First detection of human astrovirus in gastroenteritis outbreak in Hungary

2011 ◽  
Vol 152 (2) ◽  
pp. 45-50 ◽  
Author(s):  
Péter Pankovics ◽  
Ákos Boros ◽  
Melinda Rovács ◽  
Erika Nagy ◽  
Erika Krisztián ◽  
...  

Human astroviruses are one of the known pathogens of gastroenteritis in infants, children and rarely in elderly. It causes 4.2-7.3% of the sporadic gastroenteritis cases with diarrhea and vomiting in children. The etiological role of astrovirus has not been confirmed yet in outbreaks of gastroenteritis in Hungary. Aims: The first description of the detection and molecular epidemiology of astrovirus in outbreaks of gastroenteritis in Hungary. Materials and methods: Stool samples originated from Komárom-Esztergom County, from a day-care center (nursery) where a gastroenteritis outbreak occurred in June, 2010. Astrovirus was detected by RT-PCR methods. The nucleotide sequence of the nearly complete genome was sequenced. Clinical and epidemiological data were collected by epidemiological investigation. Results: Out of the 29 exposed persons (24 children and 5 adults) 7 (24.1%) children had gastroenteritis with diarrhea, and vomiting in one case, in the period of June 4-15, 2010. Bacterial pathogens, rotavirus, adenovirus and norovirus were not detected, but genotype 1 astrovirus could be identified in 3 (42.8%) stool samples (HQ398856). The nucleotide sequence of the astrovirus ORF1a/ORF1b/ORF2/3’UTR regions was determined. The source of the outbreak was presumably the firstly recognized ill child and the virus was spread by fecal-oral route with direct contact in the children community. Conclusions: Epidemiologic and clinical characteristics of the astrovirus outbreak in the nursery are described in details to prove that the possible etiological role of astroviruses in viral gastroenteritis which should not forget in order after rotaviruses, caliciviruses (norovirus and sapovirus) and enteric adenoviruses. Orv. Hetil., 2011, 152, 45–50.

mSphere ◽  
2019 ◽  
Vol 4 (6) ◽  
Author(s):  
Francisco J. Pérez-Rodriguez ◽  
Gael Vieille ◽  
Lara Turin ◽  
Soner Yildiz ◽  
Caroline Tapparel ◽  
...  

ABSTRACT Human astroviruses (HAstV) are among the most common causative agents of viral gastroenteritis, especially in children, and extraintestinal manifestations have also been described. These viruses are transmitted by the fecal-oral route, implying that stool composition and the gut microbiota may impact their ability to remain infectious. For some enteric viruses, individual bacterial envelope components and other polysaccharide-containing molecules, which are abundant in stools, have been shown to enhance capsid stability. However, the role of the complex stool environment and, most importantly, the role of interindividual differences have been poorly studied. We used HAstV as a model to investigate how the stool environment in itself, its interindividual variability, and some specific stool components could affect HAstV stability and infectivity. Using two different HAstV genotypes, we found that stools as a whole modulate astrovirus infectivity not only in an individual-dependent manner but also in a manner that depends on the viral genotype. A virus-protective effect was observed after incubation with various Gram-positive and Gram-negative bacteria as well as with bacterial components, such as lipopolysaccharide and peptidoglycan. These results were further confirmed in human intestinal tissues, a more physiologically relevant system. Astrovirus infectivity was also preserved by mucin, a major component of intestinal mucus. We further confirmed that these components stabilize the viral capsid. These results show that although HAstV benefits from the stabilizing effect of fecal components, the complexity and variability of the stool composition and the multiple potential interactions may explain the interindividual differences in viral transmission observed in real life. IMPORTANCE To ensure transmission, enteric viruses must maintain their infectivity during the various environmental challenges that they face in transit within and between hosts. Increased knowledge of the factors affecting enteric virus survival may help to control their transmission. This study reveals that specific fecal bacterial components preserve classic human astrovirus infectivity by stabilizing viral particles. However, the outcomes of stool-virus interactions are very variable, ranging from protection to a reduction of viral infectivity, depending on the viral genotype and the individual from whom the stool has been collected. We show that the transmissibility of enteric viruses is dependent on the intestinal contents of the infected individual and highlight the complex multiple interactions that could explain the stochastic nature of enteric virus transmission in humans.


2009 ◽  
Vol 90 (12) ◽  
pp. 2965-2972 ◽  
Author(s):  
A. Kapoor ◽  
L. Li ◽  
J. Victoria ◽  
B. Oderinde ◽  
C. Mason ◽  
...  

Diarrhoea remains a significant cause of morbidity and mortality in developing countries where numerous cases remain without identified aetiology. Astroviruses are a recently identified cause of animal gastroenteritis which currently includes two species suspected of causing human diarrhoea. Using pan-astrovirus RT-PCR, we analysed human stool samples from different continents for astrovirus-related RNA sequences. We identified variants of the two known human astrovirus species plus, based on genetic distance criteria, three novel astrovirus species all distantly related to mink and ovine astroviruses, which we provisionally named HMOAstV species A–C. The complete genome of species A displayed all the conserved characteristics of mammalian astroviruses. Each of the now three groups of astroviruses found in human stool (HAstV, AstV-MLB and HMOAstV) were more closely related to animal astroviruses than to each other, indicating that human astroviruses may periodically emerge from zoonotic transmissions. Based on the pathogenic impact of their closest phylogenetic relatives in animals, further investigations of the role of HMOAstV, so far detected in Nigeria, Nepal and Pakistan, in human gastroenteritis are warranted.


Viruses ◽  
2020 ◽  
Vol 12 (10) ◽  
pp. 1157
Author(s):  
Sandra Niendorf ◽  
Mirko Faber ◽  
Andrea Tröger ◽  
Julian Hackler ◽  
Sonja Jacobsen

Human norovirus accounts for the majority of viral gastroenteritis cases worldwide. It is a fast evolving virus generating diversity via mutation and recombination. Therefore, new variants and new recombinant strains emerge in the norovirus population. We characterized norovirus positive stool samples from one intensively studied district Märkisch-Oderland state Brandenburg with the samples from other states of Germany in order to understand the molecular epidemiological dynamics of norovirus outbreaks in Germany 2018. PCR systems, Sanger sequencing, and phylogenetic analyses were used for genotyping. Noroviruses of 250 outbreaks in Germany were genotyped, including 39 outbreaks for the district Märkisch-Oderland. Viral diversity in Märkisch-Oderland as compared to Germany was similar, but not identical. The predominant genogroup in Germany was GII with predominate genotype GII.P16-GII.4 Sydney, whereas GII.P31-GII.4 Sydney was the most frequent in Märkisch-Oderland. Genogroup I viruses were less frequently detected, regional and national. Within the sequences of GII.4 recombinants, two distinct clusters were identified with outbreaks from Märkisch-Oderland. Further analysis of sequence data and detailed epidemiological data are needed in order to understand the link between outbreaks in such clusters. Molecular surveillance should be based on samples collected nationally in order to trace comprehensive virus distribution and recombination events in virus population.


2004 ◽  
Vol 132 (4) ◽  
pp. 737-743 ◽  
Author(s):  
L. MAUNULA ◽  
S. KALSO ◽  
C.-H. VON BONSDORFF ◽  
A. PÖNKÄ

In July 2001, an outbreak of gastroenteritis occurred in Helsinki among children and adults after bathing in an outdoor wading pool. The epidemiological survey revealed that at least 242 persons were affected. Microbiological testing of both patient stool samples and of the pool water revealed the presence of two different gastroenteritis viruses: a norovirus (NV) and an astrovirus. Amplicon sequencing of the NV samples showed nucleotide sequence identity between the virus from patients and the water. After changing the pool water and the sand at the bottom of the pool followed by shock chlorination, no virus could be detected in the water. However, NV was continuously detected in the water outlet well as much as 8 months after the incident. Here we show how molecular methods aided in tracing the source of the epidemic and in finding the causative pathogens both in patients and in the environment.


2021 ◽  
Author(s):  
Noemi Navarro-Lleó ◽  
Cristina Santiso-Bellón ◽  
Susana Vila-Vicent ◽  
Noelia Carmona-Vicente ◽  
Roberto Gozalbo-Rovira ◽  
...  

Noroviruses are the leading cause of sporadic cases and outbreaks of viral gastroenteritis. For more than 20 years most norovirus infections have been caused by the pandemic genotype GII.4, yet recent studies have reported the emergence of recombinant strains in many countries. In the present study, 4,950 stool samples collected between January 2016 and April 2020 in Valencia (Spain) from patients with acute gastroenteritis were analyzed to investigate the etiological agent. Norovirus was the most frequently detected enteric virus with a positive rate of 9.5% (471/4,950). Among 224 norovirus strains characterized, 175 belonged to genogroup GII and 49 to genogroup GI. Using dual genotyping based on sequencing the ORF1/ORF2 junction region we detected 25 different capsid-polymerase type associations. The most common GII capsid genotype was GII.4 Sydney 2012, followed by GII.2, GII.3, GII.6 and GII.17. A high prevalence of recombinant strains (90.4%) was observed among GII infections between 2018 and 2020. GII.4 Sydney[P16] was the predominant genotype from 2019 to 2020. In addition, GII.P16 polymerase was found harboring within six different capsid genes. A new subcluster of GII.4 Sydney associated with the P31 polymerase was identified by phylogenetic analysis. GI.4 and GI.3 were the predominant genotypes in genogroup GI, in which recombinant strains were also found, such as GI.3[P10], GI.3[P13] and GI.5[P4]. Interestingly, the GI.3[P10] strain could represent a new capsid genotype. This study shows the extensive diversity of recombinant noroviruses circulating in Spain and highlights the role of recombination events in the spread of noroviruses.


2017 ◽  
Vol 96 (6) ◽  
pp. 92-98 ◽  
Author(s):  
I.N. Protasova ◽  
◽  
S.V. Domracheva ◽  
O.Yu. Volkova ◽  
V.A. Kalenskij ◽  
...  

2019 ◽  
Vol 31 (1) ◽  
pp. 87-92

Rotaviruses are regarded as the most common cause of viral gastroenteritis and are responsible for considerable morbidity and mortality among children especially under five years of age worldwide. In developing countries like Myanmar, where diarrhoea is in the priority childhood disease, rotavirus surveillance and detection of rotavirus genotypes are utmost important. A hospital-based, cross-sectional descriptive study was conducted at Yangon Children‟s Hospital among under five children admitted for acute diarrhoea from January to October 2016. This study includes detection of Group A rotavirus antigen by commercial enzyme-linked immunosorbent assay (ELISA) and genotyping by multiplex RT-PCR. From a total of 488 collected samples, rotavirus antigen was detected in 219 samples (45%). Rotavirus diarrhoea was most common among the age of 6-11 months (38.8%) followed by 12-23 months (37.9%). The results showed that boys were more commonly affected than girls. Detection of rotavirus positivity was peak in February (57.6 %). Out of 219 stool samples with positive ELISA result, 40 stool samples with high optical density value were proceeded for further determination of G and P genotypes. Regarding distribution of G genotypes, the most common G genotype was G9 which comprised 45%, and that of P genotype was P[8] which comprised 92.5%. Regarding combination of G and P genotypes, the most frequent combination is G9P[8], and it constituted 42.5%. Untypable genotypes were seen in 30% of G and 2.5% of P typing. As rotavirus infection can be prevented by vaccine, WHO recommended that rotavirus vaccination should be included in national immunization program especially in countries where prevalence of rotavirus is high. The distribution of G and P genotypes is important in consideration of appropriate vaccine in pre-vaccination and evaluation of effectiveness of vaccine in post-vaccination period. Therefore, the information on currently circulating genotypes of rotavirus in this study will serve as valuable data for vaccination programme.


Processes ◽  
2021 ◽  
Vol 9 (4) ◽  
pp. 574
Author(s):  
Nikhat Perween ◽  
Sultan Alshehri ◽  
T. S. Easwari ◽  
Vivek Verma ◽  
Md. Faiyazuddin ◽  
...  

Molecules with poor aqueous solubility are difficult to formulate using conventional approaches and are associated with many formulation delivery issues. To overcome these obstacles, nanosuspension technology can be one of the promising approaches. Hence, in this study, the feasibility of mefenamic acid (MA) oral nanosuspension was investigated for pediatric delivery by studying the role of excipients and optimizing the techniques. Nanosuspensions of MA were prepared by adopting an antisolvent precipitation method, followed by ultrasonication with varying concentrations of polymers, surfactants, and microfluidics. The prepared nanosuspensions were evaluated for particle size, morphology, and rheological measures. Hydroxypropyl methylcellulose (HPMC) with varying concentrations and different stabilizers including Tween® 80 and sodium dodecyl sulfate (SLS) were used to restrain the particle size growth of the developed nanosuspension. The optimized nanosuspension formula was stable for more than 3 weeks and showed a reduced particle size of 510 nm with a polydispersity index of 0.329. It was observed that the type and ratio of polymer stabilizers were responsive on the particle contour and dimension and stability. We have developed a biologically compatible oral nanoformulation for a first-in-class drug beautifully designed for pediatric delivery that will be progressed toward further in vivo enabling studies. Finally, the nanosuspension could be considered a promising carrier for pediatric delivery of MA through the oral route with enhanced biological impact.


Nanomaterials ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 743
Author(s):  
Marco Fidaleo ◽  
Stefano Tacconi ◽  
Carolina Sbarigia ◽  
Daniele Passeri ◽  
Marco Rossi ◽  
...  

Vitamin B12 (VitB12) is a naturally occurring compound produced by microorganisms and an essential nutrient for humans. Several papers highlight the role of VitB12 deficiency in bone and heart health, depression, memory performance, fertility, embryo development, and cancer, while VitB12 treatment is crucial for survival in inborn errors of VitB12 metabolism. VitB12 is administrated through intramuscular injection, thus impacting the patients’ lifestyle, although it is known that oral administration may meet the specific requirement even in the case of malabsorption. Furthermore, the high-dose injection of VitB12 does not ensure a constant dosage, while the oral route allows only 1.2% of the vitamin to be absorbed in human beings. Nanocarriers are promising nanotechnology that can enable therapies to be improved, reducing side effects. Today, nanocarrier strategies applied at VitB12 delivery are at the initial phase and aim to simplify administration, reduce costs, improve pharmacokinetics, and ameliorate the quality of patients’ lives. The safety of nanotechnologies is still under investigation and few treatments involving nanocarriers have been approved, so far. Here, we highlight the role of VitB12 in human metabolism and diseases, and the issues linked to its molecule properties, and discuss how nanocarriers can improve the therapy and supplementation of the vitamin and reduce possible side effects and limits.


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