Association between detection rate of norovirus GII and climatic factors in the Northwest Amazon region.

Worldwide, approximately one fifth of all cases of diarrhea are associated with norovirus, mainly in children, with a defined seasonality in temperate climates, but seasonal dynamics are less known in tropical climates. The objective was to investigate the impact of external clinical, epidemiological, and climatic factors on norovirus detection rates in samples from children under 5 years of age from Roraima, the Amazon region of Brazil. A total of 941 samples were included. According to climatic factors, we observed correlations between external climatic factors and weekly positivity rates, where temperature (P = 0.002), relative humidity (P = 0.0005), absolute humidity (P < 0.0001) and wind speed had the strongest effect (P = 0.0006). The Brazilian Amazon region presents a typical and favorable scenario for the persistence, expansion, and distribution of viral gastroenteritis. Importance: This study is important as it will serve as a basis for studies carried out in Brazil and Latin American countries on the epidemiological importance, seasonality, climate change, antigenic diversity, among other factors in the circulation of gastroenteric virus.

Factors associated with antibiotic use in children hospitalized for acute viral gastroenteritis and the relation to rotavirus vaccination.

Evidence on unnecessary antibiotic use in children with acute viral gastroenteritis (AGE) is scarce. We characterized the extent and correlates of antibiotic use among children hospitalized with viral AGE. A single-center study enrolled children aged 0-59 months hospitalized for AGE between 2008 and 2015 in Israel. Information was collected on laboratory tests, diagnoses, antibiotic treatment, and rotavirus vaccination. Stool samples were tested for rotavirus antigen, GII-norovirus, and stool cultures were performed for bacterial enteropathogens. Data from 2240 children were analyzed. Rotavirus vaccine was given to 79% of eligible children. Rotavirus test was performed on 1419 (63.3%) children. Before the introduction of universal rotavirus vaccination (2008-2010), rotavirus positivity in stool samples was 37.0%, which declined to 17.3% during the universal vaccination years (2011-2015). Overall, 1395 participants had viral AGE. Of those, 253 (18.1% [95% CI 16.1-20.2]) had unnecessary antibiotic treatment, mostly penicillin 46.6%, ceftriaxone 34.0% and azithromycin 21.7%. A multivariable analysis showed an inverse association between rotavirus vaccination and unnecessary antibiotic treatment (odds ratio = 0.53 [95% CI 0.31-0.91]), while positive associations were found with performing chest-X-ray test (3.00 [1.73-5.23]), blood (3.29 [95% CI 1.85-5.86]) and urine cultures (7.12 [3.77-13.43]), levels of C-reactive protein (1.02 [1.01-1.02]) and leukocytes (1.05 [1.01-1.09]). The results were consistent in an analysis of children with laboratory-confirmed rotavirus or norovirus AGE, or after excluding children with CRP > 50 mg/L. In conclusion, antibiotic prescription was common among hospitalized children with viral AGE, which was inversely related to rotavirus vaccination, possibly due to less severe illness in the vaccinated children.

Changes in norovirus incidence in Victoria, Australia, 2022: are we back to normal yet after COVID?

Abstract: There were 108 norovirus-positive outbreaks in 2022, with 45 (41.7%) occurring during the first quarter (Q1), January-March. Aged care facilities accounted for 44.4% of norovirus-positive outbreaks; 43.5% were in childcare settings. Overall, the GII.P31/GII.4 genotype was the most common, involved in 39.4% of outbreaks; however, there were shifts in the most common genotype across the year. In Q1, the GII.P31/GII.4 genotype accounted for 73.3% of typed outbreaks, but by Q3 (July-September) the GII.P7/GII.6 was the most prominent genotype at 45.0%. In Q4 (October-December), the dominant genotype had changed again to GII.P16/GII.4 (52.6%). While the incidence of norovirus outbreaks in 2022 was average regarding overall prevalence and genotype diversity, there are still ongoing effects from the coronavirus disease 2019 (COVID-19) pandemic in relation to seasonality, outbreak demographics and specimen referral.

Epidemiological Characteristics and Genotypic Features of Rotavirus and Norovirus in Jining City, 2021-2022.

Diarrhea, often caused by viruses like rotavirus (RV) and norovirus (NV), is a global health concern. This study focuses on RV and NV in Jining City from 2021 to 2022. Between 2021 and 2022, a total of 1052 diarrhea samples were collected. Real-Time Quantitative Fluorescent Reverse Transcriptase-PCR was used to detect RV-A, NV GI, and NV GII. For RV-A-positive samples, VP7 and VP4 genes were sequenced for genotype analysis, followed by the construction of evolutionary trees. Likewise, for NV-GII-positive samples, VP1 and RdRp genes were sequenced for genotypic analysis, and evolutionary trees were subsequently constructed. Between 2021 and 2022, Jining City showed varying detection ratios: RV-A alone (excluding co-infection of RV-A and NV GII) at 7.03%, NV GI at 0.10%, NV GII alone (excluding co-infection of RV-A and NV GII) at 5.42%, and co-infection of RV-A and NV GII at 1.14%. The highest RV-A ratios were shown in children ≤1 year and 2-5 years. Jining, Jinxiang County, and Liangshan County had notably high RV-A ratios at 24.37% (excluding co-infection of RV-A and NV GII) and 18.33% (excluding co-infection of RV-A and NV GII), respectively. Jining, Qufu, and Weishan had no RV-A positives. Weishan showed the highest NV GII ratios at 35.48% (excluding co-infection of RV-A and NV GII). Genotype analysis showed that, in 2021, G9P[8] and G2P[4] were dominant at 94.44% and 5.56%, respectively. In 2022, G8P[8], G9P[8], and G1P[8] were prominent at 75.86%, 13.79%, and 10.35%, respectively. In 2021, GII.3[P12], GII.4[P16], and GII.4[P31] constituted 71.42%, 14.29%, and 14.29%, respectively. In 2022, GII.3[P12] and GII.4[P16] accounted for 55.00% and 45.00%, respectively. RV-A and NV showed varying patterns for different time frames, age groups, and regions within Jining. Genotypic shifts were also observed in prevalent RV-A and NV GII strains in Jining City from 2021 to 2022. Ongoing monitoring of RV-A and NV is recommended for effective prevention and control.

Navigating Viral Gastroenteritis: Epidemiological Trends, Pathogen Analysis, and Histopathological Findings.

BACKGROUND: Gastroenteritis is a common cause of morbidity and mortality globally. Its cause encompasses a spectrum of agents, including viruses, bacteria, parasites, toxins, and drugs. Viruses account for a considerable portion of gastroenteritis cases across all age groups, typically presenting with symptoms like nausea, vomiting, diarrhea, dehydration, anorexia, and weight loss. While sporadic cases occur, viral gastroenteritis is more frequently observed in outbreaks within closely knit communities such as daycare facilities, nursing homes, and cruise ships. Therefore, it becomes necessary to determine when healthcare providers should consider this condition in their differential diagnosis and to develop the most effective strategy to confirm the diagnosis. METHODS: De-identified data of patients with gastroenteritis were collected over a five-year period utilizing the Patient Cohort Explorer, an electronic health record at the University of Mississippi Medical Center. Confirmatory laboratory tests employed the BioFire® FilmArray® multiplex polymerase chain reaction for gastrointestinal pathogens. Out of the 22 most common agents associated with gastroenteritis, only viral pathogens, specifically adenovirus, astrovirus, norovirus, rotavirus, and sapovirus, were included in the analysis. When available, histopathology was reviewed. RESULTS: Among the various causes of gastroenteritis, both infectious and non-infectious, our findings revealed that 25.46% of the cases were linked to viral pathogens. This included a significantly higher percentage of pediatric patients (72.73%) when compared to adults (27.07%), with a p-value of 0.015. Norovirus genogroups I and II emerged as the most frequently detected viruses across all age groups, with a significant prevalence among adults. No discernible gender-based differences were observed. The histopathological findings included inflammation, ulceration, erosion, architectural distortion, and the pathognomonic viral inclusion bodies associated with adenovirus. CONCLUSION: Our comprehensive analysis of viral gastroenteritis cases highlights the substantial burden of this condition, particularly among pediatric patients. Norovirus emerges as a prevalent culprit which emphasizes the importance of vigilant surveillance and timely diagnosis, especially in settings where outbreaks are common.

Diagnosing viral gastro-enteritis using the fully automated sample-in, result-out STARlet All in one system (AIOS).

The STARlet All-In-One system is a modular platform that integrates the complete molecular diagnostic workflow from nucleic acid extraction of clinical samples to PCR set-up and amplification. The platform was evaluated in comparison with laboratory developed tests (LDT) on fecal samples from patients with suspected viral gastro-enteritis. In a retrospective study, 72 positive samples were analysed, including all pathogens detected by the Seegene Allplex™ GI-virus assay, adenovirus, astrovirus, norovirus GI and GII, sapovirus, and rotavirus. Concordant results were obtained for 69 samples (96 %). Three discordant results were observed, one norovirus GII positive that gave an invalid result in the AIOS and two samples that were negative in the AIOS. One adenovirus positive that was subtyped as a genotype 2 virus, which is not associated with gastro-enteritis, and a sapovirus. In the prospective part of the study, 661 fecal samples were included. A total of 61 positive samples were detected, of which 60 were also detected by the AIOS. One norovirus GII positive sample (CT 35.2) was tested negative in the AIOS. Two additional sapovirus positive samples, CT 37 and 38, were detected by the AIOS but not by the LDT. The STARlet All-In-One platforms results in an automated molecular workflow with reduced hands-on time and enables running assays during out of office hours. Application of the Seegene Allplex™ GI-virus assay showed excellent concordance to the current diagnostic LDT. In a prospective comparison, only three discordant results were observed, all with CT values over 35 and therefore unlikely of clinical relevance.

Rotavirus and adenovirus in children evaluated for viral gastroenteritis at a single healthcare center in the Eastern Province of Saudi Arabia: A perspective of two decades.

BACKGROUND: The aim of this study was to determine the distribution of rotavirus and adenovirus in pediatric patients evaluated for viral gastroenteritis in a hospital in the Eastern Province of Saudi Arabia for 22 years. MATERIALS AND METHODS: This was a retrospective study based in a secondary healthcare center in Saudi Arabia. Laboratory and demographic data were collected from hospital records for all pediatric patients (up to 14 years old) evaluated for viral gastroenteritis by rotavirus/adenovirus antigen detection kit from January 2000 to December 2022. Data were analyzed utilizing SPSS version 28.0. Categorical data were presented as frequency and percentages, whereas mean and standard deviations were computed for continuous variables. Chi-square test and t-test were used to determine statistical significance. RESULTS: The overall yields of antigen detection were 13.6% for rotavirus and 2.6% for adenovirus. Coinfection with both viruses was documented in 0.5% of the study population. Rotavirus was persistently detected in the past two decades with varying frequency, but the detection of adenovirus showed intervals of at least three consecutive years of zero confirmed cases. Before 2013, when the rotavirus vaccine was introduced in Saudi Arabia, rotavirus was much more prevalent than adenovirus (30% compared to 3.8% in 2010), but they became equally prevalent a decade after the introduction of the vaccine. Rotavirus gastroenteritis showed three different peaks in the year, in March, July, and December. Each peak was followed by a gradual decrease in prevalence before the next peak. Adenovirus, in contrast, was detected consistently around the year at rates between 2% and 5%. CONCLUSION: Rotavirus and adenovirus gastroenteritis have changed in prevalence in the past two decades. We found distinct seasonal patterns associated with rotavirus and adenovirus gastroenteritis. The utilization of virological testing for pediatric gastroenteritis with syndromic testing panels is to be encouraged to improve the knowledge of the true prevalence of enteric viruses.

Changes in the epidemiology and clinical characteristics of viral gastroenteritis among hospitalized children in the Mainland of China: a retrospective study from 2016 to 2020.

BACKGROUND: Acute gastroenteritis (AGE) causes significant morbidity in children worldwide; however, the disease burden of children hospitalized with viral gastroenteritis in China has been rarely described. Through this study, we analyzed the data of hospitalized children with viral gastroenteritis to explore the changes in the epidemiology and clinical characteristics of viral gastroenteritis in the mainland of China. METHODS: Data were extracted from Futang Children's Medical Development Research Center (FRCPD), between 2016 and 2020, across 27 hospitals in 7 regions. The demographics, geographic distribution, pathogenic examination results, complications, hospital admission date, length of hospital stays, hospitalization charges and outcomes were collected and analyzed. RESULTS: Viral etiological agents included rotavirus (RV), adenovirus (ADV), norovirus (NV) and coxsackievirus (CV) that were detected in 25,274 (89.6%), 1,047 (3.7%), 441 (1.5%) and 83 (0.3%) cases. There was a higher prevalence of RV and NV infection among children younger than 3 years of age. RV and NV had the highest detection rates in winter, while ADV in summer. Children with viral gastroenteritis were often accompanied by other diseases, such as myocardial diseases (10.98-31.04%), upper respiratory tract diseases (1.20-20.15%), and seizures (2.41-14.51%). Among those cases, the co-infection rate with other pathogens was 6.28%, with Mycoplasma pneumoniae (M. pneumoniae), Epstein-Barr virus (EBV), and influenza virus (FLU) being the most common pathogens. The median length of stay was 5 days, and the median cost of hospitalization corresponded to587 US dollars. CONCLUSIONS: This finding suggests that viral gastroenteritis, especially those caused by RV, is a prevalent illness among younger children. Co-infections and the presence of other diseases are common. The seasonality and regional variation of viral etiological agents highlight the need for targeted prevention and control measures. Although viral gastroenteritis rarely leads to death, it also results in a significant economic burden on healthcare systems.

Trends in the detection of viruses causing gastroenteritis over a 10-year period and impact of nonpharmaceutical interventions.

BACKGROUND: Viral gastroenteritis continues to be a leading cause of death in low-income countries. The impact of nonpharmaceutical interventions (NPIs) on the transmission of gastroenteritis-causing viruses during the COVID-19 pandemic is understudied. OBJECTIVES: To investigate the 10-year trends of enteric viruses and estimate the impact of implementing and mitigating NPIs. STUDY DESIGN: Data regarding norovirus, rotavirus, adenovirus, astrovirus, and sapovirus detection were collected from five Korean hospitals between January 2013 and April 2023. We compared positivity between the pre-pandemic, pandemic, and post-pandemic periods. The causal effects of implementing and mitigating NPIs were quantified using the Bayesian Structural Time Series (BSTS) model. RESULTS: Norovirus was most frequently detected (9.9 %), followed by rotavirus (6.7 %), adenovirus (3.3 %), astrovirus (1.4 %), and sapovirus (0.6 %). During the pandemic, the positivity of all five viruses decreased, ranging from -1.0 % to -8.1 %, with rotavirus showing the greatest decrease. In the post-pandemic period, positivity rebounded for all viruses except for rotavirus. The BSTS model revealed that NPI implementation negatively affected the detection of all five viruses, resulting in reductions ranging from -73.0 % to -91.0 % compared to the prediction, with rotavirus being the least affected. Conversely, NPI mitigation positively affected the detection of all viruses, ranging from 79.0 % to 200.0 %, except for rotavirus. CONCLUSIONS: Trends observed over 10 years show that NPIs have had a major impact on changes in enteric virus detection. The effect of vaccines, in addition to NPIs, on rotavirus detection requires further investigation. Our findings emphasize the importance of NPIs in infection control and prevention.

Clinical severity of enteric viruses detected using a quantitative molecular assay compared to conventional assays in the Global Enteric Multicenter Study.

BACKGROUND: Quantitative molecular assays are increasingly used for detection of enteric viruses. METHODS: We compared the clinical severity using modified Vesikari score (mVS) of enteric viruses detected by conventional assays (enzyme immunoassays [EIA] for rotavirus and adenovirus 40/41 and conventional polymerase chain reaction for astrovirus, sapovirus, and norovirus) and a quantitative molecular assay (TaqMan Array Card [TAC]) among children aged 0-59 months in the Global Enteric Multicenter Study. For rotavirus and adenovirus 40/41, we compared severity between EIA-positive and TAC-positive cases assigned etiologies using different cycle threshold (CT) cutoffs. RESULTS: Using conventional assays, the median (interquartile range) mVS was 10 (8, 11) for rotavirus, 9 (7, 11) for adenovirus 40/41, 8 (6, 10) for astrovirus, sapovirus, and norovirus GII, and 7 (6, 9) for norovirus GI. Compared to rotavirus EIA-positive cases, the median mVS was 2 and 3 points lower for EIA-negative/TAC-positive cases with CT<32.6 and 32.6≤CT<35, respectively (p-value<.0001). Adenovirus 40/41 EIA-positive and EIA-negative/TAC-positive cases were similar, regardless of CT cutoff. CONCLUSIONS: Quantitative molecular assays compared to conventional assays, such as EIA, may influence severity of identified cases, especially for rotavirus. Cutoffs to assign etiology for quantitative assays should be considered in the design and interpretation of enteric virus studies.

The Scope and Impact of Viral Infections in Common Variable Immunodeficiency (CVID) and CVID-like Disorders: A Literature Review.

Common Variable Immunodeficiency (CVID) is a heterogeneous primary immunodeficiency disorder characterised by impaired antibody production, leading to recurrent infections and an increased susceptibility to viral pathogens. This literature review aims to provide a comprehensive overview of CVID's relationship with viral infections, encompassing disease pathogenesis, key presenting features, specific monogenic susceptibilities, the impact of COVID-19, and existing treatment options. The pathogenesis of CVID involves complex immunological dysregulation, including defects in B cell development, antibody class switching, and plasma cell differentiation. These abnormalities contribute to an impaired humoral immune response against viral agents, predisposing individuals with CVID to a broad range of viral infections. Genetic factors play a prominent role in CVID, and monogenic drivers of CVID-like disease are increasingly identified through advanced genomic studies. Some monogenic causes of the CVID-like phenotype appear to cause specific viral susceptibilities, and these are explored in the review. The emergence of the COVID-19 pandemic highlighted CVID patients' heightened predisposition to severe outcomes with viral infections. This review explores the clinical manifestations, outcomes, and potential therapeutic approaches for COVID-19 in CVID patients. It assesses the efficacy of prophylactic measures for COVID-19, including vaccination and immunoglobulin replacement therapy, as well as trialled therapies.

Molnupiravir inhibits human norovirus and rotavirus replication in 3D human intestinal enteroids.

Human norovirus (HuNoV) and human rotavirus (HRV) are the leading causes of gastrointestinal diarrhea. There are no approved antivirals and rotavirus vaccines are insufficient to cease HRV associated mortality. Furthermore, treatment of chronically infected immunocompromised patients is limited to off-label compassionate use of repurposed antivirals with limited efficacy, highlighting the urgent need of potent and specific antivirals for HuNoV and HRV. Recently, a major breakthrough in the in vitro cultivation of HuNoV and HRV derived from the use of human intestinal enteroids (HIEs). The replication of multiple circulating HuNoV and HRV genotypes can finally be studied and both in the same non-transformed and physiologically relevant model. Activity of previously described anti-norovirus or anti-rotavirus drugs, such as 2'-C-methylcytidine (2CMC), 7-deaza-2'-C-methyladenosine (7DMA), nitazoxanide, favipiravir and dasabuvir, was assessed against clinically relevant human genotypes using 3D-HIEs. 2CMC showed the best activity against HuNoV GII.4, while 7DMA was the most potent antiviral against HRV. We identified the anti-norovirus and -rotavirus activity of molnupiravir and its active metabolite, N4-hydroxycytidine (NHC), a broad-spectrum antiviral used to treat coronavirus disease 2019 (COVID-19). Molnupiravir and NHC inhibit HuNoV GII.4, HRV G1P[8], G2P[4] and G4P[6] in 3D-HIEs with high selectivity and show a potency comparable to 2CMC against HuNoV. Moreover, molnupiravir and NHC block HRV viroplasm formation, but do not alter its size or subcellular localization. Taken together, molnupiravir inhibits both HuNoV and HRV replication, suggesting that the drug could be a candidate for the treatment of patients chronically infected with either one of these diarrhea causing viruses.

Common and Potential Emerging Foodborne Viruses: A Comprehensive Review.

Human viruses and viruses from animals can cause illnesses in humans after the consumption of contaminated food or water. Contamination may occur during preparation by infected food handlers, during food production because of unsuitably controlled working conditions, or following the consumption of animal-based foods contaminated by a zoonotic virus. This review discussed the recent information available on the general and clinical characteristics of viruses, viral foodborne outbreaks and control strategies to prevent the viral contamination of food products and water. Viruses are responsible for the greatest number of illnesses from outbreaks caused by food, and risk assessment experts regard them as a high food safety priority. This concern is well founded, since a significant increase in viral foodborne outbreaks has occurred over the past 20 years. Norovirus, hepatitis A and E viruses, rotavirus, astrovirus, adenovirus, and sapovirus are the major common viruses associated with water or foodborne illness outbreaks. It is also suspected that many human viruses including Aichi virus, Nipah virus, tick-borne encephalitis virus, H5N1 avian influenza viruses, and coronaviruses (SARS-CoV-1, SARS-CoV-2 and MERS-CoV) also have the potential to be transmitted via food products. It is evident that the adoption of strict hygienic food processing measures from farm to table is required to prevent viruses from contaminating our food.

Classic human astrovirus 4, 8, MLB-3, and likely new genotype 5 sublineage in stool samples of children in Nigeria.

Human astrovirus (HAstV) is a nonenveloped RNA virus and has been implicated in acute gastroenteritis among children and elderly. However, there exists a substantial dearth of information on HAstV strains circulating in Nigeria. Viral-like particles were purified from archived 254 stool samples of children with acute flaccid paralysis between January and December 2020 from five states in Nigeria, using the NetoVIR protocol. Extracted viral RNA and DNA were subjected to a reverse transcription step and subsequent random polymerase chain reaction amplification. Library preparation and Illumina sequencing were performed. Using the virome paired-end reads pipeline, raw reads were processed into genomic contigs. Phylogenetic and pairwise identity analysis of the recovered HAstV genomes was performed. Six near-complete genome sequences of HAstV were identified and classified as HAstV4 (n = 1), HAstV5 (n = 1), HAstV8 (n = 1), and MLB-3 (n = 3). The HAstV5 belonged to a yet unclassified sublineage, which we tentatively named HAstV-5d. Phylogenetic analysis of open reading frames 1a, 1b, and 2 suggested recombination events inside the MAstV1 species. Furthermore, phylogenetic analysis implied a geographic linkage between the HAstV5 strain from this study with two strains from Cameroon across all the genomic regions. We report for the first time the circulation of HAstV genotypes 4, 8, and MLB-3 in Nigeria and present data suggestive for the existence of a new sublineage of HAstV5. To further understand the burden, diversity, and evolution of HAstV, increased research interest as well as robust HAstV surveillance in Nigeria is essential.

Screening for viral pathogens in the gastrointestinal tract from cases of sudden unexpected death in infancy at the Tygerberg Medico-legal Mortuary.

Sudden and unexpected death in infancy (SUDI) may be triggered by an external risk or exposure. Intestinal infections with enteric viruses may disrupt the gut and enhance bacterial toxins present in SUDI cases. While diarrhoeal disease deaths have decreased worldwide, approximately half a million deaths still occur in children in Sub- Saharan Africa and South Asia. Furthermore, the role of viral enteropathogens in SUDI cases have not been investigated. The aim of this study was to describe specific viral pathogens in stool samples collected from SUDI cases and age-matched, apparently healthy infants in Cape Town, South Africa. Stool samples were collected from 176 SUDI cases between June 2017 and May 2018. In addition, stool samples were collected from the nappies of 30 age-matched, apparently healthy infants as a control group. Real-time polymerase chain reaction was performed on the stool samples for viral detection. A total of 111 SUDI cases were positive for viruses, with rotavirus (38.6%; 68/176) and norovirus GI and GII (30.0%; 53/176) were prevalent in SUDI cases. Adenovirus Type F was present in only 15.9% (28/176), astrovirus in 9.7% (17/176), and sapovirus in 0.6% (1/176) of cases. In the control samples, norovirus GII was detected most frequently (36.7%; 11/30), followed by rotavirus (33.3%; 10/30), and sapovirus in 6.7% (2/30). While there was no significant association between SUDI cases and enteric viruses, the majority of viruses were significantly associated with the seasons. The study confirms the importance of rotavirus vaccination and describes the significance of norovirus infection in children, post rotavirus vaccine introduction.

Norovirus acute gastroenteritis among US and European travellers to areas of moderate to high risk of travellers' diarrhoea: a prospective cohort study.

BACKGROUND: Acute gastroenteritis (AGE) is a major medical condition for travellers worldwide, particularly travellers to low- and middle-income countries. Norovirus (NoV) is the most common cause of viral AGE in older children and adults, but data on prevalence and impact among travellers is limited. METHODS: Prospective, multi-site, observational cohort study conducted 2015-2017, among adult international travellers from the US and Europe to areas of moderate to high risk of travel-acquired AGE. Participants provided self-collected pre-travel stool samples and self-reported AGE symptoms while travelling. Post-travel stool samples were requested from symptomatic subjects and a sample of asymptomatic travellers within 14days of return. Samples were tested for NoV by RT-qPCR, genotyped if positive, and tested for other common enteric pathogens by Luminex xTAG GPP. RESULTS: Of the 1109 participants included, 437 (39.4%) developed AGE symptoms resulting in an overall AGE incidence of 24.7 per 100 person-weeks (95% CI: 22.4; 27.1). Twenty NoV-positive AGE cases (5.2% of those tested) were identified at an incidence of 1.1 per 100 person-weeks (95% CI: 0.7; 1.7). NoV-positive samples belonged mostly to genogroup GII (18, 85.7%); None of the 13 samples sequenced belonged to genotype GII.4. Clinical severity of AGE was higher for NoV-positive than for NoV-negative cases (mean modified Vesikari Score 6.8 vs 4.9) with more cases classified as severe or moderate (25% vs 6.8%). Eighty percent of NoV-positive participants (vs. 38.9% in NoV-negative) reported at least moderate impact on travel plans. CONCLUSIONS: AGE is a prevalent disease among travellers with a small proportion associated with NoV. Post-travel stool sample collection timing might have influenced the low number of NoV cases detected; however, NoV infections resulted in high clinical severity and impact on travel plans. These results may contribute to targeted vaccine development and the design of future studies on NoV epidemiology.

Diversity of human astroviruses in Germany 2018 and 2019.

Aim of this study was to investigate the molecular diversity of human astroviruses (HAstV) in Germany. A follow-up study was performed with human stool samples collected in 2018-2019, which were genotyped retrospectively. A total of 2645 stool samples, collected between January 2018 and December 2019 from sporadic cases and outbreaks of acute gastroenteritis were analyzed. An algorithm of PCR systems was used to characterize human astrovirus. Human astroviruses were found in 40 samples (positive rate: 1.6%). During the study period, children aged 1-2 years (48%) were most affected by HAstV. Genotyping revealed a number of nine circulating genotypes representing four human Mamastrovirus species. Strain MLB1 was predominant in the study population with a detection rate of 25% followed by HAstV1 with a positive rate of 20%. The diversity of astrovirus genotypes seems to be rather stable in Germany in the last years. A clustering of regionally and/or temporally linked human astroviruses in Germany was not detectable.

Prognostic factors associated with survival and hospitalization time in pediatric canine patients diagnosed with presumptive acute viral gastroenteritis.

Background and Aim: Acute viral gastroenteritis is one of the main causes of hospitalization in dogs during the 1st year of life. This retrospective study aimed to describe a pediatric canine population presumptively diagnosed with acute viral gastroenteritis and to identify potential prognostic factors that influence hospitalization time (HT) and mortality. Materials and Methods: Canine patients up to 12 months of age diagnosed with presumptive acute viral gastroenteritis were searched retrospectively from two veterinary hospitals during a 5-year period (2015-2020). Information regarding patient signalment, prophylactic care, clinical signs, blood test results, presence of systemic inflammatory response syndrome, and additional treatments were recorded to analyze their association with HT and mortality. Only dogs with a complete medical record until death or discharge were included in the study. Results: Ninety-four dogs were identified: 76 dogs (80.9%) survived with a median HT of 5 days (range: 2-16 days) and 18 dogs (19.1%) died with a median HT of 3½ days (range: 1-8 days) after admission. The presence of fever and fresh frozen plasma (FFP) administration was significantly associated with a lower survival rate (p = 0.021 and p = 0.037) in the multivariate analysis. Among survivors, incomplete primo-vaccination, the presence of hematochezia, and FFP administration were considered independent predictors of time to clinical recovery (p = 0.026, p = 0.047, and p = 0.026, respectively), being associated with higher HT. Conclusion: The presence of fever and FFP administration was significantly associated with a lower survival rate. An inadequate primo-vaccination status prior to admission, hematochezia, and FFP administration was associated with longer HT in surviving patients. Further studies are needed to confirm the present results.

Human rotavirus VP4 and VP7 genetic diversity and detection of GII norovirus in Ibadan as Nigeria introduces rotavirus vaccine.

OBJECTIVE: This cross-sectional study investigated the circulating strains of rotavirus and screened for noravirus in Ibadan, Nigeria as the country introduces the rotavirus vaccine into its national immunization program. METHODS: Sixty-five stool samples were collected from children younger than 5 years with clinically diagnosed diarrhea and screened for the presence of rotavirus and norovirus using RT-PCR. Rotavirus-positive samples were further analyzed to determine the G and P genotypes using semi-nested multiplex PCR. RESULTS: The rates of rotavirus and norovirus positivity were 30.8% and 10.8%, respectively, whereas the rate of rotavirus and norovirus mixed infection was 4.6%. G1 was the predominant VP7 genotype, followed by G2, G9, and G1G2G9, whereas the predominant VP4 genotype was P[4], followed by P[6], P[8], and P[9]. The mixed P types P[4]P[8] and P[4]P[6] were also detected. G1P[4] was the most common VP4 and VP7 combination, followed by G2P[4], G1[P6], G1P[8], G2P[6], G2P[9], G9P[6], G2G9P[4], G2P[4]P[6], G1P[4]P[8], G2G9P[8], G1G2G9P[8], and G1[non-typable] P[non-typable], which were detected in at least 5% of the samples. Four samples had a combination of non-typable G and P types. CONCLUSIONS: It is essential to monitor the circulation of virus strains prior to and during the implementation of the immunization program.

Changes in norovirus incidence in Victoria, Australia, during the COVID-19 pandemic, 2020-2021.

There were 142 norovirus positive outbreaks in Victoria for the 2020-2021 calendar years; however, almost half of these (48.6%) occurred in Q1 (January-March) of 2021. For the two-year period, 69.0% of all norovirus positive outbreaks were in childcare settings, and the predominant genotype was GII.P16/GII.2 (64.9%) followed by GII.P31/GII.4_2012 (20.9%). Norovirus incidence was particularly low in 2020 (n = 26) and close to average in 2021 (n = 116), but genotype diversity was low in both years. With the thought that 2022 will approach a more normal aspect to socialising and travel, norovirus incidence in 2022 may be predicted to increase above typical levels.