Evaluation of a novel triplex immunochromatographic test for rapid simultaneous detection of norovirus, rotavirus, and adenovirus on a single strip test.

BACKGROUND: Acute gastroenteritis is one of the major causes of morbidity and mortality in young children worldwide. Among these, rotavirus, norovirus, and adenovirus have been reported as the primary viral pathogens associated with the disease. Rapid diagnosis of viral pathogens is crucial when diarrhea outbreaks occur to ensure the timely administration of appropriate treatment and control measures. METHODS: We evaluated three immunochromatographic test kits designed for the detection of norovirus, rotavirus, and adenovirus in 71 stool specimens collected from children with diarrhea who visited clinics in Japan. The first kit is a triplex immunochromatographic test kit designed for simultaneous detections of norovirus, rotavirus, and adenovirus on a single strip (this kit was referred to as IC-A). The other two immunochromatographic test kits are a dual detection kit for rotavirus and adenovirus, and a single detection kit for norovirus (IC-B). The RT-PCR/PCR was used as the gold standard method. RESULTS: The results revealed that both IC-A and IC-B kits exhibited the same level of sensitivity of detection for rotavirus (72.7%) and adenovirus (22.7%), although the detection rate was lower than that of the RT-PCR/PCR method. However, there was a slight difference in the sensitivity of detection for norovirus between IC-A and IC-B, at 86.7% and 93.3%, respectively. The sensitivity of detection for adenovirus of both kits was relatively lower than those of RT-PCR method. This could be due to low viral load of adenovirus in clinical specimens below the detection limit of IC-A and IC-B kits. However, both immunochromatographic test kits (IC-A and IC-B) exhibited 100% specificity for norovirus, rotavirus, and adenovirus. CONCLUSIONS: The triplex immunochromatographic test kit (IC-A) designed for simultaneous detection of norovirus, rotavirus, and adenovirus has been proved to be more practical and convenient than the use of single or dual detection kits with more or less the same sensitivity and specificity of detections.

Sapovirus infection as another cause of persistent viral diarrhea: case series and review of the literature.

Human sapovirus (HuSaV) is a common cause of gastroenteritis worldwide and is responsible for approximately 4% of acute gastroenteritis episodes in Europe. As reported with norovirus, patients with immunocompromised states are at increased risk of developing HuSaV infection, which can lead to persistent diarrhea and chronic viral shedding in some individuals. Chronic infections are incompletely investigated in these patients, and, due to the lack of specific treatment for HuSaV infection, different clinical approaches were carried out in order to provide further evidence on clinical evolution of these patients with different treatments. In this retrospective study, we report five immunocompromised pediatric patients with recurrent diarrhea caused by HuSaV and long-term viral shedding. Stool samples were analyzed by real-time PCR and tested for enteropathogenic viruses and bacteria and protozoa. Among transplant recipients, reduction of immunosuppressant therapy led to clinical improvement and relief of symptoms, maintaining a balance between managing the infection and preventing graft rejection. Nitazoxanide for 14 days was only used in one of these patients, showing to be an effective therapy to achieve reduction in time to resolution of symptoms. Neither nitazoxanide nor modification of immunosuppressant therapy could avoid recurrences. Further investigations are needed to develop new approaches that can both clear the infection and avoid persistent diarrhea in these patients.

High-resolution melting analysis for simultaneous detection and discrimination between wild-type and vaccine strains of feline calicivirus.

High-resolution melting (HRM) analysis, a post-polymerase chain reaction (PCR) application in a single closed tube, is the straightforward method for simultaneous detection, genotyping, and mutation scanning, enabling more significant dynamic detection and sequencing-free turnaround time. This study aimed to establish a combined reverse-transcription quantitative PCR and HRM (RT-qPCR-HRM) assay for diagnosing and genotyping feline calicivirus (FCV). This developed method was validated with constructed FCV plasmids, clinical swab samples from living cats, fresh-frozen lung tissues from necropsied cats, and four available FCV vaccines. We performed RT-qPCR to amplify a 99-base pair sequence, targeting a segment between open reading frame (ORF) 1 and ORF2. Subsequently, the HRM assay was promptly applied using Rotor-Gene Q® Software. The results significantly revealed simultaneous detection and genetic discrimination between commercially available FCV vaccine strains, wild-type Thai FCV strains, and VS-FCV strains within a single PCR reaction. There was no cross-reactivity with other feline common viruses, including feline herpesvirus-1, feline coronavirus, feline leukemia virus, feline immunodeficiency virus, and feline morbillivirus. The detection limit of the assay was 6.18 × 101 copies/µl. This study, therefore, is the first demonstration of the uses and benefits of the RT-qPCR-HRM assay for FCV detection and strain differentiation in naturally infected cats.

An approach to zwitterionic peptide design for colorimetric detection of the Southampton norovirus SV3CP protease.

Noroviruses are highly contagious and are one of the leading causes of acute gastroenteritis worldwide. Due to a lack of effective antiviral therapies, there is a need to diagnose and surveil norovirus infections to implement quarantine protocols and prevent large outbreaks. Currently, the gold standard of diagnosis uses reverse transcription polymerase chain reaction (RT-PCR), but PCR can have limited availability. Here, we propose a combination of a tunable peptide substrate and gold nanoparticles (AuNPs) to colorimetrically detect the Southampton norovirus 3C-like protease (SV3CP), a key protease in viral replication. Careful design of the substrate employs a zwitterionic peptide with opposite charged moieties on the C- and N- termini to induce a rapid color change visible to the naked eye; thus, this color change is indicative of SV3CP activity. This work expands on existing zwitterionic peptide strategies for protease detection by systematically evaluating the effects of lysine and arginine on nanoparticle charge screening. We also determine a limit of detection for SV3CP of 28.0 nM with comparable results in external breath condensate, urine, and fecal matter for 100 nM of SV3CP. The key advantage of this system is its simplicity and accessibility, thus making it an attractive tool for qualitative point-of-care diagnostics.

Point-of-Care Testing for Norovirus Typing Using CRISPR/Cas12a Combined with Reverse Transcription Recombinase Polymerase Amplification.

Noroviruses (NoVs) are one of the leading causes of acute gastroenteritis in humans. This study combined reverse transcription recombinase polymerase amplification (RT-RPA) with a clustered regularly interspaced short palindromic repeat/CRISPR-associated protein (CRISPR/Cas) nucleic acid detection system to develop a point-of-care testing (POCT) technology for typing NoVs. The detection can be completed within 35 min at 37 °C, covering each genotype of genogroup I (GI) and II (GII) NoVs. The sensitivity of this method is 10 copies/µL for GI and 1 copy/µL for GII NoV plasmids. For the detection of clinical samples, the detection results of this method for NoV infected samples are consistent with the RT-qPCR detection method in the laboratory, and this detection method has no cross-reactivity with rotavirus and adenovirus. Therefore, the detection method established in this study enables the diagnosis and screening of suspected patients and close contacts by POCT, which is important for the timely identification and control of NoV outbreaks. In addition, the typing detection of GI and GII NoVs can achieve a precise diagnosis and treatment of patients infected with NoVs.

Multi-event capture-recapture models estimate the diagnostic performance of serological tests for myxoma and rabbit haemorrhagic disease viruses in the absence of reference samples.

Estimation of the diagnostic performance of serological tests often relies on another test assumed as a reference or on samples of known infection status, yet both are seldom available for emerging pathogens in wildlife. Longitudinal disease serological data can be analysed through multi-event capture-mark-recapture (MECMR) models accounting for the uncertainty in state assignment, allowing us to estimate epidemiological parameters such as incidence and mortality. We hypothesized that by estimating the uncertainty in state assignment, MECMR models estimate the diagnostic performance of serological tests for rabbit haemorrhagic disease virus (RHDV) and myxoma virus (MYXV). We evaluated this hypothesis on longitudinal serological data of three tests of RHDV and one test of MYXV in two populations of the European rabbit (Oryctolagus cuniculus algirus). First, we selected the optimal cut-off threshold for each test using finite mixture models, a reference method not relying on reference tests or samples. Second, we used MECMR models to compare the diagnostic sensitivity (Se) and specificity (Sp) of the three tests for RHDV. Third, we compared the estimates of diagnostic performance by MECMR and finite mixture models across a range of cut-off values. The MECMR models showed that the RHDV test employing GI.2 antigens (Se: 100%) outperformed two tests employing GI.1 antigens (Se: 21.7% ± 8.6% and 8.7% ± 5.9%). At their selected cut-offs (2.0 for RHDV GI.2 and 2.4 for MYXV), the estimates of Se and Sp were concordant between the MECMR and finite mixture models. Over the duration of the study (May 2018 to September 2020), the monthly survival of European rabbits seropositive for MYXV was significantly higher than that of seronegative rabbits (82.7% ± 4.9% versus 61.5% ± 12.7%) at the non-fenced site. We conclude that MECMR models can reliably estimate the diagnostic performance of serological tests for RHDV and MYXV in European rabbits. This conclusion could extend to other diagnostic tests and host-pathogen systems. Longitudinal disease surveillance data analysed through MECMR models allow the validation of diagnostic tests for emerging pathogens in novel host species while simultaneously estimating epidemiological parameters.

[Determining the Prevalence of Norovirus Infection in Diarrheal Patients and Evaluation of Different Diagnostic Methods]. / Ishalli Hastalarda Norovirüs Sikliginin ve Farkli Tani Yöntemlerinin Duyarliliklarinin Belirlenmesi.

Norovirus is one of the viruses that cause gastroenteritis in humans, characterized by symptoms of vomiting and diarrhea. The prevalence of norovirus, known as the leading cause of epidemic gastroenteritis, is remarkable in sporadic cases. Easy-to-apply diagnostic methods based on antigen detection such as enzyme immunoassay (EIA) and immunochromatography (ICG) used to diagnose norovirus infections generally have high specificity rates but lower sensitivity rates that can change according to the conditions. In this study it was aimed to determine the prevalence of norovirus and other gastroenteritis causative viruses in diarrheal patients and determine the sensitivity and specificity rates of EIA and ICG methods in sporadic cases by the chosen gold standard molecular reference method real-time reverse transcriptase polymerase chain reaction (rRT-PCR). In this study, 184 stool samples that met the study criteria and sent to Istanbul University Istanbul Faculty of Medicine Medical Microbiology Laboratory for routine bacteriological culture between January-July 2018 were included. All samples were evaluated with diagnostic kits BD MAX Enteric Viral Panel (Becton Dickinson, Canada) for rRT-PCR, RIDASCREEN Norovirus 3rd Generation (C1401) (R-Biopharm, Germany) for EIA, RIDAQUICK Norovirus Test (N1402) (R-Biopharm, Germany) for ICG, according to the manufacturer instructions. In terms of the presence of norovirus in 184 stool samples, 7 (3.8%) positive results were obtained by EIA method, 8 (4.3%) by ICG method, and 14 (7.6%) by rRT-PCR method. By accepting the rRT-PCR as a reference method, the sensitivity and specificity of the EIA method were determined as 50% and 100% and of the ICG method as 57% and 100%, respectively. The numbers and percentages of positivity for rotavirus, sapovirus, astrovirus and adenovirus, including coinfections were 30 (16.3%), 5 (2.7%), 2 (1%), 1 (0.5%), respectively. In this study, it was determined that norovirus, alone or together with other viral agents is frequently detected in patients with diarrhea and there was no difference in the frequency between age groups and genders. This causative agent which is not routinely investigated in our country should be considered when evaluating patients with diarrhea and/or vomiting. It seems that EIA and ICG methods are easy to apply, have high specificity but have limited sensitivity in sporadic cases in the diagnosis of norovirus. It is thought that the detection of the true frequency of norovirus and high sensitivity rates can only be achieved by preferring rRT-PCR in the diagnosis. It would be useful for the laboratories to choose the method to be used in the diagnosis of norovirus according to the characteristics of the cases and diagnostic methods.

Epidemiological and Genetic Characterization of Sapovirus in Patients with Acute Gastroenteritis in Valencia (Spain).

Sapovirus is a common cause of acute gastroenteritis in all age groups. Sapovirus infections are seldom investigated in Spain, and its epidemiology in the country is not well known. The use of molecular diagnostic procedures has allowed a more frequent detection of sapoviruses in patients with diarrhea. A total of 2545 stool samples from patients with acute gastroenteritis attended from June 2018 to February 2020 at the Clinic University Hospital in Valencia, Spain, were analyzed by reverse transcription (RT) and real-time multiplex PCR (RT-PCR) to investigate the etiology of enteric infections. Sapovirus was the second enteric virus detected with a positive rate of 8%, behind norovirus (12.2%) and ahead of rotavirus (7.1%), astrovirus (4.9%) and enteric adenoviruses (2.9%). Most sapovirus infections occurred in infants and young children under 3 years of age (74%) with the highest prevalence in autumn and early winter. Coinfections were found in 25% of the patients with sapovirus diarrhea, mainly with other enteric viruses. Genotyping demonstrated the circulation of seven different genotypes during the study period, with a predominance of genotypes GI.1, GI.2, and GII.1. Phylogenetic analysis showed that genogroup GII strains form a cluster separated from genogroup GI and GV, being genotype GV.1 strains related to genotype GI.1 and GI.2 strains.

Investigation of Feline calicivirus infection in cats with upper respiratory tract disease in Diyarbakir, Turkey / Investigação de infecção por calicivírus felino em gatos com doença do trato respiratório superior na região de Diyarbakir, Turquia

Feline calicivirus is among the most common pathogenic microorganisms in upper respiratory tract disease (URTD) and oral lesions of cats. It leads to stomatitis, oral ulceration, ocular and nasal discharge, conjunctivitis, fever, lameness, anorexia, hypersalivation, pneumonia, respiratory distress, coughing, and depression in infected cats. This study aimed to determine the role of Feline calicivirus (FCV) in cats with the upper respiratory tract disease in the Diyarbakir region, Turkey, to provide treatment for infected cats and contribute to the disease prophylaxis. The study material consisted of 10 cats (control group) considered to be healthy according to the clinical examination and 20 cats with URTD that were not vaccinated against Feline calicivirus infection of different breeds, ages, and genders brought to Dicle University Veterinary Faculty Prof. Dr. Servet SEKIN Polyclinic with URTD. After routine clinical examinations of the animals, oral and conjunctival swabs and blood samples were taken. Hematological and biochemical analyzes of blood samples were performed. Swab samples were analyzed by the polymerase chain reaction (PCR) method for the diagnosis of the agent. Oral lesions, hypersalivation, ocular and nasal discharge, coughing, and breathing difficulties were seen in clinical examinations of cats with URTD. Feline calicivirus was detected in only one cat's conjunctival swab sample in PCR analyses. As a result, we found that Feline calicivirus infection was present in cats with URTD in the Diyarbakir region, and 5% positivity was found in cats with clinical symptoms according to PCR analysis.(AU)

O calicivírus felino está entre os microrganismos patogênicos mais comuns nas doenças do trato respiratório superior de gatos, determinando estomatites, ulcerações orais, descarga ocular e nasal, conjuntivite, febre, manqueira, anorexia, hipersalivação, pneumonia, distúrbios respiratórios, tosse e depressão. O presente trabalho foi delineado para determinar o papel do calicivírus felino (CVF) em gatos com doenças do trato respiratório superior na região de Diyarbakir, Turquia. Com o objetivo de orientar a prescrição do tratamento para os gatos infectados e contribuir com a profilaxia da doença. O material de estudo consistiu em 10 gatos saudáveis sem qualquer problema de saúde e 20 gatos acometidos por doenças do trato respiratório superior que não haviam sido vacinados contra a infecção pelo calicivírus felino. Os animais de diferentes raças, idades e gêneros foram encaminhados para a Universidade de Dicle, na Faculdade de Veterinária, na policlínica Professor Dr. Servet Sekin. Após o exame clínico de rotina dos animais, foram colhidos swabs orais e da conjuntiva e amostras de sangue. Análises hematológicas e bioquímicas das amostras de sangue foram realizadas e os swabs foram analisados pelo método da reação em cadeia pela polimerase (PCR) para diagnóstico do agente. Nos gatos infectados foram constatadas: lesões orais, hipersalivação, descargas oculares e nasais, tosse e dificuldade respiratória. O calicivírus felino foi detectado pela técnica de PCR no swab conjuntival de apenas um gato. A conclusão obtida foi que a infecção pelo calicivírus felino foi detectada pela técnica de PCR na região de Diyarbakir, Turquia, em gatos com doença do trato respiratório superior com a frequência de 5%.(AU)

Polymerase chain reaction primer sets for the detection of genetically diverse human sapoviruses.

Sapoviruses are increasingly being recognized as pathogens associated with gastroenteritis in humans. Human sapoviruses are currently assigned to 18 genotypes (GI.1-7, GII.1-8, GIV.1, and GV.1-2) based on the sequence of the region encoding the major structural protein. In this study, we evaluated 11 polymerase chain reaction (PCR) assays using published and newly designed/modified primers and showed that four PCR assays with different primer combinations amplified all of the tested human sapovirus genotypes using either synthetic DNA or cDNA prepared from human sapovirus-positive fecal specimens. These assays can be used as improved broadly reactive screening tests or as tools for molecular characterization of human sapoviruses.

Viral gastroenteritis in hospitalized patients: Evaluation of immunochromatographic methods for rapid detection in stool samples.

BACKGROUND: . Viral infections are recognized as the most common cause of acute gastroenteritis (AGE). Virus detection by immune analytical methods is recommended for diagnosis because of its simplicity and low cost. OBJECTIVES: . Two commercial immunochromatographic (ICG) techniques (Materlab) for rapid detection of rotavirus/adenovirus and norovirus respectively, were evaluated by comparison to the results obtained using PCR methods. In addition, clinical and epidemiologic characteristics of AGE infections have been described. STUDY DESIGN: . A total of 100 faecal samples collected from patients with AGE (84% children) admitted into a Spanish Hospital between February and July 2018, were studied for rotavirus-A, adenovirus and norovirus GI/GII by the ICG tests as well as by PCR and sequencing. Other enteric viruses (enterovirus and astrovirus) were investigated by PCR methods. Gastrointestinal bacteria and parasites were also tested. RESULTS: . Evaluated ICG tests yielded high specificity (>97%). Sensitivity values were high for rotavirus/adenovirus (>80%) but lower for norovirus (57%). Overall, and taking into account coinfections, viruses (32%), bacteria (14%) and parasites (1%) could be detected. Rotavirus-A were the most frequently identified viruses (16%), followed by enterovirus (12%), norovirus (4%), adenovirus 41 (4%) and astrovirus (1%). In five vaccinated children, a rotavirus was detected. CONCLUSIONS: . ICG technique is a useful tool for the routine diagnosis of AGE infections at hospital, but for surveillance and epidemiological studies, it is needed the use of amplification and sequencing methods, which also allow monitoring of new strains or variants emergence. In this study, an etiological pathogen was determined only in 44% of samples.

A service evaluation of simultaneous near-patient testing for influenza, respiratory syncytial virus, Clostridium difficile and norovirus in a UK district general hospital.

BACKGROUND: The Cepheid® GeneXpert® (GXP) can simultaneously test for norovirus (NV), Clostridium difficile (CD), influenza A/B (IFA/B) and respiratory syncytial virus (RSV). AIM: To compare centralized multiplex polymerase chain reaction (PCR) testing with localized GXP testing at a district general hospital. METHODS: From December 2017 to December 2018, samples received at Whipps Cross University Hospital (WCUH) were first tested at the local laboratory before transport centrally to the Royal London Hospital (RLH). At the RLH, a non-proprietary multiplex reverse transcriptase (RT) PCR assay was performed, which also tested for gastrointestinal or respiratory pathogens not tested for by the GXP. FINDINGS: A total of 1111 stool and respiratory samples were processed at both sites; 591 were respiratory and 520 were stool samples. Compared to centralized testing, the GXP gave sensitivity, specificity, and NPV all in excess of 97%, with the exception of RSV. The RSV assay had a sensitivity of 66.7% (95% confidence interval (CI) 24.1, 94.0) but an NPV of 99.7% (95% CI 98.6, 99.9). At the RLH, 65 (5.9%) additional respiratory or gastrointestinal viruses were detected, predominantly rhinovirus 35 (3.2%) and adenovirus 11 (1.0%). Compared to centralized testing, the median time saved for local respiratory and gastrointestinal sample testing was 19 h and 46 min and 17 h and 6 min, respectively. CONCLUSIONS: Local GXP testing compared to centralized multiplex PCR testing for IF, NV and CD, demonstrated sensitivities, specificities and NPV between 95% and 100%. Turnaround times were faster, enabling quicker infection prevention and control decision making. In our local setting (WCUH), the GXP demonstrated the potential to reduce NV and IFA/B outbreaks.

Gastroenteritis aguda por norovirus en pacientes con atención hospitalaria: estudio transversal / Acute gastroenteritis due to norovirus in patients with hospital care: a cross-sectional study

Resumen Introducción: Debido a la disponibilidad de técnicas moleculares en la atención clínica, las gastroenteritis agudas (GEA) por norovirus han retomado importancia como un agente causante de hospitalización. El objetivo de este estudio fue describir las características clínicas y evolutivas de pacientes menores de 16 años hospitalizados por GEA por norovirus. Métodos: Estudio retrospectivo. Se recabó información clínica de los pacientes atendidos en hospitalización del 1 de noviembre del 2016 al 28 de febrero del 2018 por GEA con detección de norovirus (genotipo I y II) en heces por medio de reacción en cadena de la polimerasa con transcriptasa inversa. Resultados: Estudiamos 103 pacientes; 96 (93.2%; intervalo de confianza del 95% [IC 95%]: 86.6-96.7%) con deteccion de genotipo II y 7 (6.8%; IC 95%: 5.3-8.7%) de genotipo I; 76 (73.8%) ≤5 anos. El 48.5% fueron atendidos durante el invierno. La evolucion fue a la autolimitacion en menos de 7 días en todos con manejo hidroelectrolitico. No hubo diferencias en la gravedad y sintomas segun el grupo viral: en ambos predominaron los vómitos (82%). Solo un paciente cursó con perforación intestinal por coinfección con Shigella sp.; tres pacientes (3.1%) manifestaron crisis convulsivas (dos febriles y una epiléptica). Conclusiones: La GEA por norovirus, a pesar de causar una enfermedad meritoria de hospitalización, tiene un pronóstico favorable con autolimitación rápida. Su detección por pruebas rápidas en heces podría evitar la prescripción injustificada de antibióticos.

Abstract Background: Because of the availability of molecular techniques in clinical care, acute gastroenteritis (AGE) due to norovirus has returned to importance as a causative agent of hospitalization. The aim of this study was to describe the clinical features and evolution of patients less than 16 years hospitalized for AGE associated with norovirus. Methods: Retrospective study. Clinical information of the patients attended from November 1, 2016 to February 28, 2018 by AGE with detection of norovirus (genotype I and II) in faeces by means of polymerase chain reaction with reverse transcriptase was collected. Results: We studied 103 patients; 96 (93.2%; 95% confidence interval [95% CI]: 86.6-96.7%) with genotype II detection and seven (6.8%; 95% CI: 5.3-8.7%) genotype I; 76 (73.8%) ≤5 years. 48.5% attended during the winter. The evolution was to self-limitation in less than 7 days in all with hydro electrolytic management. There were no differences in the severity and symptoms according to the viral group; in both cases the vomiting predominated (82%). Only one patient had intestinal perforation due to co-infection with Shigella sp.; three patients (3.1%) manifested seizures (two febrile and one epileptic convulsions). Conclusions: Despite causing a meritorious disease of hospitalization, GEA by norovirus has a favorable prognosis with rapid self-limitation. Its timely detection by rapid tests in feces could avoid the unjustified prescription of antibiotics.

Investigation of Norovirus genogroups (GI, GII and GIV) in stool of pet dogs with diarrhea / Investigação de genogrupos de norovírus (GI, GII e GIV) nas fezes de cães de estimação com diarréia

In this study, we searched the existence of human norovirus (NoV) GI, GII and GIV in the stool of 128 pet dogs with diarrhea, of different sex, age and breed, in Burdur, Turkey, using Real-Time PCR method. Human NoV GII was found in only 5 of the 128 dog stool samples (3.91%). It was discovered that human NoV existed most in crossbreed, female and aged 24 months or over dogs. These dogs found with human NoV GII were either bought from pet shops, stray dogs or taken as puppy of another pet dog. The sheltering conditions of these dogs were moderate and they were fed with home food residue and dry food. It was also found that most of them were vaccinated and had certain walking sites. The owners of the animals detected with infection generally did not have the habit of washing their hands or changing their clothes before or after caring their pets. We strongly advice that dog owners' personal hygiene, the necessity of changing their clothes during their contact with animals, the environment provided for the dog, the sensitivity in caring, use of strong and effective disinfectant, keeping the dogs away from toilets and sewerage systems, as well as not feeding them with food residues are crucial issues in dogs' care. Owners of the dogs with NoV GII were middle aged or elderly people, male, and there were no children in their houses. As these dogs are treated like the owner's child, it is assumed that they could be transmitted with NoV GII as a result of close interaction with their owner.(AU)

Neste estudo pesquisamos a existência de norovírus humano (NoV) GI, GII e GIV nas fezes de 128 cães com diarréia, de diferentes sexos, idades e raças, em Burdur, Turquia, utilizando o método de PCR em tempo real. NoV GII humano foi encontrado em apenas 5 das 128 amostras de fezes de cães (3,91%). Foi descoberta NoV humana, principalmente em cruzamentos, fêmeas e cães com idade igual ou superior a 24 meses. Os cães encontrados com NoV GII humano foram comprados de lojas de animais, eram vira-latas ou foram tomados como filhotes de outro cão de estimação. As condições de abrigo desses cães eram moderadas. Os cães foram alimentados com restos de comida caseira e comida seca. Verificou-se também que a maioria dos animais foi vacinada e tinham locais adequados para caminhada. Os donos dos animais detectados com infecção geralmente não tinham o hábito de lavar as mãos ou trocar de roupa antes ou depois de cuidar de seus animais de estimação. Aconselhamos que a higiene pessoal dos donos, a necessidade de trocar de roupa durante o contato com animais, o ambiente fornecido para o cão, a sensibilidade no cuidado, o uso de desinfetantes eficazes, manter os cães longe de banheiros e esgotos, assim como evitar alimentá-los com resíduos alimentares, são questões cruciais no cuidado dos cães. Os proprietários dos cães com NoV GII são de meia-idade ou idosos, a maioria do sexo masculino, e não havia crianças em suas casas. Como esses cães são tratados como um filho, presume-se que eles foram infectados com o NoV GII como resultado de uma interação próxima com o proprietário.(AU)

Broadly reactive real-time reverse transcription-polymerase chain reaction assay for the detection of human sapovirus genotypes.

Sapoviruses are associated with acute gastroenteritis. Human sapoviruses are classified into four distinct genogroups (GI, GII, GIV, and GV) based on their capsid gene sequences. A TaqMan probe-based real-time reverse transcription-polymerase chain reaction (RT-PCR) assay that detects the representative strains of these four genogroups is widely used for screening fecal specimens, shellfish, and environmental water samples. However, since the development of this test, more genetically diverse sapovirus strains have been reported, which are not detectable by the previously established assays. In this study, we report the development of a broader-range sapovirus real-time RT-PCR assay. The assay can detect 2.5 × 107 and 2.5 × 10 1 copies of sapovirus and therefore is as sensitive as the previous test. Analysis using clinical stool specimens or synthetic DNA revealed that the new system detected strains representative of all the 18 human sapovirus genotypes: GI.1-7, GII.1-8, GIV.1, and GV.1, 2. No cross-reactivity was observed against other representative common enteric viruses (norovirus, rotavirus, astrovirus, and adenovirus). This new assay will be useful as an improved, broadly reactive, and specific screening tool for human sapoviruses.

Comparison of Multiplex Gastrointestinal Pathogen Panel and Conventional Stool Testing for Evaluation of Diarrhea in Patients with Inflammatory Bowel Diseases.

BACKGROUND AND AIMS: Gastrointestinal pathogen panels (GPPs) are increasingly being used for evaluation of diarrhea. The impact of these tests on patients with inflammatory bowel diseases (IBD) is unknown. We performed a time-interrupted cohort study comparing GPPs and conventional stool evaluation in patients with IBD with diarrhea. METHODS: We included 268 consecutive patients with IBD who underwent GPP (BioFire Diagnostics®) (n = 134) or conventional stool culture and Clostridium difficile polymerase chain reaction testing (n = 134) during suspected IBD flare between 2012 and 2016. Primary outcome was composite of 30-day IBD-related hospitalization, surgery, or emergency department visit; secondary outcome was IBD treatment modification. RESULTS: Overall, 41/134 (30.6%) patients tested positive on GPP (18 C. difficile, 17 other bacterial infections, and 6 viral pathogens) versus 14/134 patients (10.4%, all C. difficile) testing positive on conventional testing. Rate of IBD treatment modification in response to stool testing was lower in GPP group as compared conventional stool testing group (35.1 vs. 64.2%, p < 0.01). On multivariate analysis, diagnostic evaluation with GPP was associated with three times higher odds of IBD-related hospitalization/surgery/ED visit (95% CI, 1.27-7.14), as compared to conventional stool testing. This negative impact was partly mediated by differences in ordering provider specialty, with non-gastroenterologists more likely to order GPP as compared to gastroenterologists. CONCLUSIONS: In patients with suspected flare of IBD, GPPs have higher pathogen detection rate and lead to lower rate of IBD treatment modification. A diagnostic testing strategy based on GPPs is associated with higher hospital-related healthcare utilization as compared to conventional stool testing, particularly when utilized by non-gastroenterologists.

Norovírus no município de São Paulo, 2010-2016: estudo transversal sobre a principal causa de gastroenterite infantil / Norovirus en el Municipio de São Paulo, Brasil, 2010-2016: estudio transversal sobre la principal causa de gastroenteritis infantil / Norovirus in São Paulo city, Brazil, 2010-2016: a cross-sectional study of the leading cause of gastroenteritis in children

Objetivo: descrever casos de doença diarreica aguda por norovírus em crianças menores de 5 anos do município de São Paulo, Brasil. Métodos: estudo transversal com dados provenientes da Vigilância Epidemiológica das Gastroenterites Causadas por Rotavírus; foi definido como caso o paciente internado em unidade sentinela por doença diarreica aguda e identificação laboratorial do norovírus como agente etiológico, entre os anos de 2010 e 2016. Resultados: durante o período estudado, a proporção de casos de norovírus em menores de 5 anos de idade ultrapassou a proporção de casos de rotavírus, agente considerado predominante na infância; o norovírus foi associado a 28,4% do total de casos notificados, ocorrendo o ano todo, principalmente nos meses mais quentes. Conclusão: norovírus foi o principal agente etiológico identificado em crianças menores de 5 anos com doença diarreica aguda no município de São Paulo.

Objetivo: describir casos de enfermedad diarreica aguda por Norovirus en niños menores de 5 años provenientes del Municipio de São Paulo, Brasil. Métodos: Estudio transversal con datos de la Vigilancia Epidemiológica de las Gastroenteritis causadas por Rotavirus. Se definió como caso el paciente internado en unidad centinela por enfermedad diarreica aguda e identificación de laboratorio del Norovirus como agente etiológico entre los años de 2010 y 2016. Resultados: Durante el período estudiado, la proporción de casos de Norovirus en menores de 5 años superó la proporción de casos de Rotavirus, agente considerado predominante en la infancia. El Norovirus fue asociado al 28,4% del total de los casos notificados, ocurriendo todo el año, principalmente en los meses más cálidos. Conclusión: el Norovirus fue el principal agente etiológico identificado en niños menores de 5 años con enfermedad diarreica aguda en el Municipio de São Paulo.

Objective: to describe cases of acute diarrheal disease caused by norovirus in children under 5 years old in São Paulo city, Brazil. Methods: this was a cross-sectional study using data from Epidemiological Surveillance of Gastroenteritis due to Rotavirus; cases were defined as patients hospitalized in a sentinel unit because of acute diarrheal disease and laboratory identification of norovirus as the etiological agent between 2010 and 2016. Results: during the study period, the proportion of norovirus cases in children under 5 years old exceeded the proportion of Rotavirus, an agent considered predominant in childhood; norovirus was associated with 28.4% of total reported cases, occurring all year round, especially in warmer months. Conclusion: norovirus was the leading etiological agent identified in children under 5 years old with acute diarrheal disease in São Paulo city.

Single-step detection of norovirus tuning localized surface plasmon resonance-induced optical signal between gold nanoparticles and quantum dots.

A new method of label free sensing approach with superior selectivity and sensitivity towards virlabel-freeon is presented here, employing the localized surface plasmon resonance (LSPR) behavior of gold nanoparticles (AuNPs) and fluorescent CdSeTeS quantum dots (QDs). Inorganic quaternary alloyed CdSeTeS QDs were capped with L-cysteine via a ligand exchange reaction. Alternatively, citrate stabilized AuNPs were functionalized with 11-mercaptoundecanoic acid to generate carboxylic group on the gold surface. The carboxylic group on the AuNPs was subjected to bind covalently with the amine group of L-cysteine capped CdSeTeS QDs to form CdSeTeS QDs/AuNPs nanocomposites. The fluorescence of CdSeTeS QDs/AuNPs nanocomposite shows quenched spectrum of CdSeTeS QDs at 640 nm due to the close interaction with AuNPs. However, after successive addition of norovirus-like particles (NoV-LPs), steric hindrance-induced LSPR signal from the adjacent AuNPs triggered the fluorescence enhancement of QDs in proportion to the concentration of the target NoV-LPs. A linear range of 10-14 to 10-9 g mL-1 NoV-LPs with a detection limit of 12.1 × 10-15 g mL-1 was obtained. This method was further applied on clinically isolated norovirus detection, in the range of 102-105 copies mL-1 with a detection limit of 95.0 copies mL-1, which is 100-fold higher than commercial ELISA kit. The superiority of the proposed sensor over other conventional sensors is found in its ultrasensitive detectability at low virus concentration even in clinically isolated samples. This proposed detection method can pave an avenue for the development of high performance and robust sensing probes for detection of virus in biomedical applications.

Investigation of a food-borne outbreak of gastroenteritis in a school canteen revealed a variant of sapovirus genogroup V not detected by standard PCR, Sollentuna, Sweden, 2016.

A food-borne outbreak of gastroenteritis with more than 650 suspected cases occurred in April 2016 in Sollentuna, Sweden. It originated in a school kitchen serving a total of 2,700 meals daily. Initial microbiological testing (for Campylobacter, Salmonella, Shigella, Yersinia, Giardia, Cryptosporidium, Entamoeba histolytica, adeno-, astro-, noro-, rota- and sapovirus) of stool samples from 15 symptomatic cases was negative, despite a clinical presentation suggestive of calicivirus. Analyses of the findings from both the Sollentuna municipality environmental team and a web-based questionnaire suggested that the source of the outbreak was the salad buffet served on 20 April, although no specific food item could be identified. Subsequent electron microscopic examination of stool samples followed by whole genome sequencing revealed a variant of sapovirus genogroup V. The virus was not detected using standard PCR screening. This paper describes the epidemiological outbreak investigation and findings leading to the discovery.