The etiology of severe acute gastroenteritis among adults visiting emergency departments in the United States

Effects of Rotavirus Vaccination Coverage among Infants on Hospital Admission for Gastroenteritis across All Age Groups, Japan, 2011-2019

We assessed the effect of rotavirus vaccination coverage on the number of inpatients with gastroenteritis of all ages in Japan. We identified patients admitted with all-cause gastroenteritis during 2011-2019 using data from the Diagnosis Procedure Combination system in Japan. We used generalized estimating equations with a Poisson distribution, using hospital codes as a cluster variable to estimate the impact of rotavirus vaccination coverage by prefecture on monthly numbers of inpatients with all-cause gastroenteritis. We analyzed 294,108 hospitalizations across 569 hospitals. Higher rotavirus vaccination coverage was associated with reduced gastroenteritis hospitalizations compared with the reference category of vaccination coverage <40% (e.g., for coverage >80%, adjusted incidence rate ratio was 0.87 [95% CI 0.83-0.90]). Our results show that achieving higher rotavirus vaccination coverage among infants could benefit the entire population by reducing overall hospitalizations for gastroenteritis for all age groups.

Prevalence, antibiotic susceptibility, and genomic analysis of Vibrio alginolyticus isolated from seafood and freshwater products in China

Introduction

This study characterized Vibrio alginolyticus isolated from seafood and freshwater products in China (2020).

Methods and Results

In total, 122 (95.31%) V. alginolyticus isolates were resistant to at least 1 antibiotic category, and 2 (1.56%) isolates were resistant to at least 3 antibiotic categories and belong to multi-drug resistance (MDR) isolates. A high prevalence rate was observed to be blaCARB (98.04%) encoding beta-lactam resistance, followed by tet (97.06%) encoding tetracycline resistance and fos (4.90%) encoding resistance to fosfomycin. Among the 57 V. alginolyticus isolates, the commonest virulence genes were type III secretion system translocated gene vopD, vopB, and vcrH (54.4%, 31/57), type III secretion system regulated gene tyeA (54.39%), followed by vscI and vscF (50.88%) encoded type III secretion system inner rod protein and needle protein, respectively. Multilocus sequence typing (MLST) showed considerable genetic diversity, with 34 distinct sequence types (STs) identified among 55 isolates. ST421 (n = 5), ST166 (n = 4), ST523 (n = 3), ST516 (n = 3), and ST507 (n = 3) were dominant STs among 55 V. alginolyticus isolates.

Discussion

These findings highlight the widespread occurrence of V. alginolyticus in both freshwater and seafood products, underscoring the critical need for vigilant monitoring of these bacteria. Such measures are essential for ensuring effective food safety management and safeguarding public health.

Presentation, management, and outcomes of norovirus in adult and pediatric solid organ and hematopoietic stem cell transplant recipients: A multicenter, retrospective study

BACKGROUND

Norovirus (NoV) can cause chronic relapsing and remitting diarrhea in immunocompromised patients.  Few multicenter studies have described the clinical course, outcomes, and complications of chronic NoV in transplant recipients.

METHODS

A multicenter retrospective study of adult and pediatric SOT and HSCT recipients diagnosed with NoV between November 1, 2017, and February 28, 2021. Data were obtained from electronic medical records (EMR) and entered into a central REDCap database. Descriptive statistics were calculated.

RESULTS

A total of 280 NoV+ patients were identified across eight sites. The majority were adults (74.1%) and SOT recipients (91.4%). Initial diagnosis of NoV occurred a median of 36 months post-Tx (IQR [15.0, 90.0]). Most NoV cases had >3 diarrheal episodes daily (66.0%), nausea and vomiting (60.1%). Duration of diarrhea varied greatly (median = 10 days, mean = 85.9 days, range (1, 2100)). 71.3% were hospitalized. Adjustment of immunosuppression, including reduction and discontinuation of mToR inhibitor, CNI, and/or MMF, was the most common management intervention for NoV. Other therapies resulted only in temporary improvement. Four patients died within 30 days and three others died by 180 days postdiagnosis. Clinically significant renal dysfunction was observed in 12.5% by 30 days and 21.4% by 180 days post-NoV diagnosis.

CONCLUSION

In HSCT and SOT patients, NoV frequently resulted in severe symptoms, prolonged diarrhea (30% persistent with diarrhea for >30 days), and clinically significant renal dysfunction (up to 21% of patients). Utilized therapies did not reliably result in the resolution of infection demonstrating the need for more effective treatment.

Nausea, Vomiting, and Nonbloody Diarrhea in the Emergency Department

Nausea, vomiting and diarrhea are frequent co-occurring symptoms that can mask or mimic commonly occurring conditions, or rarely, more serious concerns. The Ending the HIV Epidemic's focus on increased widespread use of PrEP, a biomedical HIV prevention strategy, highlights the importance of discussing common clinical management scenarios. The use of oral PrEP formulations has demonstrated a "startup syndrome" which involves GI upset. This case challenge of a 32year old client admitted to the ED with GI symptoms highlights key PrEP considerations including a sexual health history. Clinicians should understand common complaints associated with oral PrEP start to improve differential diagnosis and appropriate intervention.

Epidemiology and aetiology of moderate to severe diarrhoea in hospitalised patients ≥5 years old living with HIV in South Africa, 2018-2021: A case-control analysis

Diarrhoea is a recognised complication of HIV-infection, yet there are limited local aetiological data in this high-risk group. These data are important for informing public health interventions and updating diagnostic and treatment guidelines. This study aimed to determine the pathogenic causes of diarrhoeal admissions in people living with HIV (PLHIV) compared to hospital controls between July 2018 and November 2021. Admitted diarrhoeal cases (n = 243) and non-diarrhoeal hospital controls (n = 101) ≥5 years of age were enrolled at Kalafong, Mapulaneng and Matikwana hospitals. Stool specimens/rectal swabs were collected and pathogen screening was performed on multiple platforms. Differences in pathogen detections between cases and controls, stratified by HIV status, were investigated. The majority (n = 164, 67.5%) of enrolled diarrhoeal cases with known HIV status were HIV-infected. Pathogens could be detected in 66.3% (n = 228) of specimens, with significantly higher detection in cases compared to controls (72.8% versus 50.5%, p<0.001). Amongst PLHIV, prevalence of Cystoisospora spp. was significantly higher in cases than controls (17.7% versus 0.0%, p = 0.028), while Schistosoma was detected more often in controls than cases (17.4% versus 2.4%, p = 0.009). Amongst the HIV-uninfected participants, prevalence of Shigella spp., Salmonella spp. and Helicobacter pylori was significantly higher in cases compared to controls (36.7% versus 12.0%, p = 0.002; 11.4% versus 0.0%, p = 0.012; 10.1% versus 0.0%, p = 0.023). Diarrhoeal aetiology differed by HIV status, with Shigella spp. (36.7%) and Salmonella spp. (11.4%) having the highest prevalence amongst HIV-uninfected cases and Shigella spp. (18.3%), Cystoisospora (17.7%), and Cryptosporidium spp. (15.9%) having the highest prevalence in cases amongst PLHIV. These differences should be considered for the development of diagnostic and treatment guidelines.

A Unique Case of Pseudomonas aeruginosa-Associated Diarrhea in a Long-Term Hospitalized Adult Patient

A 53-year-old Caucasian man with a history of alcohol use disorder, hypertension, and hypothyroidism presented with a myxedema coma requiring intubation. He had a complicated hospital course with ventilator-associated pneumonia with MRSA, sepsis with candida, and abdominal compartment syndrome requiring decompressive laparotomy. The patient slowly recovered during 43 days of hospitalization. During the intensive care unit (ICU) stay, a flexi-seal rectal tube was placed due to fecal incontinence. After being moved to a regular medicine unit, he started having loose watery stools with leukocytosis and neutrophilia. Clostridium difficile (C. diff.) colitis was suspected, and he was placed on oral vancomycin empirically. His stool test for C. diff. came back negative, and his rectal tube was subsequently removed. Imaging did not show any abscess, perforated viscus, or fistula formations. His stool culture grew a heavy colony of Pseudomonas aeruginosa (P. aeruginosa). Vancomycin was stopped, and he was started on oral ciprofloxacin 750 mg twice a day with complete resolution of his diarrhea and leukocytosis.

Relationship between Diagnostic Method and Pathogen Detection, Healthcare Resource Use, and Cost in U.S. Adult Outpatients Treated for Acute Infectious Gastroenteritis

A retrospective observational study was performed to assess the relationship between diagnostic method (traditional work-up [TW], multiplex PCR panel with < 12 target pathogens [PCR < 12], or multiplex PCR panel with ≥ 12 target pathogens [PCR12]), and diagnostic yield, health care resource use (HRU), and cost in adult outpatients visiting U.S. hospitals for acute infectious gastroenteritis (AGE). Using data from PINC AI Healthcare Database during January 1, 2016-June 30, 2021, we analyzed adult patients with an AGE diagnosis and stool testing performed during an outpatient visit. Detection rates for different pathogens were analyzed for those with microbiology data available. Among 36,787 patients, TW was most often performed (57.0%). PCR12 testing was more frequent in patients from large, urban, and teaching hospitals, compared to TW (all P < 0.01). PCR12 was associated with a higher mean index visit cost (by $97) but lower mean 30-day AGE-related follow-up cost (by $117) than TW. Patients with PCR12 had a lower 30-day AGE-related hospitalization risk than TW (1.7% versus 2.7% P < 0.01). Among the 8,451 patients with microbiology data, PCR12 was associated with fewer stool tests per patient (mean 1.61 versus 1.26), faster turnaround time (mean 6.3 versus 25.7 h) and lower likelihood of receiving in-hospital antibiotics (39.4% versus 47.1%, all P < 0.01) than TW. A higher percentage of patients with PCR12 had a target pathogen detected (73.1%) compared to PCR < 12 (63.6%) or TW (45.4%, P < 0.01). Thus, we found that large multiplex PCR panels were associated with lower 30-day AGE-related follow-up cost and risk of AGE-related hospitalization, and increased diagnostic yield compared to TW.

Epidemiology and Economic Burden of Acute Infectious Gastroenteritis Among Adults Treated in Outpatient Settings in US Health Systems

INTRODUCTION

Acute infectious gastroenteritis (AGE) is a common reason for outpatient visits and hospitalizations in the United States. This study aimed to understand the demographic and clinical characteristics, common pathogens detected, health care resource utilization (HRU), and cost among adult outpatients with AGE visiting US health systems.

METHODS

A retrospective cohort study was conducted using one of the largest hospital discharge databases (PINC AI Healthcare Database) in the United States. Adult patients (aged ≥18 years) with a principal diagnosis of AGE during an outpatient visit between January 1, 2016, and June 30, 2021, were included. Pathogen detection analysis was performed in those with microbiology data available.

RESULTS

Among 248,896 patients, the mean age was 44.3 years (range 18-89+ years), 62.9% were female, and 68.5% were White. More than half (62.0%) of the patients did not have any preexisting comorbidity, and only 18.3% underwent stool workup at the hospital. Most patients (84.7%) were seen in the emergency department, and most (96.4%) were discharged home. Within 30 days of discharge, 1.0% were hospitalized, and 2.8% had another outpatient visit due to AGE. The mean cost of the index visit plus 30-day AGE-related follow-up was $1,338 per patient, amounting to $333,060,182 for the total study population. Among patients with microbiology data available (n = 12,469), common pathogens detected were Clostridioides difficile (32.2%), norovirus (6.3%), and Campylobacter spp. (4.0%).

DISCUSSION

AGE is a common and costly disease affecting adults of all ages and more females than males, including individuals with or without baseline conditions in a hospital-based outpatient setting. C. difficile was the most common pathogen detected.

Antibiotic prescribing for acute gastroenteritis during ambulatory care visits-United States, 2006-2015

OBJECTIVE

To describe national antibiotic prescribing for acute gastroenteritis (AGE).

SETTING

Ambulatory care.

METHODS

We included visits with diagnoses for bacterial and viral gastrointestinal infections from the National Ambulatory Medical Care Survey and National Hospital Ambulatory Medical Care Survey (NAMCS/NHAMCS; 2006-2015) and the IBM Watson 2014 MarketScan Commercial Claims and Encounters Database. For NAMCS/NHAMCS, we calculated annual percentage estimates and 99% confidence intervals (CIs) of visits with antibiotics prescribed; sample sizes were too small to calculate estimates by pathogen. For MarketScan, we used Poisson regression to calculate the percentage of visits with antibiotics prescribed and 95% CIs, including by pathogen.

RESULTS

We included 10,210 NAMCS/NHAMCS AGE visits; an estimated 13.3% (99% CI, 11.2%-15.4%) resulted in antibiotic prescriptions, most frequently fluoroquinolones (28.7%; 99% CI, 21.1%-36.3%), nitroimidazoles (20.2%; 99% CI, 14.0%-26.4%), and penicillins (18.9%; 99% CI, 11.6%-26.2%). In NAMCS/NHAMCS, antibiotic prescribing was least frequent in emergency departments (10.8%; 99% CI, 9.5%-12.1%). Among 1,868,465 MarketScan AGE visits, antibiotics were prescribed for 13.8% (95% CI, 13.7%-13.8%), most commonly for Yersinia (46.7%; 95% CI, 21.4%-71.9%), Campylobacter (44.8%; 95% CI, 41.5%-48.1%), Shigella (39.7%; 95% CI, 35.9%-43.6%), typhoid or paratyphoid fever (32.7%; (95% CI, 27.2%-38.3%), and nontyphoidal Salmonella (31.7%; 95% CI, 29.5%-33.9%). Antibiotics were prescribed for 12.3% (95% CI, 11.7%-13.0%) of visits for viral gastroenteritis.

CONCLUSIONS

Overall, ∼13% of AGE visits resulted in antibiotic prescriptions. Antibiotics were unnecessarily prescribed for viral gastroenteritis and some bacterial infections for which antibiotics are not recommended. Antibiotic stewardship assessments and interventions for AGE are needed in ambulatory settings.

Common Etiological Agents in Adult Patients with Gastroenteritis from Central Iran

Aims: This study represents the first analysis from Iran for both the frequency of the most common causes of infectious diarrhoea and their antibiotic resistance patterns in adult patients. Methods: Adult stool specimens (n = 211) were analyzed. Stool specimens were analyzed using standard microbiological, polymerase chain reaction, and reverse transcription polymerase chain reaction tests to identify bacterial, parasitic, and viral enteropathogens. Antibiotic resistance profiles were determined. Results: Enteropathogens were identified in 46.4% (98/211) of the surveyed samples. This included 33.1% (70/211) bacterial infections, including 9.9% (21/211) diarrheagenic Escherichia coli (DEC) and 8.5% (18/211) Shigella spp. We detected 7.1% (15/211) parasitic infections (mostly Giardia lamblia) and 6.1% (13/211) viral infections (mostly adenovirus). The DEC and Shigella spp. isolates included many multi-drug resistant (MDR) isolates (95.2% and 77.7%, respectively), and extended spectrum-β-lactamase (ESBL) genes were often present (57.1% and 61.1%, respectively). The most commonly identified ESBL genes in the DEC and Shigella spp. isolates were bla_TEM (100% in both species), bla_CTX-M15 (91.6% and 100%, respectively), AmpC bla_CIT (80% and 100%, respectively), and bla_DHA (80% and 100%, respectively). Conclusions: Bacterial infection was the primary cause of infectious diarrhea, affecting one-third of the adults. The frequency of DEC and Shigella spp. was higher than for other enteropathogens. The high prevalence of MDR, the elevated incidence of ESBL genes among Shigella spp. and DEC isolates, and the presence of quinolone resistance in the Salmonella spp. isolates represent a significant challenge for gastroenteritis diagnosis and treatment in this region.

Management of acute diarrhea in the emergency department of a tertiary care university medical center

Objectives

To examine the management of acute diarrhea in the emergency department (ED) of a large university medical center.

Methods

Retrospective cross-sectional study over a 10-month period of adult patients (age ≥18 years) presenting to the ED with acute diarrhea.

Results

Data for 780 patients were reviewed; 101 met the exclusion criteria. Of the 679 patients with acute community-acquired diarrhea, 582 (85.7%) were discharged home and constituted the study cohort of mostly healthy adults (mean age: 32.5 ± 14.5 years). The rate of antibiotic prescription at discharge was 26%. Inappropriate use of antibiotics occurred in 28% of the patients. The presence of fever (odds ratio (OR) = 3.52), leukocytosis (OR = 1.72), and older age (OR = 1.16) were predictors of antibiotic prescription. Patients with dehydration, comorbidities, or bloody diarrhea were more likely to receive antibiotics. Microbiological studies and cross-sectional imaging were ordered in 12.4% and 11.7% of the patients, respectively, but provided very low yield (<10% for both) resulting in significantly higher visit charges. Inappropriately prescribed antibiotics at discharge resulted in higher charges in the ED compared with no antibiotic prescription.

Conclusion

Acute diarrhea management in our ED is suboptimal and does not adhere to practice guidelines, resulting in unnecessary antibiotic prescriptions, investigations, and cost.

Risk Factors for Acute Gastroenteritis Among Patients Hospitalized in 5 Veterans Affairs Medical Centers, 2016-2019

BACKGROUND

In the United States, ∼179 million acute gastroenteritis (AGE) episodes occur annually. We aimed to identify risk factors for all-cause AGE, norovirus-associated vs non-norovirus AGE, and severe vs mild/moderate AGE among hospitalized adults.

METHODS

We enrolled 1029 AGE cases and 624 non-AGE controls from December 1, 2016, to November 30, 2019, at 5 Veterans Affairs Medical Centers. Patient interviews and medical chart abstractions were conducted, and participant stool samples were tested using the BioFire Gastrointestinal Panel. Severe AGE was defined as a modified Vesikari score of ≥11. Multivariate logistic regression was performed to assess associations between potential risk factors and outcomes; univariate analysis was conducted for norovirus-associated AGE due to limited sample size.

RESULTS

Among 1029 AGE cases, 551 (54%) had severe AGE and 44 (4%) were norovirus positive. Risk factors for all-cause AGE included immunosuppressive therapy (adjusted odds ratio [aOR], 5.6; 95% CI, 2.7-11.7), HIV infection (aOR, 3.9; 95% CI, 1.8-8.5), severe renal disease (aOR, 3.1; 95% CI, 1.8-5.2), and household contact with a person with AGE (aOR, 2.9; 95% CI, 1.3-6.7). Household (OR, 4.4; 95% CI, 1.6-12.0) and non-household contact (OR, 5.0; 95% CI, 2.2-11.5) with AGE was associated with norovirus-associated AGE. Norovirus positivity (aOR, 3.4; 95% CI, 1.3-8.8) was significantly associated with severe AGE.

CONCLUSIONS

Patients with immunosuppressive therapy, HIV, and severe renal disease should be monitored for AGE and may benefit from targeted public health messaging regarding AGE prevention. These results may also direct future public health interventions, such as norovirus vaccines, to specific high-risk populations.

Diagnoses of Exclusion in the Workup of Abdominal Complaints

Abdominal pain is a common complaint in the emergency department, comprising 8.8% of all visits. Despite advances in medicine and imaging, 20% to 30% of patients still leave the department without a definitive diagnosis, whichhis can be both distressing for patients and unsatisfying for providers. Diagnoses of exclusion can be perilous, and their application should be carefully considered in order to not overlook more emergent complaints. However, a working knowledge of diagnoses of exclusion can guide therapeutics and specialty referrals that can ultimately provide answers and relief to a patient population often at odds with available information and expectations.

Aetiology and risk factors of bacterial gastroenteritis among febrile outpatients at the Dschang District Hospital, West Region of Cameroon: a cross-sectional study

OBJECTIVES

To investigate the bacterial aetiologies and associated risk factors of gastroenteritis among typhoid suspected cases.

DESIGN

Cross-sectional study.

SETTING

This study was conducted at Dschang District Hospital of the Menoua Division, West Region of Cameroon, between April-November 2019 and June 2020.

PARTICIPANTS

Participants aged ≥2 years (mean 34±18.77 years) and of both sex suspected of having typhoid fever were included, while non-suspected typhoid cases were excluded. Self-reported sociodemographic and health information at recruitment was obtained from 556 participants.

METHODS

Collected stool samples were examined macroscopically and microscopically and subjected to culture. After culture, Gram staining was performed, followed by biochemical testing and characterisation using the Analytical Profile Index (API-20E) test kit.

INTERVENTIONS'

No intervention was done during the period of study.

OUTCOME MEASURES

We identified bacterial causing gastroenteritis, and associated risk factors calculated using binary regression, adjusting for sociodemographic and health variables.

RESULTS

Of 556 patients, 74.28% tested positive for gastroenteritis. Among pathogens responsible for gastroenteritis, Escherichia coli was found to be the main cause (21.1%), followed by Salmonella typhi (10.4%), Citrobacter diversus (8.2%), and Proteus mirabilis (8.2%), Proteus vulgaris (7.3%), whereas Citrobacter spp and Yersinia enterocolitica were less represented among pathogens causing the disease among patients. A significant difference (p=0.002) was observed between abdominal pain and all the micro-organisms isolated from the patients. Patients having primary level of education were significantly associated (p=0.017; 3.163 (95% CI 1.228 to 8.147)) with the prevalence of gastroenteritis. Consumption of beverages (Wald statistic: 4.823; OR: 2.471; 95% CI (1.102 to 5.539); p=0.028), use of modern toilet (Wald statistic: 4.471; OR: 1.723; 95% CI (1.041 to 2.852); p=0.034) were strongly associated with gastroenteritis and rearing of bird (Wald statistic: 4.880; OR: 0.560; 95% CI (0.335 to 0.937); p=0.027), was found to be protective.

CONCLUSION

Acute bacterial gastroenteritis is a significant cause of morbidity in Dschang, with the prevalence of 74.28%. Many pathogens accounted for gastroenteritis, and E. coli (21.1%) could be a major cause, followed by S. typhi (10.4%), C. diversus (8.2%), P. mirabilis (8.2%), P. vulgaris (7.3%), whereas Citrobacter spp and Y. enterocolitica were less represented. Gastroenteritis was highly associated with primary level of education, consumption of beverages, use of modern toilet while rearing of birds was unexpectedly found to be protective against Gastroenteritis. Further characterisation is planned.

Prevalence of rotavirus among older children and adults with diarrhea: A systematic review and meta-analysis

BACKGROUND

Older children and adults are susceptible to rotavirus, but the extent to which rotavirus affects this population is not fully understood, hindering accuracy of global rotavirus estimations.

OBJECTIVE

To determine what proportion of diarrhea cases are due to rotavirus among persons ≥ 5 years old and to estimate this proportion by age strata.

METHODS

We conducted a systematic review and meta-analysis using the PRISMA guidelines. We included studies that reported on conditional rotavirus prevalence (i.e., percent of diarrhea due to rotavirus) in persons ≥ 5 years old who were symptomatic with diarrhea/gastroenteritis and had laboratory confirmation for rotavirus infection. Studies on nosocomial infections and outbreak investigations were excluded. We collected age group-specific conditional rotavirus prevalence and other variables, such as study geography, study setting, and study type. We calculated pooled conditional rotavirus prevalence, corresponding 95% confidence intervals (95% CI), heterogeneity (I²) estimates, and prediction intervals (PI).

RESULTS

Sixty-six studies from 32 countries met the inclusion criteria. Conditional rotavirus prevalence ranged from 0% to 30% across the studies. The total pooled prevalence of rotavirus among persons ≥ 5 years old with diarrhea was 7.6% (95% CI: 6.2-9.2%, I² = 99.6%, PI: 0-24%). The pooled prevalence of rotavirus among older children and adolescents was 8.7% (95% CI: 6.2-11.7%, I² = 96%, PI:0-27%), among younger adults was 5.4% (95% CI: 1.4-11.8%, I² = 96%, PI:0-31%), and among older adults was 4.7% (95% CI: 2.8-7.0%, I² = 96%, PI:0-16%). Pooled conditional rotavirus prevalences did not differ by other variables.

CONCLUSION

In this systematic review and meta-analysis of rotavirus among persons ≥ 5 years old with diarrhea, we found relatively low pooled conditional rotavirus prevalence compared to what is typically reported for children < 5 years; however, results should be interpreted with caution as the wide prediction intervals suggest large heterogeneity.

Gastroenteritis in Men Who Have Sex With Men in Seattle, Washington, 2017-2018

BACKGROUND

Men who have sex with men (MSM) are at risk for sexual transmission of enteric pathogens. The microbiology of gastroenteritis in MSM has not been examined since the advent of antiretroviral therapy and molecular diagnostics. Our objective was to assess the causes of gastroenteritis among MSM living with and without human immunodeficiency virus (HIV) coinfection in Seattle, Washington.

METHODS

We conducted a retrospective cohort study of 235 MSM who underwent multiplex stool polymerase chain reaction (PCR) testing between 1 January 2017 and 1 June 2018. We abstracted clinical and laboratory data from electronic medical records. Parallel or reflexive culture and susceptibility testing were performed when PCR detected cultivable pathogens.

RESULTS

Among 235 MSM tested (268 episodes), 131 had 151 episodes with positive test results. 148 (63.0%) individuals were living with HIV. Among positive tests, 88.7% detected a bacterial pathogen, 26% a virus, and 40% a parasite. Diarrheagenic Escherichia coli (enteroaggretative, enteropathogenic), Shigella, and Campylobacter were the most commonly detected bacteria (33.1%, 30.5%, and 17.2% of positive samples, respectively). Forty-three percent of positive specimens had ≥2 pathogens. Etiologies and clinical presentations were similar between men living with and without HIV. Cultured Shigella and Campylobacter isolates were frequently resistant to multiple antibiotics.

CONCLUSIONS

MSM present with gastroenteritis from varied pathogens, including some not detected by conventional stool culture. High levels of antibiotic resistance are consistent with frequent antibiotic exposure in this population and the transmission of multiresistant strains. New approaches are needed to detect, treat, and prevent enteric infections in MSM.

Indirect impact of rotavirus vaccination on viral causes of acute gastroenteritis in the elderly

BACKGROUND

Rotavirus is considered a childhood infection causing acute gastroenteritis however, it also causes disease in adults which may be underestimated due to less frequent testing in this age-group.

OBJECTIVES

To determine if paediatric rotavirus vaccination, introduced into Ireland in December 2016, affected the viral aetiology in those aged ≥65 yrs presenting with gastroenteritis in the pre- and post-vaccination years. Additionally, rotavirus genotypes in this age-group will be described.

METHODS

Faecal samples from 2015 to 2019 for the investigation of gastroenteritis were tested by real-time (RT-) PCR for norovirus, adenovirus, rotavirus, Rotarix, astrovirus and sapovirus. Rotaviruses were genotyped by multiplex real-time RT-PCR or hemi-nested RT-PCR and a proportion confirmed by sequencing.

RESULTS

22,593 samples from adults aged ≥65 yrs were tested and 2566 (11 %) had ≥1 virus detected. Of 2566 positive samples, norovirus was detected in 82 %, rotavirus 9 %, sapovirus 6 %, astrovirus 3 % and adenovirus 1 %. Rotavirus and norovirus infections decreased between pre and post-vaccine year groups p < 0.001, whereas sapovirus, astrovirus and adenovirus remained unchanged. Between 2015-16 and 2018-19, G2P[4] increased and G4P[8] decreased, p < 0.001. In 2015-2019 there were 37 rotavirus outbreaks. Five geriatric outbreaks were genotyped and caused by G4P[8] (n = 1), G1P[8] (n = 1), G2P[4] (n = 2) and G12P[8] (n = 1).

CONCLUSION

Rotavirus causes acute gastroenteritis in older people. Paediatric vaccination may have contributed to a decline in infections in the elderly; nevertheless, rotavirus continued to circulate in older people following vaccine introduction. Genotype distribution changed between the pre- and post-vaccine era however genotypes in outbreak and endemic settings were comparable.

Accuracy and comparison of two rapid multiplex PCR tests for gastroenteritis pathogens: a systematic review and meta-analysis

Objectives

The primary aim is to provide a summary of evidence for the diagnostic accuracies of multiplex PCR gastrointestinal (GI) panels—BioFire FilmArray and Luminex xTAG on the detection of gastroenteritis pathogens. The secondary aim is to compare the performance of these GI panels head to head.

Methods

A comprehensive search up to 1 December 2019 was conducted on PubMed, Embase, Ovid Medline and Web of Science for studies that used FilmArray or Luminex xTAG Gastrointestinal Pathogen Panel (GPP) for diagnosis of acute gastroenteritis. A summary of diagnostic accuracies for the 16 pathogens were calculated by comparing the GI panels to the current gold standards (conventional standard microbiology techniques such as culture or PCR for bacteria, PCR or enzyme immunoassay (EIA) for viruses, microscopy or EIA for parasite). Hierarchical summary receiver operating characteristic (HSROC) curve analysis, pretest and post-test probabilities were used for estimating the pathogen detection performance.

Results

A total of 11 studies with 7085 stool samples were eligible for analysis. Multiplex PCRs demonstrated high diagnostic accuracy, with specificity ≧0.98 and area under the ROC curve (AUROC) ≧0.97 for all the pathogens except for Yersinia enterocolitica (AUROC 0.91). The FilmArray panel demonstrated a higher sensitivity than xTAG GPP for most of the pathogens with the exception of Rotavirus A (xTAG GPP and FilmArray were both 0.93).

Conclusions

This is the first meta-analysis that is a head-to-head comparison examining the performance of the novel multiplex PCR-based tests Luminex xTAG GPP and FilmArray GI panel in detecting each pathogen. Point estimates calculated from eligible studies showed that both GI panels are highly accurate and may provide important diagnostic information for early identification of gastroenteritis. In addition, although FilmArray has higher sensitivity and post-test probability than xTAG GPP for most of the pathogens, how this will translate to a clinical setting remains unclear.

Norovirus and Other Viral Causes of Medically Attended Acute Gastroenteritis Across the Age Spectrum: Results from the Medically Attended Acute Gastroenteritis Study in the United States

BACKGROUND

Acute gastroenteritis (AGE) causes a substantial burden in the United States, but its etiology frequently remains undetermined. Active surveillance within an integrated healthcare delivery system was used to estimate the prevalence and incidence of medically attended norovirus, rotavirus, sapovirus, and astrovirus.

METHODS

Active surveillance was conducted among all enrolled members of Kaiser Permanente Northwest during July 2014-June 2016. An age-stratified, representative sample of AGE-associated medical encounters were recruited to provide a stool specimen to be tested for norovirus, rotavirus, sapovirus, and astrovirus. Medically attended AGE (MAAGE) encounters for a patient occurring within 30 days were grouped into 1 episode, and all-cause MAAGE incidence was calculated. Pathogen- and healthcare setting-specific incidence estimates were calculated using age-stratified bootstrapping.

RESULTS

The overall incidence of MAAGE was 40.6 episodes per 1000 person-years (PY), with most episodes requiring no more than outpatient care. Norovirus was the most frequently detected pathogen, with an incidence of 5.5 medically attended episodes per 1000 PY. Incidence of norovirus MAAGE was highest among children aged < 5 years (20.4 episodes per 1000 PY), followed by adults aged ≥ 65 years (4.5 episodes per 1000 PY). Other study pathogens showed similar patterns by age, but lower overall incidence (sapovirus: 2.4 per 1000 PY; astrovirus: 1.3 per 1000 PY; rotavirus: 0.5 per 1000 PY).

CONCLUSIONS

Viral enteropathogens, particularly norovirus, are important contributors to MAAGE, especially among children < 5 years of age. The present findings underline the importance of judicious antibiotics use for pediatric AGE and suggest that an effective norovirus vaccine could substantially reduce MAAGE.

Recent developments in antimicrobial therapy for gastrointestinal infections

PURPOSE OF REVIEW

This focused, narrative review summarizes human clinical trial data for direct-acting antimicrobials in development for the treatment of gastrointestinal infections that were published in the past 18 months (1 January 2019 to 30 June 2020).

RECENT FINDINGS

Antimicrobial agents for Clostridioides difficile infection (n = 6), cryptosporidiosis (n = 1), cytomegalovirus infection (n = 3) and Helicobacter pylori infection (n = 1) have completed and/or are undergoing human clinical trials.

SUMMARY

Although this review highlights significant advances in four disease states, many common gastrointestinal pathogens have no antimicrobials in human clinical trials, emphasizing the need for continued prioritization in this field of study.

Evaluation of viral co-infections among patients with community-associated Clostridioides difficile infection

We assessed viral co-infections in 155 patients with community-associated Clostridioides difficile infection in five U.S. sites during December 2012–February 2013. Eighteen patients (12%) tested positive for norovirus (n = 10), adenovirus (n = 4), rotavirus (n = 3), or sapovirus (n = 1). Co-infected patients were more likely than non-co-infected patients to have nausea or vomiting (56% vs 31%; p = 0.04), suggesting that viral co-pathogens contributed to symptoms in some patients. There were no significant differences in prior healthcare or medication exposures or in CDI complications.

Use of BioFire FilmArray gastrointestinal PCR panel associated with reductions in antibiotic use, time to optimal antibiotics, and length of stay

BACKGROUND

Rapid and accurate diagnostic tools are needed for appropriate management of infectious diarrhea.

METHODS

We evaluated the impact of the introduction of rapid multiplex PCR testing using the FilmArray gastrointestinal (GI) panel (BioFire Diagnostics, LLC, Salt Lake City, UT) at our institution, and compared the results to those of standard stool cultures.

RESULTS

The most common pathogens detected by the FilmArray GI panel were Clostridium difficile (55.0%), Campylobacter species (20.9%), Salmonella species (12.4%), and Shigella/EIEC species (12.4%). Rates of reproducibility in stool culture for these pathogens ranged from 56.3 to 77.8%. Co-detection of two or more organisms was common (24.2%), most commonly involving EPEC, EAEC, ETEC, and STEC. The time from arrival in the Emergency Department to discharge or admission to the hospital was unchanged after the introduction of FilmArray GI panel, but length of hospital stay was shorter (3 vs. 7.5 days, p = 0.0002) for the FilmArray group. The time to empiric antibiotics did not differ significantly, but optimal antibiotics were started earlier after introduction of the FilmArray GI panel (hospital day 1 vs. 2, p < 0.0001). More patients were discharged without antibiotics after introduction of the FilmArray GI panel (14.0% vs. 4.5%; p < 0.001).

CONCLUSION

Our results demonstrate that the FilmArray GI panel is an important tool for improving both patient care and antibiotic stewardship, despite the tendency for positive results with multiple pathogens.

Stool cultures show a lack of impact in the management of acute gastroenteritis for hospitalized patients in the Bronx, New York

Background

Acute gastroenteritis (AGE) is diagnosed with a presentation of > 1 episode of vomiting and > 3 episodes of diarrhea in a 24-h period. Treatment is supportive, however, in severe cases antibacterial treatment may be indicated. Stool cultures can detect the responsible pathogenic bacteria and can guide antibiotic treatment, however, the indication for and efficacy of stool cultures is debatable. This study aimed to address the clinical utility of stool cultures in patients diagnosed with AGE.

Methods

A retrospective, multicenter study was performed in patients admitted for AGE from 2012 to 2014. Patient charts were obtained through hospital software using ICD-9 codes for AGE. Inclusion criteria was a documented diagnosis of AGE, age of 18 years or older, symptoms of both upper GI symptoms of abdominal pain and/or nausea and lower GI symptoms of diarrhea. Patients were classified into two main groups, those in whom (1) stool culture was obtained and (2) those in whom stool culture was not performed. Clinical features and outcomes were compared between groups. The diagnostic yield of stool cultures was assessed. All analysis were conducted using the Statistical Package for Social Science (SPSS).

Results

Of 2479 patient charts reviewed, 342 met the above criteria for AGE. 119 patients (34.8%) had stool cultures collected and 223 (65.2%) did not. Demographics, clinical features and serologic lab values are shown in Table 1. Of the 119 stool cultures performed, only 4% (n = 5) yielded growth of pathogenic bacteria (2 Pseudomonas spp, 2 Campylobacter spp, 1 Salmonella spp). The group who underwent stool culture had a higher percentage of patients with fevers (26% vs 13%,p < 0.003) and longer hospital length of stay (3.15 vs 2.28 days, p < 0.001) compared to the group that did not undergo stool cultures.

Conclusion

Stool cultures are commonly ordered when AGE is suspected. In our cohort, stool culture had a very low yield of detecting an underlying pathogen. Although patients who had stool cultures obtained were more likely to be febrile and to have a longer length of hospital stay than were those who did not have stool cultures, for the vast majority of patients, stool culture played little to no role in patient management. Further studies are needed to which patients benefit most from undergoing stool culture.

Roles of Vegetable Surface Properties and Sanitizer Type on Annual Disease Burden of Rotavirus Illness by Consumption of Rotavirus-Contaminated Fresh Vegetables: A Quantitative Microbial Risk Assessment

Enteric viruses are often detected in water used for crop irrigation. One concern is foodborne viral disease via the consumption of fresh produce irrigated with virus-contaminated water. Although the food industry routinely uses chemical sanitizers to disinfect post-harvest fresh produce, it remains unknown how sanitizer and fresh produce properties affect the risk of viral illness through fresh produce consumption. A quantitative microbial risk assessment model was conducted to estimate (i) the health risks associated with consumption of rotavirus (RV)-contaminated fresh produce with different surface properties (endive and kale) and (ii) how risks changed when using peracetic acid (PAA) or a surfactant-based sanitizer. The modeling results showed that the annual disease burden depended on the combination of sanitizer and vegetable type when vegetables were irrigated with RV-contaminated water. Global sensitivity analyses revealed that the most influential factors in the disease burden were RV concentration in irrigation water and postharvest disinfection efficacy. A postharvest disinfection efficacy of higher than 99% (2-log₁₀ ) was needed to decrease the disease burden below the World Health Organization (WHO) threshold, even in scenarios with low RV concentrations in irrigation water (i.e., river water). All scenarios tested here with at least 99.9% (3-log₁₀ ) disinfection efficacy had a disease burden lower than the WHO threshold, except for the endive treated with PAA. The disinfection efficacy for the endive treated with PAA was only about 80%, leading to a disease burden 100 times higher than the WHO threshold. These findings should be considered and incorporated into future models for estimating foodborne viral illness risks.

Bimodal Release Ondansetron for Acute Gastroenteritis Among Adolescents and Adults: A Randomized Clinical Trial

IMPORTANCE

Vomiting resulting from acute gastroenteritis is commonly treated with intravenous antiemetics in acute care settings. If oral treatment were beneficial, patients might not need intravenous administered hydration or medication. Furthermore, a long-acting treatment could provide sustained relief from nausea and vomiting.

OBJECTIVE

To determine whether an experimental long-acting bimodal release ondansetron tablet decreases gastroenteritis-related vomiting and eliminates the need for intravenous therapy for 24 hours after administration.

DESIGN, SETTING, AND PARTICIPANTS

This placebo-controlled, double-blind, randomized clinical trial included patients from 19 emergency departments and 2 urgent care centers in the United States from December 8, 2014, to February 17, 2017. Patients 12 years and older with at least 2 vomiting episodes from presumed gastroenteritis in the previous 4 hours and symptoms with less than 36 hours' duration were randomized using a 3:2 active to placebo ratio. Analyses were performed on an intent-to-treat basis and conducted from June 1, 2017, to November 1, 2017.

INTERVENTION

Bimodal release ondansetron tablet containing 6 mg of immediate release ondansetron and 18 mg of a 24-hour release matrix for a total of 24 mg of ondansetron.

MAIN OUTCOMES AND MEASURES

Treatment success was defined as no further vomiting, no need for rescue medication, and no intravenous hydration for 24 hours after bimodal release ondansetron administration.

RESULTS

Analysis included 321 patients (mean [SD] age, 29.0 [11.1] years; 195 [60.7%] women), with 192 patients in the bimodal release ondansetron group and 129 patients in the placebo group. Treatment successes were observed in 126 patients in the bimodal release ondansetron group (65.6%) compared with 70 patients in the placebo group (54.3%), with an 11.4% (95% CI, 0.3%-22.4%) absolute probability difference. The proportion of treatment success was 21% higher among patients who received bimodal release ondansetron compared with those who received a placebo (relative risk, 1.21; 95% CI, 1.00-1.46; P = .04). In an analysis including only patients with a discharge diagnosis of acute gastroenteritis and no major protocol violations, there were 123 treatment successes (69.5%) in the bimodal release ondansetron group compared with 67 treatment successes (54.9%) in the placebo group (relative risk, 1.27; 95% CI, 1.05-1.53; P = .01). Adverse effects were infrequent and similar to the known safety profile of ondansetron.

CONCLUSIONS AND RELEVANCE

This randomized clinical trial found that a long-acting bimodal release oral ondansetron tablet was an effective antiemetic among adolescents and adults with moderate to severe vomiting from acute gastroenteritis. The drug benefits extended to 24 hours after administration. Bimodal release ondansetron may decrease the need for intravenous access and emergency department care to manage acute gastroenteritis.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT02246439.

Incidence and etiology of infectious diarrhea from a facility-based surveillance system in Guatemala, 2008-2012

BACKGROUND

Diarrhea is a major cause of morbidity and mortality, yet incidence and etiology data are limited. We conducted laboratory-based diarrhea surveillance in Guatemala.

METHODS

A diarrhea case was defined as ≥3 loose stools in a 24-h period in a person presenting to the surveillance facilities. Epidemiologic data and stool specimens were collected. Specimens were tested for bacterial, parasitic, and viral pathogens. Yearly incidence was adjusted for healthcare seeking behaviors determined from a household survey conducted in the surveillance catchment area.

RESULTS

From November 2008 to December 2012, the surveillance system captured 5331 diarrhea cases; among these 1381 (26%) had specimens tested for all enteric pathogens of interest. The adjusted incidence averaged 659 diarrhea cases per 10,000 persons per year, and was highest among children aged < 5 years, averaging 1584 cases per 10,000 children per year. Among 1381 (26%) specimens tested for all the pathogens of interest, 235 (17%) had a viral etiology, 275 (20%) had a bacterial, 50 (4%) had parasites, and 86 (6%) had co-infections. Among 827 (60%) specimens from children aged < 5 years, a virus was identified in 196 (23%) patients; 165 (20%) had norovirus and 99 (12%) rotavirus, including co-infections. Among 554 patients aged ≥5 years, 103 (19%) had a bacterial etiology, including diarrheagenic Escherichia coli in 94 (17%) cases, Shigella spp. in 31 (6%), Campylobacter spp. in 5 (1%), and Salmonella spp. in 4 (1%) cases. Detection of Giardia and Cryptosporidium was infrequent (73 cases; 5%).

CONCLUSIONS

There was a substantial burden of viral and bacterial diarrheal diseases in Guatemala, highlighting the importance of strengthening laboratory capacity for rapid detection and control and for evaluation of public health interventions.

Risk factors for contagious gastroenteritis in adult patients with diarrhoea in the emergency department - a prospective observational multicentre study

Background

Infectious gastroenteritis is common in the emergency department (ED). Patients infected with either Norovirus or toxigenic Clostridium difficile require special isolation procedures. The aims were to describe the aetiology of infectious gastroenteritis in the ED, evaluate whether current isolation procedures, based on clinical judgement are sufficient, and to identify information that might be used to identify patients requiring isolation.

Methods

Prospective, observational, multicentre study. We collected information on symptoms, vital signs, travel history, the recent use of antibiotics, and infectious contacts and tested faecal samples for Norovirus, C. difficile, and enteropathogenic bacteria.

Results

The study enrolled 227 patients, of whom 163 (71%) delivered a faecal sample for Norovirus analysis (13% positive), 171 (74%) for C. difficile (13% positive), and 173 (76%) for enteropathogenic bacteria (16% positive). In total 71% of the patients were isolated using strict precautions, 29% of the isolated patient and 14% of the patients who were not isolated had had a highly contagious GE. Risk factors for Norovirus included frequent vomiting (OR 5.5), recent admission of another patient with Norovirus (OR 2.6), and a short duration of diarrhoea. Risk factors for C. difficile infections included older age (OR 6.0), longer duration of diarrhoea (OR 5.2), mucus in stool (OR 3.5), and previous antibiotic use (OR 23.4).

Conclusion

Highly contagious GE occurs in ¼ of the GE patients in the EDs, isolation based on clinical judgement is not very efficient. Several risk factors can predict the presence of Norovirus or toxigenic Clostridium difficile. It is uncertain whether this knowledge can improve isolation practices in ED settings.

Trial registration

This study was retrospectively registered in the Clinical Trials Data Base (NCT02685527) and prospectively approved by the Regional Committees on Health Research Ethics for Southern Denmark (project ID S20140200) and Ethics Committee at the Medical Association of Schleswig-Holstein [“Ethikkommission bei der Ärztekammer Schleswig-Holstein”, project ID 120/15(I)] and registered with the Danish Data Protection Agency (project ID nr. 2008-58-0035/ 1608).

Evaluation of rectal swab use for the determination of enteric pathogens: a prospective study of diarrhoea in adults

OBJECTIVES

A stool sample is the sample of choice for microbiological testing of enteric pathogens causing diarrhoea, but a rectal swab can be a more practical alternative. A prospective observational study was performed to evaluate the diagnostic performance of flocked rectal swab specimens using the syndromic molecular approach to determine the aetiology of diarrhoea in adults.

METHODS

We compared the performance of rectal swabs with stool samples as the reference standard in determining viral, bacterial and protozoal pathogens using real-time multiplex PCR as well as standard stool culture. Paired samples of stool and rectal swab specimens were collected from 304 adult patients with diarrhoea, presented at the Department of Infectious Diseases, University Medical Centre Ljubljana, between June 2016 and August 2017.

RESULTS

Overall sensitivity of rectal swab samples in the syndromic molecular approach was 83.2% (95% CI 77.2%-88.1%). Pathogen group-specific analysis of rectal swabs showed sensitivity of 65.6% (95% CI 52.7%-77.1%) for viruses and 57.1% (95% CI 28.9%-82.3%) for parasites. For bacteria, sensitivity was 86.5% (95% CI 79.5%-91.8%) when PCR was performed and 61.4% (95% CI 52.4%-69.9%) when culture for bacteria was performed. Mean threshold cycle (Ct) values for most pathogens were higher in rectal swab specimens than in stool specimens.

CONCLUSIONS

Our results indicate that rectal swabs can be used in the diagnosis of diarrhoea in adults when stool specimens are not available or when rapid aetiological determination is needed. However, rectal swabs should be analysed using a molecular approach. The mean Ct value for most pathogens is higher in rectal swab specimens than in stool specimens.

Cryptosporidium and Giardia in Wastewater and Surface Water Environments

and spp. are significant contributors to the global waterborne disease burden. Waterways used as sources of drinking water and for recreational activity can become contaminated through the introduction of fecal materials derived from humans and animals. Multiple studies have reported the occurence or concentrations of these pathogens in the environment. However, this information has not been comprehensively reviewed. Quantitative microbial risk assessment (QMRA) for and can be beneficial, but it often relies on the concentrations in environmental sources reported from the literature. A thorough literature review was conducted to develop an inventory of reported and concentrations in wastewater and surface water available in the literature. This information can be used to develop QMRA inputs. and (oo)cyst concentrations in untreated wastewater were up to 60,000 oocysts L and 100,000 cysts L, respectively. The maximum reported concentrations for and in surface water were 8400 oocysts L and 1000 cysts L, respectively. A summary of the factors for interpretation of concentration information including common quantification methods, survival and persistence, biofilm interactions, genotyping, and treatment removal is provided in this review. This information can help in identifying assumptions implicit in various QMRA parameters, thus providing the context and rationale to guide model formulation and application. Additionally, it can provide valuable information for water quality practitioners striving to meet the recreational water quality or treatment criteria. The goal is for the information provided in the current review to aid in developing source water protection and monitoring strategies that will minimize public health risks.

Inactivation Mechanisms of Human and Animal Rotaviruses by Solar UVA and Visible Light

Two rotavirus (RV) strains (sialidase-resistant Wa and sialidase-sensitive OSU) were irradiated with simulated solar UVA and visible light in sensitizer-free phosphate buffered solution (PBS) (lacking exogenous reactive oxygen species (ROS)) or secondary effluent wastewater (producing ROS). Although light attenuated for up to 15% through the secondary effluent wastewater (SEW), the inactivation efficacies increased by 0.7 log₁₀ for Wa and 2 log₁₀ for OSU compared to those in sensitizer-free phosphate buffered solution (PBS) after 4 h of irradiation. A binding assay using magnetic beads coated with porcine gastric mucin containing receptors for rotaviruses (PGM-MB) was developed to determine if inactivation influenced RV binding to its receptors. The linear correlation between the reduction in infectivity and the reduction in binding after irradiation in sensitizer-free solution suggests that the main mechanism of RV inactivation in the absence of exogenous ROS was due to damage to VP8*, the RV protein that binds to host cell receptors. For a given reduction in infectivity, greater damage in VP8* was observed with sialidase-resistant Wa compared to sialidase-sensitive OSU. The lack of correlation between the reduction in infectivity and the reduction in binding, in SEW, led us to include RNase treatment before the binding step to quantify virions with intact protein capsids and exclude virions that can bind to the receptors but have their capsid permeable after irradiation. This assay showed a linear correlation between the reduction in RV infectivity and RV-receptor interactions, suggesting that RV inactivation in SEW was due to compromised capsid proteins other than the VP8* protein. Thus, rotavirus inactivation by UVA and visible light irradiation depends on both the formation of ROS and the stability of viral proteins.

Molecular epidemiology of genogroup II norovirus infections in acute gastroenteritis patients during 2014-2016 in Pudong New Area, Shanghai, China

BACKGROUND

Norovirus (NoV), a member of the Caliciviridae, is now recognized as the leading cause of acute gastroenteritis (AGE) worldwide. Globally, the GII.4 Sydney_2012 variant has predominated in NoV-related AGE since 2012, although the novel variant GII.17 has also been reported as responsible for gastroenteritis outbreaks in East Asia since 2014. This study aimed to disclose the recent genotype patterns of NoV genogroup II (GII) presenting in AGE patients in Pudong New Area of Shanghai through a laboratory-based syndromic surveillance system. The study further aimed to delineate the predominant strains circulating in the population.

METHODS

Pudong New Area is located in eastern Shanghai and covers 20.89% of the Shanghai population. The laboratory-based syndromic surveillance system is composed of 12 sentinel hospitals among the 68 general hospitals in this area. AGE patients who sought medical care were sampled following an AGE surveillance protocol. Stool samples were collected from participating patients, and a standardized questionnaire was given to each patient by trained nurses to gain information on the disease profiles and demographics of the patients. Real-time reverse transcription polymerase chain reaction (qRT-PCR) was used to screen the GI nd GII NoV and RT-PCR was used to amplify NoV GII partial capsid protein open reading frame 2 (ORF2). NoV Genotyping Tool (version 1.0, RIVM, MA Bilthoven, Netherlands) was used for genotyping, and a phylogenetic analysis was conducted by MEGA 7.0.

RESULTS

During 2014-2016, among the 2069 virus-infected AGE cases, 65.88% were caused by NoV. NoV-AGE occurred most frequently in the periods from October to March. The patients with more severe diarrheal symptoms and vomiting were more likely to be infected by NoV. The main genotypes were GII.17 (44.69%) and GII.4 (39.26%), which dominated the NoV-AGE epidemics jointly or in turn, whereas a slight increase in GII.2 was observed beginning in May 2016. The GII.17 strains tended to cluster more with the Hu/JP/2014/GII.P17_GII.17/Kawasaki323 variants, representing novel prevalent strains. Among the GII.4 strains, the GII.4 Sydney_2012 variant was still the predominant strain.

CONCLUSIONS

NoV GII has become the main cause of virus-infected AGE in Pudong New Area, Shanghai. The predominant genotypes of NoV GII were GII.17 and GII.4. Comprehensive laboratory-based surveillance is important for clinical diagnosis and treatment. Identification of emerging new genotypes is also crucial for the prevention and control of NoV-infected AGE.

Enteric Viruses in Surface Waters from Argentina: Molecular and Viable-Virus Detection

Water resources contaminated with wastewater are an important source for the dissemination of enteric viruses with an impact on the health of the population. The aim of the study was to assess the viral contamination of freshwater from a dam in Argentina by using infectious enterovirus detection, viral RNA amplification, and a genetic characterization of five enteric viruses associated with diarrhea and hepatitis. Enterovirus infectivity (iEV) was evaluated by cell culture and direct immunofluorescence. The detection of the viral genome of rotavirus (RV), human astrovirus (HAstV), norovirus (NoV), hepatitis A virus (HAV), and hepatitis E virus (HEV) was performed by reverse transcriptase PCR (RT-PCR). A total of 48 water samples from 4 monitoring points on the body of the dam from January to December 2012 and 66 water samples from 3 tourist beaches on the edge of the dam from October 2013 to October 2015 were collected monthly. During the first period, the overall viral frequency detection was 52.1% for group A RV, 50% for HAstV, 60.4% for NoV, 22.9% for HAV, 2.1% for HEV, and 64.6% for iEV. The overall frequency detection for the second sampling was 18.2% for RV and HAstV, 31.8% for NoV, 7.57% for HEV, and 66.7% for iEV. There was no detection of HAV during this period. The genotypes and genogroups detected through the study correlated with the most common genomic variants associated with human gastrointestinal and hepatitis illnesses. The results obtained could alert the health systems and environmental sanitation to make decisions for viral control and prevention in our environment.IMPORTANCE The study shows the impact of anthropic contamination of one of the most important tourist water resources in Argentina. This course of recreational water would be a favorable scenario for infection, as well as a reservoir for the enteric viruses, creating a risk for the population exposed to these waters. The results obtained could alert the health systems and environmental sanitation to make decisions for the control and prevention of viral diseases in this environment.

Prevalence and Molecular Characterization of Campylobacter spp. Isolated from Patients with Diarrhea in Shunyi, Beijing

Bacterial pathogens have been confirmed as the major cause of acute diarrhea among outpatients in China. In this study, 370 stool samples from the patients aged from 15 to 87 years old with diarrhea were collected over 12 months (from May 2016 to April 2017) in two hospitals in Shunyi, Beijing. Bacterial isolation was performed for the common enteric pathogens: Campylobacter, Salmonella, Shigella, Diarrheagenic Escherichia coli, and Vibrio parahaemolyticus for 370 samples. The filtration method was used for the Campylobacter isolation in this study. The prevalence and molecular characterization of the Campylobacter were investigated. The isolation ratio for Campylobacter, Salmonella, Shigella, Diarrheagenic E. coli, and V. parahaemolyticus was 7.0% (26/370), 6.2% (23/370), 0.3% (1/370), 7.3% (27/370), and 10.3% (38/370), respectively. Based on the isolation result, Campylobacter positive cases presented in almost every month of the whole year and the isolation ratio was the highest among the tested pathogens during October to March. There was no significant difference between genders of Campylobacter positive cases. More Campylobacter positive cases presented dehydration compared with those who were positive for Salmonella. Twenty-six Campylobacter isolates were obtained in this study and 24 of these were Campylobacter jejuni. The antibiotic susceptibility tests indicated that 83.3% (20/24) of the isolates exhibited resistance to three or more types of antibiotic. Twenty STs were identified for the 26 Campylobacter isolates and four novel STs were identified in this study. No clonal cluster was found among these isolates. This is the first study for Campylobacter isolated using the filtration method in China which indicated the Campylobacter infection might be seriously under-ascertained in the diarrheal patients in China.

Infectious gastroenteritis and the need for strict contact precaution procedures in adults presenting to the emergency department: a Danish register-based study

BACKGROUND

Acute infectious gastroenteritis requires contact precautions to prevent spread. On acute admission, the cause of diarrhoea is unknown, so the decision regarding which patients to isolate has to be made on clinical information with a risk of inexpedient use of contact precautions.

AIM

To investigate how often gastroenteritis occurs (and therefore how often the need for isolation has to be assessed) in Danish emergency departments, and how often patients have to remain on contact precautions according to the results of faecal samples.

METHODS

This Danish register-based retrospective cohort study on adults in Danish emergency departments used three data sources: discharge diagnoses from the Danish National Patient Register; microbiological results from faecal samples provided in the emergency department; and the causes of hospital admission based on the chief complaint.

FINDINGS

Among 66,885 acute admissions, 4.3% of patients had at least one feature of gastroenteritis: admission with diarrhoea as the chief complaint (1.6%); microbiological examination of faecal sample (2.8%); and discharged with a diagnosis of gastroenteritis (1.7%). Nineteen percent of those who had a faecal sample tested were found to have norovirus or Clostridium difficile, and needed to remain on strict contact precautions.

CONCLUSION

The initiation of contact precautions has to be assessed for 4.3% of all emergency department patients; 19% of the patients who had a faecal sample tested had highly contagious gastroenteritis and required strict contact precautions. Further studies are needed to develop tools to determine which patients to isolate.

Norovirus Loads in Stool Specimens of Cancer Patients with Norovirus Gastroenteritis

In immunocompromised patients with norovirus (NoV) gastroenteritis, the relationship between fecal NoV load and clinical complications has not been examined. In this study, a validated real-time quantitative PCR assay was used to determine viral loads for NoV genogroup I and II (GI and GII) in NoV-positive stool specimens of cancer patients. A total of 234 specimens from 152 patients were positive for NoV, including 201 of GII and 33 of GI. Geometric mean of logarithmic copies per gram of stool (w/w) of NoV-GII were 9.03 ± 1.71 (means ± SD), which was significantly higher than that of NoV-GI [7.87 ± 1.49; odd ratio (OR), 3.22; 95% CI, 1.33-7.76; P = 0.009]. Among 152 patients with gastroenteritis, the fecal NoV geometric mean of logarithmic copy was correlated with mild (n = 85; 7.97 ± 1.55), moderate (n = 23; 9.09 ± 1.38), and severe (n = 44; 10.39 ± 0.91) episodes of severity by modified Vesikari scoring system, respectively. Multivariate analysis revealed that high level of NoV load was correlated with GII infections (OR, 4.13; 95% CI, 1.62-10.55; P = 0.003) and associated with development of severe clinical symptom (OR, 5.53; 95% CI, 2.00-7.24; P = 0.001) at the time of diagnosis. Infection with GII strains was more common than GI infection in cancer patients with viral gastroenteritis.

Enteropathogen detection in children with diarrhoea, or vomiting, or both, comparing rectal flocked swabs with stool specimens: an outpatient cohort study

BACKGROUND

Enteropathogen detection traditionally relies on diarrhoeal stool samples, but these are inconvenient to collect if they are not immediately available, leading to suboptimum return rates of samples and delayed or missed diagnostic opportunities. We sought to compare the enteropathogen yields of rectal swabs and stool specimens in children with diarrhoea or vomiting, or both.

METHODS

The Alberta Provincial Pediatric EnTeric Infection TEam (APPETITE) did a study in three outpatient cohorts in Calgary and Edmonton (AB, Canada)-children enrolled in the Pediatric Emergency Research Canada emergency departments, children receiving routine vaccinations at a Calgary health clinic, and symptomatic children who met criteria for treatment at home. Eligible participants were children younger than 18 years, with at least three episodes of vomiting or diarrhoea in the preceding 24 h and fewer than 7 days of symptoms. After excluding those enrolled within the previous fortnight, unable to follow-up, or having psychiatric illness, neutropenia, or requiring emergent care, we attempted to collect rectal swabs and stool from all participants. Specimens were tested with the multianalyte assay Luminex xTAG Gastrointestinal Pathogen Panel, an in-house five-virus panel and bacterial culture. Primary outcomes were comparative yield (calculated as the proportion of submitted paired specimens only in which at least one pathogen was identified) and overall yield (which calculated the proportion of study participants in whom at least one pathogen was identified in all specimens, where unsubmitted specimens were analysed as negative). We used McNemar's test to do pathogen-specific analyses, and generalised estimating equations (GEE) for the global (ie, any) pathogen analyses, with adjustments made for the presence of diarrhoea, location, and their interactions with specimen type.

FINDINGS

Between Dec 12, 2014, and Aug 31, 2016, we studied 1519 eligible participants, 1147 (76%) of whom provided stool specimens and 1514 (>99%) provided swab specimens. 871 (76%) of 1147 stool specimens and 1024 (68%) of 1514 swabs were positive for any pathogen (p<0·0001). Comparative yield adjusted odds ratios (ORs) for stool specimens relative to swabs were 1·24 (95% CI 1·11-1·38) in children with diarrhoea at presentation and 1·76 (1·47-2·11) in children without diarrhoea. GEE analysis identified an interaction between the presence of diarrhoea and specimen type (p=0·0011) and collection location (p=0·0078). In an overall yield analysis, pathogen yield was 57% (871 of 1519 children) for stool specimens and 67% (1024 of 1519 children) for rectal swabs, with an unadjusted OR of 0·65 (95% CI 0·59-0·72) for stool relative to swab.

INTERPRETATION

Rectal swabs should be done when enteropathogen identification and rapid detection are needed, appropriate molecular diagnostic technology is available, and a stool specimen is not immediately available. In view of their high yield, we urge that the recommendation against the use of rectal swabs as diagnostic specimens be reconsidered.

FUNDING

Alberta Innovates-Health Solutions Team Collaborative Research Innovation Opportunity.

Association between glycaemic control and common infections in people with Type 2 diabetes: a cohort study

AIM

To investigate the impact of glycaemic control on infection incidence in people with Type 2 diabetes.

METHODS

We compared infection rates during 2014 in people with Type 2 diabetes and people without diabetes in a large primary care cohort in the UK (the Royal College of General Practitioners Research and Surveillance Centre database). We performed multilevel logistic regression to investigate the impact of Type 2 diabetes on presentation with infection, and the effect of glycaemic control on presentation with upper respiratory tract infections, bronchitis, influenza-like illness, pneumonia, intestinal infectious diseases, herpes simplex, skin and soft tissue infections, urinary tract infections, and genital and perineal infections. People with Type 2 diabetes were stratified by good [HbA_1c < 53 mmol/mol (< 7%)], moderate [HbA_1c 53-69 mmol/mol (7-8.5%)] and poor [HbA_1c > 69 mmol/mol (> 8.5%)] glycaemic control using their most recent HbA_1c concentration. Infection incidence was adjusted for important sociodemographic factors and patient comorbidities.

RESULTS

We identified 34 278 people with Type 2 diabetes and 613 052 people without diabetes for comparison. The incidence of infections was higher in people with Type 2 diabetes for all infections except herpes simplex. Worsening glycaemic control was associated with increased incidence of bronchitis, pneumonia, skin and soft tissue infections, urinary tract infections, and genital and perineal infections, but not with upper respiratory tract infections, influenza-like illness, intestinal infectious diseases or herpes simplex.

CONCLUSIONS

Almost all infections analysed were more common in people with Type 2 diabetes. Infections that are most commonly of bacterial, fungal or yeast origin were more frequent in people with worse glycaemic control.

Genomics and Foodborne Viral Infections

Foodborne viral illness, resulting from the consumption of contaminated food or water containing pathogenic viruses, remains a major public health problem globally with substantial economic impact. Major challenges regarding recognizing, detecting, characterizing, and effectively responding to foodborne viral threats to health exist. Adequate health crisis management is largely dependent on early detection of potential public health threats, which is hampered by changing trends in disease outbreaks, from localized clusters of disease in confined populations to dispersed outbreaks with excellent opportunity for further transmission. In addition, no precise and consistent global baseline syndrome and diagnostic surveillance information exists. An integrated multidisciplinary approach with a combination of sustained pathogen syndrome and diagnostic surveillance, genomics-based, and standardized global analytical networks gathering clinical, epidemiological and genetic data alike would be required to understand the dynamics of foodborne viral infection and to mitigate potential effects of future threats. A huge global effort in virus syndrome and diagnostic surveillance may be justified in the light of global health impact in general, and timely with the development of new metagenomics tools that hold the promise of not only identifying viral pathogens, but possibly the complete microbiome in a single assay.

The equity of China's emergency medical services from 2010-2014

Background

With the depth development of health care system reform in China, emergency medical services (EMS) is confronted with challenges as well as opportunities. This study aimed to analyze the equity of China’s EMS needs, utilization, and resources distribution, and put forward proposal to improve the equity.

Method

Three emergency needs indicators (mortality rate of cardiovascular and cerebrovascular diseases, harm, and digestive system disease), two utilization indicators (emergency outpatient visits and rate of utilization) and one resource allocation indicator (number of EMS facilities) were collected after the review of the China Statistical Yearbook and the National Disease Surveillance System. Next, EMS related indicators were compared among 31 provinces from the eastern, central, and western regions of the country. Concentration Index (CI) were used to measure the equity of EMS needs and utilization among the western, central, and eastern regions. The Gini coefficient of demographic and geographic distribution of facilities represented the equity of resource allocation.

Result

During 2010–2014, the CI of cardiovascular and cerebrovascular disease mortality changed from positive to negative, which indicates that the concentrated trend transferred from richer regions to the poorer area. Injury mortality (CI: range from − 0.1241to −0.1504) and digestive disease mortality (CI: range from − 0.1921 to − 0.2279) consistently concentrated in the poorer region, and the inequity among regions became more obviously year-by-year. The utilization of EMS (CI: range from 0.1074 to 0.0824) showed an improvement; however, the inequity reduced gradually. The EMS facilities distribution by population (Gini coefficient: range from 0.0922 to 0.1200) showed high equitability but the EMS facilities distribution by geography (Gini coefficient: range from 0.0922 to 0.1200) suggested a huge gap between regions because the Gini coefficients were greater than 0.5 in the past 5 years.

Conclusion

There are some inequities of needs, utilization, and resource allocation in the China EMS. The government needs to stick to the principle of increasing investment in poorer regions, perfecting ambulance configuration and improving health workers’ professional skills to improve the equity and quality of EMS.

Acute Gastroenteritis Viruses

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Acute diarrhea is the leading cause of morbidity and second commonest cause of mortality in children <5 years old worldwide.

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Most acute diarrheal illnesses are caused by viruses.

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Noroviruses are the commonest cause of diarrhea in all age groups combined, and rotaviruses are still the leading cause of diarrhea for children <5 years old.

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Transmission is mainly by the fecal–oral route through person-to-person contact, contaminated food and water.

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Most cases of viral diarrhea are mild and self-limiting, but severe cases occur, leading to dehydration and death. Repeated episodes lead to malnutrition.

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Most cases can be managed at home with oral rehydration solutions and feeding a regular diet.

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Vaccines will be the best preventive measure. Only rotavirus vaccines are available.

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Breast-feeding, vitamin A supplementation and zinc significantly reduce the frequency and/or severity of diarrhea.

Province-Wide Review of Pediatric Shiga Toxin-Producing Escherichia coli Case Management

OBJECTIVE

To identify the gaps in the care of children infected with Shiga toxin-producing Escherichia coli (STEC), we sought to quantitate care received and management timelines. Such knowledge is crucial to the design of interventions to prevent the development of hemolytic uremic syndrome (HUS).

STUDY DESIGN

We conducted a retrospective case-series study of 78 children infected with STEC in Alberta, Canada, through the linkage of microbiology and laboratory results, telephone health advice records, hospital charts, physician billing submissions, and outpatient antimicrobial dispensing databases. Outcomes were the time intervals between initial presentation and reporting of positive culture result and symptom onset to HUS and to describe the proportions that had baseline blood work performed and received antibiotics.

RESULTS

Seventy-eight children infected with STEC were identified; 13% (10/78) developed HUS. Median time from initial presentation to laboratory stool sample receipt was 33 hours (IQR 18, 42); time to positive culture was 120 hours (IQR 86, 205). Time from symptom onset to HUS diagnosis was 188 ± 37 hours. Baseline blood tests were obtained in 74% (58/78) of infected children. Antibiotics were administered to 50% (5/10) of those who developed HUS and 22% (15/78) of those who did not; P = .11. The provincial telephone advice system received 31 calls regarding 24 children infected with STEC; 23% (7/31) of callers were recommended to seek emergency department care.

CONCLUSIONS

A significant proportion of children developed HUS following multiple interactions with the health care system. Delays in the confirmation of STEC infection occurred. There are numerous opportunities to improve the timing, monitoring, and interventions in children infected with STEC.