000 cases and 27 deaths. Rotavirus was identified in 38% of case-patients tested in the city with the most flooding. Outbreak potential related to weather reinforces the need for global rotavirus vaccination.

Investigation of a suspected diarrhoeal illness outbreak in Upington – ZF Mgcawu District, Northern Cape, South Africa, March – July 2015

Investigation of a suspected diarrhoeal illness outbreak in Upington – ZF Mgcawu District, Northern Cape, South Africa, March – July 2015

Genetic analyses of GII.17 norovirus strains in diarrheal disease outbreaks from December 2014 to March 2015 in Japan reveal a novel polymerase sequence and amino acid substitutions in the capsid region.

A novel GII.P17-GII.17 variant norovirus emerged as a major cause of norovirus outbreaks from December 2014 to March 2015 in Japan. Named Hu/GII/JP/2014/GII.P17-GII.17, this variant has a newly identified GII.P17 type RNA-dependent RNA polymerase, while the capsid sequence displays amino acid substitutions around histo-blood group antigen (HBGA) binding sites. Several variants caused by mutations in the capsid region have previously been observed in the GII.4 genotype. Monitoring the GII.17 variant's geographical spread and evolution is important.

Secular trends in 1,192 diarrheal outbreaks in the Israel Defence Forces between 1988-2011.

BackgroundIn the military, outbreaks of infectious diarrhea pose a significant health problem. In this descriptive analysis of data collected by the IDF on all infectious diarrhea outbreaks between 1988–2011, we analysed temporal, seasonal, and unit-type trends in 1,192 diarrheal outbreaks in the Israel Defence Forces (IDF) over a 24-year period, and described the long-term trends in seasonality and the effects of strategic preventive measures on outbreak frequency among populations at risk.ResultsWe found two distinct phases in annual outbreak occurrence. The mean annual number of outbreaks during the period 1988–1996 was 75.8 (±14.50) but dropped to 34.0 (±8.13) during the period 1997–2011 (P < 0.0001). Overall, a downward trend continued through the 1990’s, while from 2000 onwards outbreak counts fluctuated annually. A significantly higher number of outbreaks occurred during the summer season, throughout the study period. The greatest number of outbreaks occurred in deployed units, although the proportion of outbreaks in this unit type decreased over time. Accordingly, the proportion of outbreaks in training units more than doubled during the study window. When we looked at outbreak size, summer outbreaks increased in magnitude over time, and during all periods outbreaks were larger, on average, in training units than in deployed units.ConclusionsThe changing patterns in diarrheal outbreaks in the Israel Defence Forces require maintenance of a higher level of vigilance than ever before. Lack of a clear peak period require the use of all available preventive measures throughout the year. This is especially true in training units, where the increased number of outbreaks coincides with increased trainee volume, regardless of season.