Diarrheal Outbreaks Research Articles

Surveillance of Food and Waterborne Pathogens in North-East India: Protocol for a Laboratory-Based Sentinel Surveillance Study.

Food safety is a global concern, which is often underestimated owing to challenges in investigating foodborne diseases. These challenges arise from the increased globalization of the food trade, advancements in agricultural practices, and shifts in environmental factors. In North-East India, common diarrheal outbreaks from fermented foods pose significant health risks. Despite these challenges, systematic data on foodborne pathogens is lacking in India, highlighting a crucial gap in understanding food safety issues. The aim of this research protocol is to establish an integrated surveillance system to identify enteric pathogens circulating within humans, food animals, and the environment through a health approach in North-East India, and to conduct outbreak investigations. The Indian Council of Medical Research (ICMR) initiated a surveillance study across all 8 North-East states in India, employing a centralized digital database for data collation. The project aims to enhance theinfrastructure for microbial culture, antibiotic sensitivity testing, and molecular epidemiological studies. The study involves laboratory-based surveillance of foodborne pathogens in market foods, hospitalized diarrheal patients, poultry and animal farms, slaughterhouses, butcher shops, and diarrheal outbreaks. A standardized case report form ensures consistent data collection of age, sex, signs, symptoms, and admission dates for diarrheal cases. Stool and rectal swabs will undergo testing for pathogen identification and antimicrobial resistance. Similarly, samples of market foods, food animals, and the environment will be collected. Outbreaks confirmed by the Integrated Disease Surveillance Project (IDSP) will be thoroughly investigated following standardized guidelines. In phase I, 5 surveillance centers were established across 4 states (ie, Assam [Dibrugarh and Guwahati], Tripura, Sikkim, and Arunachal Pradesh) in 2020. Following an interim phase I data assessment and the successful establishment of a streamlined system for data procurement, investigation, recording, and analysis, along with the implementation of regular training and monitoring programs, phase II expansion was initiated in 2023-24. This includes the addition of 7 more centers (including 3 veterinary centers) in the remaining 4 states (ie, Manipur, Meghalaya, Mizoram, and Nagaland), eventually covering the entire North-Eastern Region of India. Food and waterborne diseases are a constant public health problem in many countries. Key challenges to the enhancement of food safety policy include the paucity of systematic data and awareness. With this background, ICMR's initiative is the first systematic surveillance study in the country to adopt a single health approach. Data obtained from this project will help to understand the risk of acquiring food and waterborne pathogens, their transmission pathways, and antimicrobial resistance patterns. The scientific evidence generated through this project will be helpful in formulating and strengthening food safety policy and in initiating government programs to protect the health of the nation. DERR1-10.2196/56469.

Characteristics of Enterohaemorrhagic Escherichia coli in Jeju Province, Korea: a study of registry routes from 2017 to 2023

Enterohemorrhagic Escherichia coli (EHEC) produces Shiga toxin, which causes diarrhea, hemorrhagic colitis, and hemorrhagic uremic syndrome. The Korea Center for Disease Control and Prevention (KCDC) has designated EHEC as a legal infectious disease and has conducted laboratory surveillance. This study aimed to compare the demographic, epidemiological, clinical, and laboratory characteristics of EHEC cases in Jeju Province between August 2017 and November 2023, notified by two registry routes. The data were sourced from the integrated disease health and health management system managed by the KCDC. Cases reported due to experiencing gastrointestinal symptoms, or contacts of each case were defined as the “symptomatic” group. In contrast, cases with positive findings during a health checkup or laboratory surveillance were defined as the “screening” group. The symptomatic and screening groups had 35 and eight patients, respectively. There were significant differences in the age and seasonal distribution. The selection group was 20-59 years old in the main age distribution and registered evenly throughout the four seasons. In comparison, the symptomatic group was younger or older and not registered in the winter. These findings may be used to establish a more appropriate surveillance system for diarrheal outbreaks.

An outbreak of acute diarrhoeal disease caused by Shigella sonnei in a village in Dibrugarh district, Assam.

Background & objectives Food and waterborne illnesses remain a neglected public health issue in India. Events with large gatherings frequently witness outbreaks of acute diarrheal diseases due to consumption of contaminated food or water or poor food handling practices. In the present study, an outbreak of acute diarrhoeal disease (ADD) occurring among the attendees of a birthday party in rural Dibrugarh district in the northeastern Indian State of Assam was investigated. Methods Sociodemographic information along with details of ADD outbreak that included information about source of foods, food handlers, illness details, etc., were collected using an outbreak investigation form for descriptive and analytical epidemiology. Rectal swabs from affected individuals and food handlers were collected along with bore-well water samples and tested in the laboratory by performing bacterial culture, biochemical analysis and polymerase chain reaction. Due to the delayed report on the outbreak, collecting leftover food for laboratory testing and analysis was impossible. Results A total of 25 cases of ADD had similar signs and symptoms. The mean incubation period for developing acute diarrhoea was 26.36±8.76 (± standard deviation) hours from food consumption. The overall attack rate was 60.04 per cent (25/41); 20 per cent (5/25) required hospitalization. Thirteen rectal swab samples were tested for pathogens and found positive for Shigella sonnei. Antibiotic susceptibility test of isolated S. sonnei showed resistance to nalidixic acid, ciprofloxacin and cefotaxime. Consumption of one of the food items - chicken curry was significantly associated with illness (Odds Ratio=14.8; 95% Confidence Interval: 2.75-85.11); P value<0.05 and Population Attributable Fraction (PAF) was 70.18 per cent. The water samples were found satisfactory for human consumption. Interpretation & conclusions The findings suggested that S. sonnei infection could be implicated in the investigated food-borne diarrhoeal disease outbreak and that there was a potential for human-poultry cross-infection. Additionally, the study revealed concerning levels of S. sonnei resistance to recommended antibiotics and drew attention to their public health relevance.

Domesticated animal reservoirs of Cryptosporidium and Giardia in agricultural farms in Laguna and Quezon provinces, Philippines.

Cryptosporidium and Giardia are recognized as significant etiological agents of diarrheal outbreaks in humans as these parasites may be transmitted through the ingestion of water and food contaminated with feces of human or animal origin. However, surveillance studies on the role of animal reservoirs in the transmission of Cryptosporidium and Giardia are deemed insufficient and the complete dimension of the problem contributing to contamination in an agricultural setting is unknown. This study aimed to assess the presence of Cryptosporidium and Giardia in domesticated animals from selected farms in the agricultural provinces of Laguna and Quezon in Southern Luzon, Philippines. Using immunofluorescence assay, an overall 85.7% incidence of protozoan infection was recorded among the animals (N = 161). Of these, 77.0 and 73.9% were positive for Cryptosporidium and Giardia, respectively. Highest incidence (95.83%) of Cryptosporidium was documented in swine and the highest incidence (89.47%) of Giardia was observed in ruminants. Analyses revealed significant differences in the incidence of the protozoan parasites among animals with different containment status, water source, age group, and sex. On the other hand, farm workers' knowledge on parasite transmission was negatively correlated (p = 0.001) to parasite incidence. With the scarcity of data about Cryptosporidium and Giardia in farm-raised animals in the Philippines, the information obtained from this study will be vital for protozoan source tracking and further control interventions against Cryptosporidium and Giardia infections.

Evaluation of different genomic regions of rotavirus B and rotavirus C for development of real-time RT‒PCR assays

BackgroundThe causative agents of diarrhea, rotavirus B (RVB) and rotavirus C (RVC) are common in adults and patients of all age groups, respectively. Due to the Rotavirus A (RVA) vaccination program, a significant decrease in the number of gastroenteritis cases has been observed globally. The replacement of RVA infections with RVB, RVC, or other related serogroups is suspected due to the possibility of reducing natural selective constraints due to RVA infections. The data available on RVB and RVC incidence are scant due to the lack of cheap and rapid commercial diagnostic assays and the focus on RVA infections. The present study aimed to develop real-time RT‒PCR assays using the data from all genomic RNA segments of human RVB and RVC strains available in the Gene Bank.ResultsAmong the 11 gene segments, NSP3 and NSP5 of RVB and the VP6 gene of RVC were found to be suitable for real-time RT‒PCR (qRT‒PCR) assays. Fecal specimens collected from diarrheal patients were tested simultaneously for the presence of RVB (n = 192) and RVC (n = 188) using the respective conventional RT‒PCR and newly developed qRT‒PCR assays. All RVB- and RVC-positive specimens were reactive in their respective qRT‒PCR assays and had Ct values ranging between 23.69 and 41.97 and 11.49 and 36.05, respectively. All known positive and negative specimens for other viral agents were nonreactive, and comparative analysis showed 100% concordance with conventional RT‒PCR assays.ConclusionsThe suitability of the NSP5 gene of RVB and the VP6 gene of RVC was verified via qRT‒PCR assays, which showed 100% sensitivity and specificity. The rapid qRT‒PCR assays developed will be useful diagnostic tools, especially during diarrheal outbreaks for testing non-RVA rotaviral agents and reducing the unnecessary use of antibiotics.

Sequence-subtype association of multi-drug-resistant diarrheagenic Escherichia coli

Background and Objectives: Multi-drug-resistant pathogens pose a significant threat as they can rapidly spread, leading to severe healthcare-associated invasive infections. In developing countries, diarrheagenic Escherichia coli (DEC) is a major bacterial pathogen responsible for causing diarrhea. However, the outbreak of resistant strains has made the treatment of DEC infections much more challenging. This study aimed to investigate the relationship between antibiotic resistance genes and other virulence categories in E. coli strains that cause diarrhea, particularly DEC. Materials and Methods: The phylogenetic grouping was defined using PCR and multi-locus sequence type (MLST) meth- ods. Results: Among the isolates analyzed, 14 were identified as resistant and were classified into eight distinct sequence types: ST3, ST53, ST77, ST483, ST512, ST636, ST833, and ST774, indicating genetic diversity among the resistant strains. Certain sequence types, notably ST512 and ST636, were found to be associated with multiple antibiotic resistance in DEC. Regard- ing antibiotic susceptibility, strains showed the highest resistance to amoxicillin, suggesting that this antibiotic may not be effective in treating DEC infections. On the other hand, the isolates demonstrated susceptibility to amikacin and chloram- phenicol, implying that these antibiotics could be more suitable treatment options for DEC infections. Conclusion: The findings underscore the importance of promptly identifying antibiotic resistance patterns and their correla- tion with specific pathogenic virulence categories, as this knowledge can aid in selecting the most appropriate antibiotics for treating DEC infections. Considering the antibiotic resistance profiles and associated resistance genes is crucial in managing and containing diarrheal outbreaks and in selecting effective antibiotic therapies for DEC infections.

Genomic characteristics of clinical non-toxigenic Vibrio cholerae isolates in Switzerland: a cross-sectional study.

Although non-toxigenicVibrio choleraelack thectxABgenes encoding cholera toxin, they can cause diarrhoeal disease and outbreaks in humans. In Switzerland,V. choleraeis a notifiable pathogen and all clinical isolates are analysed at the National Reference Laboratory for Enteropathogenic Bacteria and Listeria. Up to 20 infections are reported annually. In this study, we investigated the population structure and genetic characteristics of non-toxigenicV. choleraeisolates collected over five years. V. choleraeisolates were serotyped and non-toxigenic isolates identified using actxA-specific PCR. Following Illumina whole-genome sequencing, genome assemblies were screened for virulence and antibiotic resistance genes. Phylogenetic analyses were performed in the context of 965 publicly availableV. choleraegenomes. Out of 33V. choleraeinfections reported between January 2017 and January 2022 in Switzerland, 31 were caused byctxA-negative isolates. These non-toxigenic isolates originated from gastrointestinal (n = 29) or extraintestinal (n = 2) sites. They were phylogenetically diverse and belonged to 29 distinct sequence types. Two isolates were allocated to the lineage L3b, actxAB-negative buttcpA-positive clade previously associated with regional outbreaks. The remaining 29 isolates were placed in lineage L4, which is associated with environmental strains. Genes or mutations associated with reduced susceptibility to the first-line antibiotics fluoroquinolones and tetracyclines were identified in 11 and 3 isolates, respectively. One isolate was predicted to be multidrug resistant. V. choleraeinfections in Switzerland are rare and predominantly caused by lowly virulentctxAB-negative andtcpA-negative strains. AsV. choleraeis not endemic in Switzerland, cases are assumed to be acquired predominantly during travel. This assumption was supported by the phylogenetic diversity of the analysed isolates.

An unusual diarrheal outbreak in the community in Eastern Thailand caused by Norovirus GII.3[P25

BackgroundSentinel laboratory surveillance for diarrheal disease determined norovirus to be the most common cause of non-bacterial gastroenteritis in people during the COVID-19 pandemic in Thailand. An increase in patients presenting with diarrhea and vomiting in hospitals across Chanthaburi province between December 2021 and January 2022 led to the need for the identification of viral pathogens that may be responsible for the outbreak.MethodsFecal samples (rectal swabs or stool) from 93 patients, of which 65 patients were collected during the December 2021 to January 2022 outbreak, were collected and screened for viral infection by real-time RT-PCR. Positive samples for norovirus GII were then genotyped by targeted amplification and sequencing of partial polymerase and capsid genes. Full genome sequencing was performed from the predominant strain, GII.3[P25].ResultsNorovirus was the most common virus detected in human fecal samples in this study. 39 of 65 outbreak samples (60%) and 3 of 28 (10%) non-outbreak samples were positive for norovirus genogroup II. One was positive for rotavirus, and one indicated co-infection with rotavirus and norovirus genogroups I and II. Nucleotide sequences of VP1 and RdRp gene were successfully obtained from 28 of 39 positive norovirus GII and used for dual-typing; 25/28 (89.3%) were GII.3, and 24/28 (85.7) were GII.P25, respectively. Norovirus GII.3[P25] was the predominant strain responsible for this outbreak. The full genome sequence of norovirus GII.3[P25] from our study is the first reported in Thailand and has 98.62% and 98.57% similarity to norovirus found in China in 2021 and the USA in 2022, respectively. We further demonstrate the presence of multiple co-circulating norovirus genotypes, including GII.21[P21], GII.17[P17], GII.3[P12] and GII.4[P31] in our study.ConclusionsAn unusual diarrhea outbreak was found in December 2021 in eastern Thailand. Norovirus strain GII.3[P25] was the cause of the outbreak and was first detected in Thailand. The positive rate during GII.3[P25] outbreak was six times higher than sporadic cases (GII.4), and, atypically, adults were the primary infected population rather than children.

Outbreak of piglet diarrhea associated with a new reassortant porcine rotavirus B

Rotavirus B (RVB) is a causative agent leading to acute viral gastroenteritis diarrhea in both children and young animals, and has been commonly detected in piglets. In order to determine the causative agent of diarrheal outbreak occurring in December 2022 in piglets from a pig herd in Luoyang, Henan province of China, four common viral pathogens causing piglet diarrhea-three coronaviruses and rotavirus A (RVA) were first tested and found negative, therefore metagenomic sequencing was performed to explore other potential pathogens in the diarrheal samples. Unexpectedly, the most abundant viral reads mapped to RVB, and were de novo assembled to complete 11 viral gene segments. Sequence comparisons revealed that 5 gene segments encoding VP1, VP2, VP3, NSP3 and NSP4 of RVB strain designated as HNLY-2022 are most closely related to RVB strains derived from herbivores with low nucleotide similarities of 65.7–75.3%, and the remaining segments were relatively close to porcine RVB strains with the VP4 gene segment showing very low nucleotide identity (65.0%) with reference strains, indicating HNLY-2022 is a new reassortant RVB strain. Based on the previously proposed genotype classification criterion, the genotype constellation of RVB strain HNLY-2022 is G6-P[6]-I4-R6-C6-M6-A7-N5-T7-E5-H4 with more than half of the genotypes (P[6], R6, C6, M6, T7 and E5) newly reported. Therefore, the new reassortant RVB strain is the likely causative agent for the diarrheal outbreak of piglets occurred in China and more epidemiological studies should be conducted to monitor the spread of this newly identified porcine RVB strain.

An Epidemiological Investigation of Acute Diarrheal Disease Outbreak at Urban Area in Borsad Taluka of Anand District

Introduction: Acute Diarrheal Disease (ADD) is affecting millions of people around the world especially in second world nations now a days. Major pathogenic organisms that cause diarrhea, are transmitted through feco-oral route. We investigated an outbreak of Acute Diarrheal Disease at urban area of Borsad taluka, Anand District of Gujarat state with Objectives: 1. To confirm the existence of an outbreak, 2. To know the magnitude and distribution of the outbreak with reference to time, place and person, 3. To identify the source of infection, mode of transmission and implement control and preventive measures. Method: A Cross Sectional Epidemiological study was carried out to investigate the outbreak of acute diarrheal disease cases in urban area of Borsad taluka. We obtained required information from Chief District Health Office, Anand &amp;, Community Health Centre, borsad, conducted house to house survey and also inspected the sanitation and water supply of the affected area. Results: There were 72 cases of acute diarrheal disease. The overall Attack Rate was 0.43%. Majority of the affected population used non-chlorinated water for drinking. Conclusion: The underlying cause for the outbreak of acute diarrheal disease can be co-related by consumption of contaminated water and food. Keywords: Acute Diarrheal Disease, Borsad, Chlorination, Epidemic Investigation.

Molecular epidemiology and antimicrobial susceptibility of diarrheagenic Escherichia coli isolated from children under age five with and without diarrhea in Central Ethiopia.

Diarrhea is a serious health problem in children, with the highest mortality rate in sub-Saharan Africa. Diarrheagenic Escherichia coli (DEC) is among the major bacterial causes of diarrhea in children under age five. The present study aims to determine molecular epidemiology and antimicrobial resistance profiles of DEC and identify contributing factors for acquisition among children under age five in Central Ethiopia. A health facility-centered cross-sectional study was conducted in Addis Ababa and Debre Berhan, Ethiopia, from December 2020 to August 2021. A total of 476 specimens, 391 from diarrheic and 85 from non-diarrheic children under age five were collected. Bacterial isolation and identification, antimicrobial susceptibility, and pathotype determination using polymerase chain reaction (PCR) were done. Of the 476 specimens analyzed, 89.9% (428/476) were positive for E. coli, of which 183 were positive for one or more genes coding DEC pathotypes. The overall prevalence of the DEC pathotype was 38.2% (183/476). The predominant DEC pathotype was enteroaggregative E. coli (EAEC) (41.5%, 76/183), followed by enterotoxigenic E. coli (21.3%, 39/183), enteropathogenic E. coli (15.3%, 28/183), enteroinvasive E. coli (12.6%, 23/183), hybrid strains (7.1%, 13/183), Shiga toxin-producing E. coli (1.6%, 3/183), and diffusely-adherent E. coli (0.6%, 1/183). DEC was detected in 40.7% (159/391) of diarrheic and 28.2% (24/85) in non-diarrheic children (p = 0.020). The majority of the DEC pathotypes were resistant to ampicillin (95.1%, 174/183) and tetracycline (91.3%, 167/183). A higher rate of resistance to trimethoprim-sulfamethoxazole (58%, 44/76), ciprofloxacin (22%, 17/76), ceftazidime and cefotaxime (20%, 15/76) was seen among EAEC pathotypes. Multidrug resistance (MDR) was detected in 43.2% (79/183) of the pathotypes, whereas extended spectrum ß-lactamase and carbapenemase producers were 16.4% (30/183) and 2.2% (4/183), respectively. All six common DEC pathotypes that have the potential to cause severe diarrheal outbreaks were found in children in the study area; the dominant one being EAEC with a high rate of MDR.

Composition of mucus- and digesta-associated bacteria in growing pigs with and without diarrhea differed according to the presence of colonic inflammation

BackgroundIn the pig production, diarrhea can occur during different growth stages including the period 4–16 weeks post weaning, during which a diarrheal outbreak also termed as colitis-complex diarrhea (CCD) can occur and it is distinct from post-weaning diarrhea (1–2 weeks post weaning). We hypothesized that CCD in growing pigs is associated with changes in colonic microbiota composition and fermentation patterns, and the aim of the present observational study was to identify changes in digesta-associated bacteria (DAB) and mucus-associated bacteria (MAB) in the colon of growing pigs with and without diarrhea. A total number of 30 pigs (8, 11, and 12 weeks of age) were selected; 20 showed clinical signs of diarrhea and 10 appeared healthy. Based on histopathological examination of colonic tissues, 21 pigs were selected for further studies and classified as follows: without diarrhea, no colon inflammation (NoDiar; n = 5), with diarrhea, without colonic inflammation (DiarNoInfl; n = 4), and with diarrhea, with colonic inflammation (DiarInfl; n = 12). Composition (based on 16S rRNA gene amplicon sequencing) and fermentation pattern (short-chain fatty acids; SCFA profile) of the DAB and MAB communities were characterized.ResultsThe DAB showed higher alpha diversity compared to MAB in all pigs, and both DAB and MAB showed lowest alpha diversity in the DiarNoInfl group. Beta diversity was significantly different between DAB and MAB as well as between diarrheal groups in both DAB and MAB. Compared to NoDiar, DiarInfl showed increased abundance of various taxa, incl. certain pathogens, in both digesta and mucus, as well as decreased digesta butyrate concentration. However, DiarNoInfl showed reduced abundance of different genera (mainly Firmicutes) compared to NoDiar, but still lower butyrate concentration.ConclusionDiversity and composition of MAB and DAB changed in diarrheal groups depending on presence/absence of colonic inflammation. We also suggest that DiarNoInfl group was at the earlier stage of diarrhea compared with DiarInfl, with a link to dysbiosis of colonic bacterial composition as well as reduced butyrate concentration, which plays a pivotal role in gut health. This could have led to diarrhea with inflammation due to a dysbiosis, associated with an increase in e.g., Escherichia-Shigella (Proteobacteria), Helicobacter (Campylobacterota), and Bifidobacterium (Actinobacteriota), which may tolerate or utilize oxygen and cause epithelial hypoxia and inflammation. The increased consumption of oxygen in epithelial mucosal layer by infiltrated neutrophils may also have added up to this hypoxia. Overall, the results confirmed that changes in DAB and MAB were associated with CCD and reduced butyrate concentration in digesta. Moreover, DAB might suffice for future community-based studies of CCD.

A snap-shot of a diarrheal epidemic in Dhaka due to enterotoxigenic Escherichia coli and Vibrio cholerae O1 in 2022.

Enterotoxigenic Escherichia coli (ETEC) and Vibrio cholerae O1 are most common bacterial causes of diarrheal diseases in Bangladesh. This analysis projected distribution of ETEC and V. cholerae O1 among diarrheal patients of icddr,b, Dhaka hospital in two diarrheal peaks of 2022. Under the 2% systematic surveillance system, stool samples collected from diarrheal patients of icddr,b hospital were cultured and diagnostic testing was done for ETEC and V. cholerae O1. Comparison of positive cases was done between first peak (March-April) and second peak (October-November) in 2022. A total of 2,937 stool specimens were tested of which 12% were ETEC and 20% were V. cholerae O1. About 40% of the severe dehydration cases were infected with V. cholerae O1. Predominant ETEC enterotoxin type was 'LT/ST' (41%). The LT enterotoxin significantly increased from 13% to 28% in the second peak (p = 0.015). The predominant colonization factors (CFs) on ETEC were CS5 + CS6 (23%), followed by CS6 (15%). CF-positive isolates was significantly higher in the second peak (36%) than in the first peak (22%) (p = 0.043). Total 14% cases were co-infected with ETEC and V. cholerae O1. Significant differences in the distribution of enterotoxin types were observed (p = 0.029) among the co-infection cases. Changing patterns of enterotoxin and CFs observed in ETEC pathogens should be taken into consideration for ETEC vaccine development. Considering cholera and ETEC biannual trends in causing diarrheal epidemics and outbreaks, emphasizes the need for thoughts on combination vaccine strategies for preventing acute watery diarrhea due to the two major bacterial pathogens.

Acute Diarrheal Outbreak in 2022 Karachi, Pakistan: To Determine its Clinical Spectrum, Risk Factors and Complications

Acute Diarrheal Outbreak in 2022 Karachi, Pakistan: To Determine its Clinical Spectrum, Risk Factors and Complications

Novel strains of Campylobacter cause diarrheal outbreak in Rhesus macaques (Macaca mulatta) of Kathmandu Valley.

Campylobacter spp. is often underreported and underrated bacteria that present real health risks to both humans and animals, including non-human primates. It is a commensal microorganism of gastrointestinal tract known to cause gastroenteritis in humans. Commonly found in many wild animals including non-human primates (monkeys- Rhesus macaques) these pathogens are known to be a common cause of diarrhea in humans in many parts of developing and under developed countries. Rhesus macaques from the two holy sites in Kathmandu (Pashupati and Swoyambhu) were included in this cross-sectional study. Diarrheal samples of monkeys were analyzed to detect and characterize the pathogen using 16S rRNA-based PCR screening, followed by DNA sequencing and phylogenetic analysis. Out of a total 67 collected diarrheal samples, Campylobacter spp. were detected in the majority of the samples (n = 64; 96%). DNA sequences of the amplified PCR products were successfully obtained from 13 samples. Phylogenetic analysis identified Candidatus Campylobacter infans (n = 10, Kimura-2 parameter (K2P) pairwise distance values of 0.002287). Remaining three sequences might potentially belong to a novel Campylobacter species/sub-species- closely relating to known species of C. helviticus (K2P pairwise distance of 0.0267). Both Candidatus Campylobacter infans and C. helvitucus are known to infect humans and animals. Additionally, we also detected the bacteria in water and soil samples from the sites. Campylobacter spp. caused the 2018 diarrhea outbreak in Rhesus macaques in the Kathmandu valley. Campylobacter might be one of the important contributing pathogens in diarrheal outbreaks-both in humans and animals (monkeys) in Nepal. Due to close interactions of these animals with humans and other animals, One Health approach might be the most effective way to prevent and mitigate the threat posed by this pathogen.

Sequential outbreaks due to mixed ctxB alleles of Vibrio cholerae O1 in Mayurbhanj district of Odisha, India.

Cholera is a significant threat causing outbreaks/epidemics with high morbidity and mortality in coastal and tribal districts of Odisha. A sequential cholera outbreak reported from four places in Mayurbhanj district of Odisha during June to July 2009 was investigated. Rectal swabs from diarrhea patients were analyzed for the identification, antibiogram profiles and detection of ctxB genotypes by double mismatch amplification mutation (DMAMA) polymerase chain reaction (PCR) assays and sequenced. The different virulent and drug resistant genes were detected by multiplex PCR assays. The clonality analysis on selected strains was done by pulse field gel electrophoresis (PFGE). Bacteriological analysis of rectal swabs revealed the presence of V. cholerae O1 Ogawa biotype El Tor which were resistant to co-trimoxazole, chloramphenicol, streptomycin, ampicillin, nalidixic acid, erythromycin, furazolidone and polymyxin B. DMAMA-PCR assay revealed that the cholera outbreak in Mayurbhanj district was due to both ctxB1 and ctxB7 alleles of V. cholerae O1 El Tor strains. All the V. cholerae O1 strains were positive for all virulence genes. The multiplex PCR assay on V. cholerae O1 strains revealed the presence of antibiotic resistance genes like dfrA1 (100%), intSXT (100%), sulII (62.5%) and StrB (62.5%). PFGE results on V. cholerae O1 strains exhibited two different pulsotypes with 92% similarity. This outbreak was a transition phase where both ctxB genotypes were prevalent after which the ctxB7 genotype gradually became dominant in Odisha. Therefore, close monitoring and continuous surveillance on diarrheal disorders is essential to prevent the future diarrheal outbreaks in this region.

Past, current, and potential treatments for cryptosporidiosis in humans and farm animals: A comprehensive review.

The intracellular protozoan parasite of the genus Cryptosporidium is among the leading causes of waterborne diarrheal disease outbreaks throughout the world. The parasite is transmitted by ingestion of infective oocysts that are highly stable in the environment and resistant to almost all conventional disinfection methods and water treatments. Control of the parasite infection is exceedingly difficult due to the excretion of large numbers of oocysts in the feces of infected individuals that contaminate the environment and serve as a source of infection for susceptible hosts including humans and animals. Drug development against the parasite is challenging owing to its limited genetic tractability, absence of conventional drug targets, unique intracellular location within the host, and the paucity of robust cell culture platforms for continuous parasite propagation. Despite the high prevalence of the parasite, the only US Food and Drug Administration (FDA)-approved treatment of Cryptosporidium infections is nitazoxanide, which has shown moderate efficacy in immunocompetent patients. More importantly, no effective therapeutic drugs are available for treating severe, potentially life-threatening cryptosporidiosis in immunodeficient patients, young children, and neonatal livestock. Thus, safe, inexpensive, and efficacious drugs are urgently required to reduce the ever-increasing global cryptosporidiosis burden especially in low-resource countries. Several compounds have been tested for both in vitro and in vivo efficacy against the disease. However, to date, only a few experimental compounds have been subjected to clinical trials in natural hosts, and among those none have proven efficacious. This review provides an overview of the past and present anti-Cryptosporidium pharmacotherapy in humans and agricultural animals. Herein, we also highlight the progress made in the field over the last few years and discuss the different strategies employed for discovery and development of effective prospective treatments for cryptosporidiosis.

Genomic Characterization of Salmonella enterica serovar Weltevreden Associated with Human Diarrhea.

Salmonella Weltevreden is an emerging pathogen associated with human diarrhea, and knowledge of the genomics and epidemiology of this serovar is still limited. In this study, we performed whole-genome sequencing of 96 S. Weltevreden isolates recovered from diarrheal patients and 62 isolates from food animals in China between 2006 and 2017. Together, with an additional 199 genome sequences of S. Weltevreden published in NCBI, we performed an analysis on all 357 S. Weltevreden genome sequences. Our results demonstrated that the majority of S. Weltevreden from diarrheal patients from China (97.92%, 94/96) and the other regions in the world (94.97%, 189/199) identified in this study were sequence type (ST) 365. The remaining types were ST3771 (n = 3), ST22 (n = 1), ST155 (n = 1), and ST684 (n = 1). In addition, ST365 was also widely recovered from animals, food, and environmental samples in different regions of the world. Phylogenetic analysis and pulsed-field gel electrophoresis (PFGE) revealed that S. Weltevreden from diarrheal patients was closely related to those recovered from food and environmental specimens. We also showed that S. Weltevreden did not exhibit severe antimicrobial resistance profiles, suggesting administering antibiotics is still effective for controlling the agent. Interestingly, we found that S. Weltevreden strains carried a number of virulence factor genes, and a 100.03-kb IncFII(S) type plasmid was widely distributed in S. Weltevreden strains. Elimination of this plasmid decreased the bacterial capacity to infect both Caco-2 cells and C57BL/6 mice, suggesting the importance of this plasmid for bacterial virulence. Our results contribute to the understanding of the epidemiology and virulence of S. Weltevreden. IMPORTANCE Salmonella Weltevreden is a pathogen associated with human diarrheal diseases found across the globe. However, knowledge of the genomics and epidemiology of this pathogen is still limited. In this study, we found S. Weltevreden sequence type (ST) 365 is commonly recovered from diarrheal patients in China and many other regions of the world, and there is no major difference between the Chinese isolates and the global isolates at the phylogenetic level. We also demonstrated that ST365 was widely recovered from animal, food, and environmental samples collected in different, global regions. Importantly, we discovered an IncFII(S) type plasmid commonly carried by S. Weltevreden strains of human, animal, and food origins, and this plasmid is likely to contribute to the bacterial pathogenesis. These findings enhance our understanding of the emergence of S. Weltevreden involved in diarrheal outbreaks and the global spread of S. Weltevreden strains.

Cholera outbreak investigation report in Mille woreda, Afar region, Ethiopia, 2019

Introduction: Cholera has remained as one of the important public health problems in Asia and Africa causing substantial morbidity and mortality. Although the burden is greatest in low-income populations with poor access to safe water, and sanitation, cholera is also an important health problem globally. Cholera occurs both as a short outbreak and protracted epidemic/pandemic and when uncontrolled; is devastating to communities and to their prospects for development. To respond quickly and control the outbreak, investigation is crucial; identify risk factors that cause the outbreak, and suggest prevention and control measures. Objective: To identify risk factors and etiology of diarrheal disease outbreak and suggest prevention and control measures in Mille woreda, Afar region Ethiopia, May- June, 2018. Method: Descriptive followed by unmatched case-control study with 1:2 ratio were conducted from May-June 2018. A total of 68 patients and 136 controls were enrolled. A structured interviewer-administered questionnaire was used and medical records and line lists review. Simple random sampling was used to select controls and the first 68 cases. Data were analyzed by SPSS and presented using odd ratio, and tables. Environmental and patient samples were collected for culture and rapid diagnostic test. Result: The investigation identified 229 cholera patients, including 22 rapid diagnostic test confirmed patients and seven culture confirmed patients (attack rate: 8.31%, 229/27,562). Index patient were imported from epi-linked woreda. Diglena geraro kebele were the Epicenter of the outbreak. Epicure trend shows common source infection. Using bifurcation of Awash River for drinking, use untreated/ uncoiled water, poor hand washing practices, and close contact with cholera sick person were found to be associated with cholera. Conclusion: This outbreak was caused by vibrio cholera 01 secondary to drinking water from a bifurcation of Awash River and using untreated water. Contact with diseased person, and use untreated/ uncoiled water was associated with being patients. In order to reduce the risk of cholera, safe drinking water or water treatment chemicals needs to be provided to communities.

Facilitating hand hygiene in displacement camps during the COVID-19 pandemic: a qualitative assessment of a novel handwashing stand and hygiene promotion package

BackgroundHandwashing with soap is critical for the prevention of diarrhoeal diseases and outbreak related diseases, including interrupting the transmission of COVID-19. People living in large displacement settings are particularly vulnerable to such outbreaks, however, practicing handwashing is typically challenging in these contexts.MethodsWe conducted a qualitative assessment of the implementation of a combined intervention to facilitate handwashing behaviour in displacement camps and in surrounding communities in Bangladesh, Ethiopia and the Democratic Republic of Congo during the COVID-19 pandemic. The intervention comprised a ‘hardware’ infrastructural component (provision of the Oxfam Handwashing Station) and a ‘software’ hygiene promotion package (Mum’s Magic Hands). We used programmatic logbooks, interviews with implementation staff and focus group discussions with crisis-affected populations to assess the use, feasibility and acceptability of the intervention.ResultsBoth components of the intervention were viewed as novel and appealing by implementing staff and crisis-affected populations across the study sites. The acceptability of the handwashing station could be improved by redesigning the tap and legs, exploring local supply chain options, and by providing a greater number of facilities. The implementation of the hygiene promotion package varied substantially by country making it challenging to evaluate and compare. A greater focus on community engagement could address misconceptions, barriers related to the intuitiveness of the handwashing station design, and willingness to participate in the hygiene promotion component.ConclusionsThe combination of a ‘hardware’ and ‘software’ intervention in these settings appeared to facilitate both access and use of handwashing facilities. The acceptability of the combined intervention was partially because a great deal of effort had been put into their design. However, even when delivering well-designed interventions, there are many contextual aspects that need to be considered, as well as unintended consequences which can affect the acceptability of an intervention.