An outbreak of calicivirus associated with consumption of 
frozen raspberries

In April 1988, an outbreak of gastroenteritis occurred among employees in a large company in Helsinki, Finland. A retrospective cohort study, using a self-administered questionnaire, was carried out to ascertain the cause and extent of the outbreak. To meet the case definition, employees had to have had diarrhoea and/or vomiting since 2 April, 1998. A subanalysis was made in the biggest office, consisting of 360 employees, of whom 204 (57%) completed the questionnaire. Of these 108 (53%) met the case definition. Employees who had eaten raspberry dressing were more likely to meet the case definition than those who had not (Attack Rate (AR) 65% versus AR 18% Relative Risk, (RR) 3·7, 95%, Confidence Intervals (CI) 2·0–6·7). Four stool specimens obtained from affected kitchen staff who had all eaten the raspberry dressing and who had all become ill simultaneously with the employees were positive by polymerase chain reaction (PCR) for calicivirus. The data suggest that the primary source of the outbreak was imported frozen raspberries contaminated by calicivirus.

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Virus Load and Incidence Olfactory, Gustatory, Respiratory, Gastrointestinal Disorders in COVID-19 Patients: A Retrospective Cohort Study

10.22541/au.161635941.12859469/v1 ◽

2021 ◽

Author(s):

Mohammad Hosein Taziki Balajelini ◽

Abdolhalim Rajabi ◽

Masoud Mohammadi ◽

Hadi Razavi Nikoo ◽

Alijan Tabarraei ◽

...

Keyword(s):

Polymerase Chain Reaction ◽

Cohort Study ◽

Viral Load ◽

Retrospective Cohort Study ◽

Retrospective Cohort ◽

Gastrointestinal Symptoms ◽

Chain Reaction ◽

Ct Value ◽

The Mean ◽

Polymerase Chain

Objectives: This study investigated the relationship between viral load and the incidence and recovery of olfactory and gustatory dysfunction (OD and GD), incidence of respiratory and gastrointestinal symptoms in COVID-19 patients. Design: A Retrospective Cohort Study. Setting and Participants: In total 599 outpatients’ cases polymerase chain reaction (PCR)–confirmed COVID-19-positive patients in Golestan province were included in the study. Main Outcome Measures: The incidence of OD, GD, their severity and the time of recovery was determined. The association of these variables with cycle threshold (CT) values of SARS-CoV-2 polymerase chain reaction was assessed. Results: The mean age of patients was 38.27 ± 13.62 years. The incidence of general symptoms included myalgia 70.1%, headache 51.8%, fever 47.7%, and dyspnea 21.4%. 41.9% of patients had gastrointestinal symptoms, including abdominal pain 26.5%, diarrhea 25.2%, nausea 20.5%, and vomiting 12.9%. 12.2% of patients had comorbidity. The trimester recovery rates of OD and GD were 93.94% and 94.74%, respectively. The mean recovery time of OD and GD was 14.56±13.37 and 13.8±3.77 days, respectively. The mean CT value in all patients was 27.45±4.55. There were significant associations between CT value with headache (P=0.04), GD (P=0.002) and OD (P=0.001). Conclusions: The intensity and the recovery of OD and GD in Covid-19 patients may be affected by initial viral load. Unlike to respiratory and gastrointestinal symptoms, the OD and GD were associated with lower viral load. Therefore, it may be recommended to use these clinical symptoms as an indicator in the initial screening of patients during pandemics.

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The association between real-time reverse transcriptase polymerase chain reaction cycle threshold values, symptoms and disease severity among COVID-19 patients in the community: a retrospective cohort study

Infectious Diseases ◽

10.1080/23744235.2021.1998606 ◽

2021 ◽

pp. 1-8

Author(s):

Maya Makov-Assif ◽

Sydney Krispin ◽

Yatir Ben-Shlomo ◽

Tal Holander ◽

Noa Dagan ◽

...

Keyword(s):

Polymerase Chain Reaction ◽

Cohort Study ◽

Reverse Transcriptase ◽

Retrospective Cohort Study ◽

Retrospective Cohort ◽

Threshold Values ◽

Polymerase Chain Reaction Cycle ◽

Chain Reaction ◽

Reaction Cycle ◽

Polymerase Chain

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Polymerase chain reaction amplification and typing of rotavirus in environmental samples

Water Science & Technology ◽

10.2166/wst.1995.0643 ◽

1995 ◽

Vol 31 (5-6) ◽

pp. 371-374 ◽

Cited By ~ 5

Author(s):

R. Gajardo ◽

R. M. Pintó ◽

A. Bosch

Keyword(s):

Polymerase Chain Reaction ◽

Environmental Samples ◽

Polymerase Chain Reaction Amplification ◽

Rt Pcr ◽

Chain Reaction ◽

Pcr Assay ◽

Group A ◽

Reaction Amplification ◽

Stool Specimens ◽

Polymerase Chain

A reverse transcription polymerase chain reaction (RT-PCR) assay is described that has been developed for the detection and serotyping of group A rotavirus in stool specimens and concentrated and non-concentrated sewage specimens.

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Extração de DNA a partir de sangue humano coagulado para aplicação nas técnicas de genotipagem de antígenos leucocitários humanos e de receptores semelhantes à imunoglobulina

Revista da Sociedade Brasileira de Medicina Tropical ◽

10.1590/s0037-86822009000600008 ◽

2009 ◽

Vol 42 (6) ◽

pp. 651-656 ◽

Cited By ~ 8

Author(s):

Daniela Maira Cardozo ◽

Gláucia Andréia Guelsin ◽

Samaia Laface Clementino ◽

Fabiano Cavalcante de Melo ◽

Marco Antônio Braga ◽

...

Keyword(s):

Polymerase Chain Reaction ◽

Killer Cell ◽

Human Leukocyte ◽

Reaction Sequence ◽

Chain Reaction ◽

Specific Sequence ◽

Salting Out ◽

Leukocyte Antigens ◽

Polymerase Chain ◽

Made In

O objetivo deste estudo foi padronizar uma metodologia de extração de DNA de alta qualidade a partir de amostras de sangue coagulado. Quarenta e oito amostras de sangue humano coagulado foram utilizadas para a extração de DNA pelo kit comercial EZ-DNA® (Biological Industries, Beit Haemek, Israel), pelo kit de coluna Neoscience® (One Lambda Inc., San Diego, CA) e pelo método modificado de salting out. Apenas o método de salting out foi capaz de extrair altas concentrações de DNA (média, 180ng/µL), as quais foram medidas pelo detector de fluorescência Qubit® (Invitrogen, USA). Este método permitiu a amplificação dos genes HLA (human leukocyte antigens) pela tecnologia PCR-SSO (polymerase chain reaction - specific sequence of oligonucleotides) Luminex, a qual exige DNA de boa qualidade, e de genes KIR (killer cell immunoglobulin-like receptors) pela técnica made in house PCR-SSP (polymerase chain reaction-sequence specific of primers), a qual demanda uma concentração específica de DNA (10ng/µL). Concluímos que a técnica de salting out modificada foi muito eficiente, simples e rápida para a extração de DNA de amostras de sangue humano coagulado, com o objetivo de realizar a genotipagem de genes HLA e KIR.

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Evaluation of Four DNA Extraction Methods for the Detection ofTritrichomonas Foetusin Feline Stool Specimens by Polymerase Chain Reaction

Journal of Veterinary Diagnostic Investigation ◽

10.1177/104063870802000518 ◽

2008 ◽

Vol 20 (5) ◽

pp. 639-641 ◽

Cited By ~ 27

Author(s):

Stephen H. Stauffer ◽

Adam J. Birkenheuer ◽

Michael G. Levy ◽

Henry Marr ◽

Jody L. Gookin

Keyword(s):

Polymerase Chain Reaction ◽

Dna Extraction ◽

Extraction Methods ◽

Chain Reaction ◽

Stool Specimens ◽

Polymerase Chain ◽

Dna Extraction Methods

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Comparison of Multiplex Gastrointestinal Pathogen Panel and Conventional Stool Testing for Evaluation of Patients With HIV Infection

Open Forum Infectious Diseases ◽

10.1093/ofid/ofz547 ◽

2020 ◽

Vol 7 (1) ◽

Author(s):

Juliana Sobczyk ◽

Sonia Jain ◽

Xiaoying Sun ◽

Maile Karris ◽

Darcy Wooten ◽

...

Keyword(s):

Polymerase Chain Reaction ◽

Retrospective Cohort ◽

Viral Infections ◽

Turnaround Time ◽

Stool Culture ◽

Chain Reaction ◽

Viral Pathogens ◽

Polymerase Chain Reaction Testing ◽

Gastrointestinal Pathogen ◽

Polymerase Chain

Abstract Background Gastrointestinal pathogen panels (GPPs) are increasingly used to identify stool pathogens, but their impact in people with HIV (PWH) is unknown. We performed a retrospective cohort study comparing GPP and conventional stool evaluation in PWH. Methods We included all PWH who underwent GPP (Biofire Diagnostics; implemented September 15, 2015) or conventional testing, including stool culture, Clostridium difficile polymerase chain reaction testing, fluorescent smears for Cryptosporidium or Giardia, and ova and parasite exams (O&P) from 2013 to 2017. A total of 1941 specimens were tested, with 169 positive specimens detected in 144 patients. We compared result turnaround time, pathogen co-infection, antibiotic treatment, and treatment outcomes between positive specimens detected by conventional testing vs GPP. Results Overall, 124 patient samples tested positive by GPP, compared with 45 patient specimens by conventional testing. The GPP group demonstrated a higher co-infection rate (48.4% vs 13.3%; P < .001) and quicker turnaround time (23.4 vs 71.4 hours; P < .001). The GPP identified 29 potential viral infections that were undetectable by conventional stool tests. Unnecessary anti-infective therapy was avoided in 9 of 11 exclusively viral infections. Exclusively nonpathogenic parasites (n = 13) were detected by conventional stool tests, the majority of which were treated with metronidazole. There were no significant differences in clinical outcomes between groups. Conclusions In PWH, GPP implementation improved antibiotic stewardship through shorter turnaround times and detection of enteric viral pathogens.

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The Changing Landscape of Pediatric Viral Enteropathogens in the Post–Rotavirus Vaccine Era

Clinical Infectious Diseases ◽

10.1093/cid/ciaa100 ◽

2020 ◽

Cited By ~ 3

Author(s):

Natasha Halasa ◽

Bhinnata Piya ◽

Laura S Stewart ◽

Herdi Rahman ◽

Daniel C Payne ◽

...

Keyword(s):

Polymerase Chain Reaction ◽

Medical Care ◽

Race And Ethnicity ◽

Quantitative Polymerase Chain Reaction ◽

Rotavirus Vaccine ◽

Older Children ◽

Chain Reaction ◽

Stool Specimens ◽

Polymerase Chain ◽

To Receive

Abstract Background Acute gastroenteritis (AGE) is a common reason for children to receive medical care. However, the viral etiology of AGE illness is not well described in the post–rotavirus vaccine era, particularly in the outpatient (OP) setting. Methods Between 2012 and 2015, children 15 days through 17 years old presenting to Vanderbilt Children’s Hospital, Nashville, Tennessee, with AGE were enrolled prospectively from the inpatient, emergency department, and OP settings, and stool specimens were collected. Healthy controls (HCs) were enrolled and frequency matched for period, age group, race, and ethnicity. Stool specimens were tested by means of reverse-transcription real-time quantitative polymerase chain reaction for norovirus, sapovirus, and astrovirus RNA and by Rotaclone enzyme immunoassay for rotavirus antigen, followed by polymerase chain reaction verification of antigen detection. Results A total of 3705 AGE case patients and 1563 HCs were enrolled, among whom 2885 case patients (78%) and 1110 HCs (71%) provided stool specimens that were tested. All 4 viruses were more frequently detected in AGE case patients than in HCs (norovirus, 22% vs 8%, respectively; rotavirus, 10% vs 1%; sapovirus, 10% vs 5%; and astrovirus, 5% vs 2%; P < .001 for each virus). In the OP setting, rates of AGE due to norovirus were higher than rate for the other 3 viruses. Children <5 years old had higher OP AGE rates than older children for all viruses. Conclusions Norovirus remains the most common virus detected in all settings, occurring nearly twice as frequently as the next most common pathogens, sapovirus and rotavirus. Combined, norovirus, sapovirus, rotavirus, and astrovirus were associated with almost half of all AGE visits and therefore are an important reason for children to receive medical care.

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