A foodborne outbreak of gastroenteritis caused by Norovirus and Bacillus cereus at a university in the Shunyi District of Beijing, China 2018: a retrospective cohort study

Abstract Background On September 4, 2018, a boarding school in the Shunyi District of Beijing, China reported an outbreak of acute gastroenteritis. At least 209 suspected students caused of diarrhea and vomiting. The case was investigated, and control measures were taken to prevent further spread. Methods A retrospective cohort study was conducted among the school students and staff in order to test hypothesis that high risk of food served at the school canteen. We collected information on demographics, refectory records, person to person transmission by uniform epidemiological questionnaire. Risk ratios (RR) and 95% confidence intervals (CI) were calculated. Stool specimens of cases and canteen employees, retained food, water, and environmental swabs were investigated by laboratory analysis. Results We identified 209 cases (including 28 laboratory-confirmed cases) which occurred from August 29 to September 10. All cases were students, and the average age was 20, 52% were male. The outbreak lasted for 13 days, and peaked on September 5. Consumption of Drinks stall and Rice flour stall on September 1 (RR:3.4, 95%CI:1.5–7.8, and RR:7.6, 95%CI:2.8–20.2), Rice flour stall and Fish meal stall on September 2 (RR:4.0, 95%CI:1.2–13.6, and RR:4.6, 95%CI:1.7–12.5), muslim meal stall on September 4 (RR:2.7, 95%CI:1.3–5.4), Barbeque stall on September 5 (RR:3.0, 95%CI:1.2–7.0) were independently associated with increased risk of disease within the following 2 days. Among 35 specimens of rectal swabs or feces from students, 28 specimens were positive. Norovirus GI.6 alone was detected in 23 specimens, Bacillus cereus alone in 3 specimens and both norovirus GI.6 and Bacillus cereus in 2 specimens. Ten specimens of rectal swabs from canteen employees were positive for norovirus GI, and 2 specimens were positive for Bacillus cereus. Four retained food specimens were positive for Bacillus cereus, and environmental samples were negative for any viruses or bacteria. Conclusion Our investigation indicated that canteen employees were infected by two pathogens (norovirus and Bacillus cereus) and transmission may have been possible due to unhygienic practices. Student consumption of food or drink at high-risk stalls was determined as the probable cause of the outbreak.

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A foodborne outbreak of gastroenteritis caused by Norovirus and Bacillus cereus at a university in the Shunyi District of Beijing, China 2018: a retrospective cohort study

10.21203/rs.2.10129/v2 ◽

2019 ◽

Author(s):

Dongwan Chen ◽

Yongjin Li ◽

Jinchang Lv ◽

Xiufeng Liu ◽

Peng Gao ◽

...

Keyword(s):

Cohort Study ◽

High Risk ◽

Bacillus Cereus ◽

Retrospective Cohort Study ◽

Retrospective Cohort ◽

Rice Flour ◽

School Canteen ◽

Increased Risk ◽

Rectal Swabs ◽

Beijing China

Abstract Background On September 4, 2018, a boarding school in the Shunyi District of Beijing, China reported an outbreak of acute gastroenteritis. At least 209 suspected students caused of diarrhea and vomiting. The case was investigated, and control measures were taken to prevent further spread. Methods A retrospective cohort study was conducted among the school students and staff in order to test hypothesis that high risk of food served at the school canteen. We collected information on demographics, refectory records, person to person transmission by uniform epidemiological questionnaire. Risk ratios (RR) and 95% conﬁdence intervals (CI) were calculated. Stool specimens of cases and canteen employees, retained food, water, and environmental swabs were investigated by laboratory analysis. Results We identiﬁed 209 cases (including 28 laboratory-confirmed cases) which occurred from August 29 to September 10. All cases were students, and the average age was 20, 52% were male. The outbreak lasted for 13 days, and peaked on September 5. Consumption of Drinks stall and Rice flour stall on September 1 (RR:3.4, 95%CI:1.5-7.8, and RR:7.6, 95%CI:2.8-20.2), Rice flour stall and Fish meal stall on September 2 (RR:4.0, 95%CI:1.2-13.6, and RR:4.6, 95%CI:1.7-12.5), muslim meal stall on September 4 (RR:2.7, 95%CI:1.3-5.4), Barbeque stall on September 5 (RR:3.0, 95%CI:1.2-7.0) were independently associated with increased risk of disease within the following 2 days. Among 35 specimens of rectal swabs or feces from students, 28 specimens were positive. Norovirus GI.6 alone was detected in 23 specimens, Bacillus cereus alone in 3 specimens and both norovirus GI.6 and Bacillus cereus in 2 specimens. 10 specimens of rectal swabs from canteen employees were positive for norovirus GI, and 2 specimens were positive for Bacillus cereus. Four retained food specimens were positive for Bacillus cereus, and environmental samples were negative for any viruses or bacteria. Conclusion Our investigation indicated that canteen employees were infected by two pathogens (norovirus and Bacillus cereus) and transmission may have been possible due to unhygienic practices. Student consumption of food or drink at high-risk stalls was determined as the probable cause of the outbreak.

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A foodborne outbreak of gastroenteritis caused by Norovirus and Bacillus cereus at a university in the Shunyi District of Beijing, China 2018: a retrospective cohort study

10.21203/rs.2.10129/v3 ◽

2019 ◽

Author(s):

Dongwan Chen ◽

Yongjin Li ◽

Jinchang Lv ◽

Xiufeng Liu ◽

Peng Gao ◽

...

Keyword(s):

Cohort Study ◽

High Risk ◽

Bacillus Cereus ◽

Retrospective Cohort Study ◽

Retrospective Cohort ◽

Rice Flour ◽

School Canteen ◽

Increased Risk ◽

Rectal Swabs ◽

Beijing China

Abstract Background On September 4, 2018, a boarding school in the Shunyi District of Beijing, China reported an outbreak of acute gastroenteritis. At least 209 suspected students caused of diarrhea and vomiting. The case was investigated, and control measures were taken to prevent further spread. Methods A retrospective cohort study was conducted among the school students and staff in order to test hypothesis that high risk of food served at the school canteen. We collected information on demographics, refectory records, person to person transmission by uniform epidemiological questionnaire. Risk ratios (RR) and 95% conﬁdence intervals (CI) were calculated. Stool specimens of cases and canteen employees, retained food, water, and environmental swabs were investigated by laboratory analysis. Results We identiﬁed 209 cases (including 28 laboratory-confirmed cases) which occurred from August 29 to September 10. All cases were students, and the average age was 20, 52% were male. The outbreak lasted for 13 days, and peaked on September 5. Consumption of Drinks stall and Rice flour stall on September 1 (RR:3.4, 95%CI:1.5-7.8, and RR:7.6, 95%CI:2.8-20.2), Rice flour stall and Fish meal stall on September 2 (RR:4.0, 95%CI:1.2-13.6, and RR:4.6, 95%CI:1.7-12.5), muslim meal stall on September 4 (RR:2.7, 95%CI:1.3-5.4), Barbeque stall on September 5 (RR:3.0, 95%CI:1.2-7.0) were independently associated with increased risk of disease within the following 2 days. Among 35 specimens of rectal swabs or feces from students, 28 specimens were positive. Norovirus GI.6 alone was detected in 23 specimens, Bacillus cereus alone in 3 specimens and both norovirus GI.6 and Bacillus cereus in 2 specimens. 10 specimens of rectal swabs from canteen employees were positive for norovirus GI, and 2 specimens were positive for Bacillus cereus. Four retained food specimens were positive for Bacillus cereus, and environmental samples were negative for any viruses or bacteria. Conclusion Our investigation indicated that canteen employees were infected by two pathogens (norovirus and Bacillus cereus) and transmission may have been possible due to unhygienic practices. Student consumption of food or drink at high-risk stalls was determined as the probable cause of the outbreak.

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Progression of castrate-resistant (CR) disease in nonmetastatic (M0) prostate cancer (PC) patients: A retrospective cohort study using data from the Henry Ford Health System (HFHS).

Journal of Clinical Oncology ◽

10.1200/jco.2012.30.15_suppl.e15147 ◽

2012 ◽

Vol 30 (15_suppl) ◽

pp. e15147-e15147

Author(s):

Jennifer Beebe-Dimmer ◽

Karynsa Cetin ◽

Cecilia Yee ◽

Lois Lamerato ◽

Scott Stryker ◽

...

Keyword(s):

Cohort Study ◽

High Risk ◽

Retrospective Cohort Study ◽

Retrospective Cohort ◽

Specific Antigen ◽

Population Based ◽

Entire Cohort ◽

Increased Risk ◽

Diverse Patient Population

e15147 Background: Androgen deprivation therapy (ADT) is the cornerstone treatment of advanced PC, but is frequently used in the M0 setting. After a variable period of hormone-sensitivity, most patients develop CR disease (rising prostate-specific antigen [PSA] despite ongoing ADT). These men are at increased risk of developing bone metastases (BMT), particularly in those with higher serum PSA and shorter PSA doubling time (DT). The epidemiology and natural history of M0 CRPC has not been well-studied in a population-based setting. Methods: A retrospective cohort study was conducted using HFHS administrative data and included 691 men diagnosed with M0 PC between 1996 and 2005, who received ADT, with serial PSA measurements to determine CR. Patient records through 12/31/2008 were reviewed for outcomes of interest. CRPC was defined as 2 consecutive PSA rises, with “high risk” defined as PSA ≥8 ng/mL or PSA DT ≤10 months (mos) after the development of CRPC (Smith MR et al. Lancet 379:39-46, 2012). The risk of BMT was estimated for the entire cohort and for the CRPC and high-risk CRPC subsets. Results: Of the 691 patients included in the cohort (median age: 73 years, 48% African American), 98% received only GnRH agonists and 2% had orchiectomy. Median follow-up for the entire cohort after ADT initiation was 49 mos (IQR=45). 101 patients (15%) met criteria for CRPC during follow-up, with a median of 18 mos on active ADT prior to CRPC development (IQR=14). Of CRPC patients, 85% met criteria for high-risk (of those, 16% had PSA ≥8 ng/mL, 12% had PSA DT ≤10 mos, and 72% had both). Among all patients, 12% (n=82) developed BMT during follow-up, with 42% (n=36) of the high-risk CRPC subset developing BMT. Median time from high-risk CRPC to BMT was 9 mos (IQR=17). Conclusions: The HFHS resource allowed for our investigation of PSA characteristics corresponding to disease progression in a racially diverse patient population. A substantial proportion of M0 PC patients on ADT will eventually develop CR disease. Once a patient has CRPC, the risk of BMT is relatively high.

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Outcomes of COVID-19 contact tracing in hospital healthcare workers: a retrospective cohort study

Journal of the Pakistan Medical Association ◽

10.47391/jpma.3615 ◽

2021 ◽

Author(s):

Seyfi Durmaz ◽

Ece Fidan Kucuk ◽

Sera Simsek ◽

Kevser Durgun ◽

Emine Bilge Karakas ◽

...

Keyword(s):

Cohort Study ◽

High Risk ◽

Retrospective Cohort Study ◽

Retrospective Cohort ◽

Healthcare Workers ◽

Hospital Setting ◽

University Hospital ◽

Contact Tracing ◽

Specific Rate ◽

Increased Risk

Objective: To determine risk-group-specific rate of becoming COVID-19-positive among healthcare workers having had contact with COVID-19 cases. Methods: The retrospective cohort study was conducted at the Ege University Hospital, Bornova, Turkey, and comprised all healthcare workers who had come into contact with COVID-19 cases between March 11 and May 31, 2020. The contacts were classified as low-risk, medium-risk and high-risk using the guidelines of the Turkish Ministry of Health. The outcome measures were the incidence of infection among contacts and the incubation period and serial interval among the new cases. Data was analysed using SPSS 23. Results: Of the 845 cases, 312(37%) had high risk, 263(31%) medium and 270(32%) low. Overall, there were 490(58%) females, 355(41%) males, 565(67%) aged <40 years, and 277(33%) aged >40 years. Of the total, 27(3.20%) healthcare workers tested COVID-19-positive and distribution among the risk-based groups was significant (p=0.037). There was a significantly increased risk of incidence among repeated contacts, no mask use, and the source being a colleague (p<0.05). Conclusion: The detection of high-risk contacts was found to be important for controlling COVID-19 infection in a hospital setting. Key Words: SARS-CoV-2, Healthcare workers, Contact tracing, Contact-based surveillance. Continuous...

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A foodborne outbreak of gastroenteritis caused by Norovirus and Bacillus cereus at a university in the Shunyi District of Beijing, China 2018

10.21203/rs.2.10129/v1 ◽

2019 ◽

Author(s):

Dongwan Chen ◽

Yongjin Li ◽

Jinchang Lv ◽

Xiufeng Liu ◽

Peng Gao ◽

...

Keyword(s):

Bacillus Cereus ◽

Rice Flour ◽

High Rate ◽

School Students ◽

Hygiene Practices ◽

School Canteen ◽

Increased Risk ◽

Risk Of Disease ◽

Stool Samples ◽

Beijing China

Abstract Background On 4 September 2018, a boarding school in the Shunyi District of Beijing, China reported an outbreak of acute gastroenteritis. At least 209 affected students developed the symptoms of diarrhea and vomiting. Investigations were conducted to identify the agent and source of this outbreak, and to implement controls to prevent further transmission. Methods A retrospective cohort study was conducted among the school students and staff in order to test hypothesis that food served at the school canteen. We collected information on demographics, refectory records at the canteen and contact to ill persons or vomit, using a uniform epidemiological questionnaire. Risk ratios (RR) and 95% conﬁdence intervals (CI) were calculated. Stool specimens of cases and canteen employees, food served, water, and environmental swabs were investigated by laboratory analysis. Results We identiﬁed 209 cases(including 28 laboratory-confirmed cases) that occurred from August 29 to September 10. All cases were students, and the median age was 20 years, 52% were male. The outbreak lasted for 13 days, and peaked on September 5. Consumption of Drinks window and Rice flour window on 1 September(RR: 3.4, 95% CI: 1.5-7.8, and RR: 7.6, 95% CI: 2.8-20.2), Rice flour window and Fish meal window on 2 September(RR: 4.0, 95% CI: 1.2-13.6, and RR: 4.6, 95% CI: 1.7-12.5), Moslem meal window on 4 September(RR: 2.7, 95%CI: 1.3-5.4), Barbeque window on 5 September(RR: 3.0, 95%CI: 1.2-7.0) were independently associated with increased risk of disease within the following 2 days. Rectal swabs or stool samples from twenty-five cases and ten canteen employees were positive for norovirus GI.6. Five cases were positive for Bacillus cereus, among them, two stool samples were detected by a mixed infection of Norovirus and Bacillus cereus. Four retained food specimens were positive for Bacillus cereus, and environmental samples were negative for any viruses or bacteria. Conclusion Our investigation indicated that consumption of high-risk windows was the source of this outbreak. The high rate of infection of both pathogens was exacerbated by unhygienic manipulation and Inappropriate hygiene practices in canteen employees.

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Proton pump inhibitors versus histamine-2 receptor blockers for stress ulcer prophylaxis in patients with sepsis: a retrospective cohort study

Journal of International Medical Research ◽

10.1177/03000605211025130 ◽

2021 ◽

Vol 49 (6) ◽

pp. 030006052110251

Author(s):

Minqiang Huang ◽

Ming Han ◽

Wei Han ◽

Lei Kuang

Keyword(s):

Risk Factors ◽

Cohort Study ◽

Hospital Mortality ◽

Critically Ill ◽

Proton Pump ◽

Retrospective Cohort Study ◽

Retrospective Cohort ◽

Stress Ulcer ◽

Increased Risk ◽

Ulcer Prophylaxis

Objective We aimed to compare the efficacy and risks of proton pump inhibitor (PPI) versus histamine-2 receptor blocker (H2B) use for stress ulcer prophylaxis (SUP) in critically ill patients with sepsis and risk factors for gastrointestinal bleeding (GIB). Methods In this retrospective cohort study, we used the Medical Information Mart for Intensive Care III Clinical Database to identify critically ill adult patients with sepsis who had at least one risk factor for GIB and received either an H2B or PPI for ≥48 hours. Propensity score matching (PSM) was conducted to balance baseline characteristics. The primary outcome was in-hospital mortality. Results After 1:1 PSM, 1056 patients were included in the H2B and PPI groups. The PPI group had higher in-hospital mortality (23.8% vs. 17.5%), GIB (8.9% vs. 1.6%), and pneumonia (49.6% vs. 41.6%) rates than the H2B group. After adjusting for risk factors of GIB and pneumonia, PPI use was associated with a 1.28-times increased risk of in-hospital mortality, 5.89-times increased risk of GIB, and 1.32-times increased risk of pneumonia. Conclusions Among critically ill adult patients with sepsis at risk for GIB, SUP with PPIs was associated with higher in-hospital mortality and higher risk of GIB and pneumonia than H2Bs.

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Adverse Pregnancy Outcomes by Degree of Maternal Serum Analyte Elevation: A Retrospective Cohort Study

American Journal of Perinatology Reports ◽

10.1055/s-0040-1716741 ◽

2020 ◽

Vol 10 (04) ◽

pp. e369-e379

Author(s):

Amanda Yeaton-Massey ◽

Rebecca J. Baer ◽

Larry Rand ◽

Laura L. Jelliffe-Pawlowski ◽

Deirdre J. Lyell

Keyword(s):

Cohort Study ◽

Retrospective Cohort Study ◽

Retrospective Cohort ◽

Screening Program ◽

Maternal Serum ◽

Obstetric Complication ◽

Patient Counseling ◽

Increased Risk ◽

Antenatal Management ◽

Adverse Pregnancy

Abstract Objective The aim of this study was to evaluate rates of preterm birth (PTB) and obstetric complication with maternal serum analytes > 2.5 multiples of the median (MoM) by degree of elevation. Study Design Retrospective cohort study of singleton live-births participating in the California Prenatal Screening Program (2005–2011) examining PTB and obstetric complication for α-fetoprotein (AFP), human chorionic gonadotropin (hCG), unconjugated estriol (uE3), and inhibin A (INH) by analyte subgroup (2.5 to < 6.0, 6.0 to < 10.0, and ≥ 10.0 MoM vs. < 2.5 MoM). Results The risk of obstetric complication increased with increasing hCG, AFP, and INH MoM, and were greatest for AFP and INH of 6.0 to <10.0 MoM. The greatest risk of any adverse outcome was seen for hCG MoM ≥ 10.0, with relative risk (RR) of PTB < 34 weeks of 40.8 (95% confidence interval [CI]: 21.7–77.0) and 13.8 (95% CI: 8.2–23.1) for obstetric complication. Conclusions In euploid, structurally normal fetuses, all analyte elevations > 2.5 MoM confer an increased risk of PTB and, except for uE3, obstetric complication, and risks for each are not uniformly linear. These data can help guide patient counseling and antenatal management.

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Delayed adjuvant imatinib in patients with high risk of recurrence of gastrointestinal stromal tumor after radical surgery: a retrospective cohort study

Journal of Cancer Research and Clinical Oncology ◽

10.1007/s00432-021-03749-6 ◽

2021 ◽

Author(s):

Wan Qianyi ◽

Xu Mei ◽

Zhao Rui ◽

Wang Yong ◽

Wu Yutao ◽

...

Keyword(s):

Cohort Study ◽

High Risk ◽

Gastrointestinal Stromal Tumor ◽

Retrospective Cohort Study ◽

Retrospective Cohort ◽

Radical Surgery ◽

Stromal Tumor ◽

Adjuvant Imatinib ◽

Risk Of Recurrence

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Colorectal Cancer Risk in Women with Gynecologic Cancers—A Population Retrospective Cohort Study

Journal of Clinical Medicine ◽

10.3390/jcm10143127 ◽

2021 ◽

Vol 10 (14) ◽

pp. 3127

Author(s):

Szu-Chia Liao ◽

Hong-Zen Yeh ◽

Chi-Sen Chang ◽

Wei-Chih Chen ◽

Chih-Hsin Muo ◽

...

Keyword(s):

Colorectal Cancer ◽

Ovarian Cancer ◽

Cervical Cancer ◽

Cohort Study ◽

Cancer Patients ◽

Retrospective Cohort Study ◽

Retrospective Cohort ◽

Gynecologic Cancer ◽

Ovarian Cancers ◽

Increased Risk

We conducted a retrospective cohort study to evaluate the subsequent colorectal cancer (CRC) risk for women with gynecologic malignancy using insurance claims data of Taiwan. We identified patients who survived cervical cancer (N = 25,370), endometrial cancer (N = 8149) and ovarian cancer (N = 7933) newly diagnosed from 1998 to 2010, and randomly selected comparisons (N = 165,808) without cancer, matched by age and diagnosis date. By the end of 2011, the incidence and hazard ratio (HR) of CRC were estimated. We found that CRC incidence rates were 1.26-, 2.20-, and 1.61-fold higher in women with cervical, endometrial and ovarian cancers, respectively, than in comparisons (1.09/1000 person–years). The CRC incidence increased with age. Higher adjusted HRs of CRC appeared within 3 years for women with endometrial and ovarian cancers, but not until the 4th to 7th years of follow up for cervical cancer survivals. Cancer treatments could reduce CRC risks, but not significantly. However, ovarian cancer patients receiving surgery alone had an incidence of 3.33/1000 person–years for CRC with an adjusted HR of 3.79 (95% CI 1.11–12.9) compared to patients without any treatment. In conclusion, gynecologic cancer patients are at an increased risk of developing CRC, sooner for those with endometrial or ovarian cancer than those with cervical cancer.

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