Astrovirus Infection In Children Research Articles

Molecular characterization of human astrovirus infection in children under 5 years of age with acute gastroenteritis in Tehran, Iran, 2021-2022: co-infection with rotavirus.

Human astroviruses (HAstVs) are considered important causative pathogens of acute gastroenteritis (AGE) in children under 5 years of age worldwide, along with group A rotavirus (RVA), norovirus (NoV), and enteric adenovirus (EAdV). The present study was aimed to both detect HAstV and its co-infections and investigate genetic analysis of circulating HAstV and co-infected virus in hospitalized children under 5 years of age with AGE in Iran. Accordingly, a sum of 200 stool specimens were screened by PCR for HAstV during 2021-2022. The HAstV was found in 0.5% of 200 specimens (n = 1) while was co-infected with RVA. The genetic and phylogenetic analysis indicated HAstV1 genotype, which clustered with viruses from lineage 1b, which has not been previously reported in Iran. The detected RVA strain belonged to G1 lineage II/P[8]-lineage III, which has been reported previously in Iran as the most common strain. The further genetic analysis of RVA VP6 and NSP4 demonstrated an atypical genotype pattern G1P[8]-I1-E2, as a mono-reassortant of a Wa-like genogroup, which appeared to be reassorted with the NSP4 gene of E2 genotype of the G2P[4] DS-1 genogroup. Although the clinical outcomes of the AGE-causing viruses co-infection is not yet entirely clear, it seems that future studies will be helpful to merge clinical and epidemiological data of co-infecting viruses for a more accurate medical and clinical relevance in symptomatic children.

Astrovirus gastroenteritis in children

The article provides a detailed analysis of modern publications focused on a studies an astrovirus gastroenteritis. Based on our own examination of 3470 children with acute intestinal infections aged from 1 month to 1 8 years old, who were treated at the Children's Research and Clinical Center for Infectious Diseases, FMBA of Russia, St. Petersburg, from May 201 7 to July 2018 a detailed description of the characteristic epidemiological, clinical and laboratory features of the disease is given. It was shown, that astroviruses remain a significant causative agent of acute intestinal infections in children, accounting for 1.36% of all cases of disease. Among the combined forms of astrovirus infection, associations with rotaviruses, noroviruses and campylobacter spp. are most common. It was established, that the disease is more often observed in boys aged 1 to 3 years. Clinical course of astrovirus infection in children is characterized by an acute or gradual onset with repeated vomiting, moderate intoxication and symptoms of gastroenteritis. Due to the lack of pathognomonic clinical and laboratory features of the course of viral gastroenteritis, diagnosis is necessary using laboratory methods including molecular genetic research methods.

Occurrence of human astrovirus associated with gastroenteritis among Congolese children in Brazzaville, Republic of Congo

IntroductionAcute viral gastroenteritis is a major public health concern, especially among children younger than 5 years of age. The aim of this study was to determine the occurrence of human astrovirus infection in children with acute gastroenteritis. MethodsStool specimens were collected from 506 children under 5 years of age hospitalized with acute diarrhoea (289 male and 208 female), and human astrovirus was investigated by RT-PCR. Associations of socio-demographic, clinical, and behavioural conditions with infection were analysed. ResultsThe overall prevalence of human astrovirus was found to be 10.3%. The mean age of positive cases was 12.41 ± 6.21 months and this was associated with infection (p = 0.013). Children >18 months of age were at three times the risk of infection when compared to those aged 0–6 months (odds ratio (OR) 3.19, 95% confidence interval (CI) 1.15–8.88; p = 0.026). Children living in houses with more than one room (OR 0.60, 95% CI 0.28–0.96; p = 0.036) and mothers using treated water (OR 0.47, 95% CI 0.25–0.86; p = 0.015) were associated with reduced infection. ConclusionsIn this study, infection with astrovirus was common in acute gastroenteritis cases among children younger than 5 years of age. Drinking treated water and living in non-crowded environments protected the children from infection.

Astrovirus infection in children in lagos, Nigeria.

A preliminary investigation was conducted to screen for astrovirus in Lagos. Two hundred and fifteen (215) faecal samples collected from children under 5 years old with diarrhoea (161) and without diarrhoea (54) admitted at paediatric clinics in Lagos State were studied. The stool specimens were examined for the presence of human astrovirus antigen using a monoclonal antibody-based ELISA (Astrovirus RIDASCREEN(®) r-Biopharm, Germany) technique. Astrovirus was detected in 40.4 percent (65/161) of the diarrhoeal stools compared to 11.1 percent (6/54) of the control specimens. Astrovirus was found to infect younger children and about three quarter of the children infected was under 12 months of age. The prevalence of infection decreases with age group and was statistically significant (P = 0.0470). Although, prevalence of infection is more in males than females but this is not significant. This study shows that astrovirus is an important agent of acute gastroenteritis among children in Lagos state.

Epidemiology of astrovirus infection in children

Human astrovirus (HAstV) is a major cause of acute diarrhea among children, resulting in outbreaks of diarrhea and occasionally hospitalization. Improved surveillance and application of sensitive molecular diagnostics have further defined the impact of HAstV infections in children. These studies have shown that HAstV infections are clinically milder (diarrhea, vomiting, fever) than infections with other enteric agents. Among the 8 serotypes of HAstV identified, serotype 1 is the predominant strain worldwide. In addition to serotype 1, the detection rate of HAstV types 2 to 8 has increased by using newly developed assays. HAstV is less common compared with other major gastroenteritis viruses, including norovirus and rotavirus; however, it is a potentially important viral etiological agent with a significant role in acute gastroenteritis. A better understanding of the molecular epidemiology and characteristics of HAstV strains may be valuable to develop specific prevention strategies.

Molecular characterization of astrovirus infection in children with diarrhea in Beijing, 2005–2007

Human astroviruses (HAstVs) have been recognized as one of the major causes of acute gastroenteritis in children. To provide more insight into the prevalence of HAstV gastroenteritis in China, 664 fecal samples were collected from children affected with acute gastroenteritis in Beijing from March 2005 to November 2007. The samples were analyzed genetically. All eight serotypes (genotypes) of HAstVs were screened using RT‐PCR assays targeting the ORF2 region in the study. The assays detected HAstVs in 52 (7.8%) of the patients, with HAstV‐1 (50/52) being the dominant genotype during the study period. Two minor genotypes, HAstV‐6 and HAstV‐3, were also detected. Partial sequencing of the 50 HAstV‐1 strains showed that the homology of the nucleotide sequence of the ORF1a region between these strains was 88.4–100%, whereas the homology of the amino acid sequences was 95.6–100%. In the ORF2 partial region, the nucleotide identities ranged from 91.5% to 100%, and amino acid identities ranged from 97.3% to 100%. The identity of the whole genome sequence between four randomly examined HAstV‐1 strains was 91–99%. No recombination events were observed in HAstVs in this study. The findings of this study will provide baseline data for HAstVs surveillance and control. J. Med. Virol. 82:415–423, 2010. © 2010 Wiley‐Liss, Inc.

<![CDATA[<B>Astrovirus infection in children living in the Central West region of Brazil</B>]]>

This study presents data regarding the circulation of astrovirus in Goiânia-GO and Brasília-DF. These viruses were detected in fecal samples from hospitalized children up to five years old with and without acute gastroenteritis. A total of 1244 fecal samples were collected in two periods, 1994 to 1996 (Brasília) and 1998 to 2002 (Goiânia and Brasília), and were analyzed for viral RNA using the reverse transcription-polymerase chain reaction (RT-PCR). Positivity rates of 4.3 and 0.5% for astrovirus were observed in children with acute gastroenteritis and those without gastroenteritis, respectively. Among children with gastroenteritis no statistically significant difference was seen with regards to viral positivity rates in relation to gender and age. However, a higher incidence rate was observed for children from Brasília aged 36 months or more. Overall, astroviruses occurred predominantly from September to March in the two cities, suggesting a seasonal pattern for these viruses which coincides with the highest relative air humidity period. The results of this study highlight the importance of astrovirus as an etiologic agent of acute gastroenteritis in children of the Central West region of Brazil.

Astrovirus infection in children living in the Central West region of Brazil

This study presents data regarding the circulation of astrovirus in Goiânia-GO and Brasília-DF. These viruses were detected in fecal samples from hospitalized children up to five years old with and without acute gastroenteritis. A total of 1244 fecal samples were collected in two periods, 1994 to 1996 (Brasília) and 1998 to 2002 (Goiânia and Brasília), and were analyzed for viral RNA using the reverse transcription-polymerase chain reaction (RT-PCR). Positivity rates of 4.3 and 0.5% for astrovirus were observed in children with acute gastroenteritis and those without gastroenteritis, respectively. Among children with gastroenteritis no statistically significant difference was seen with regards to viral positivity rates in relation to gender and age. However, a higher incidence rate was observed for children from Brasília aged 36 months or more. Overall, astroviruses occurred predominantly from September to March in the two cities, suggesting a seasonal pattern for these viruses which coincides with the highest relative air humidity period. The results of this study highlight the importance of astrovirus as an etiologic agent of acute gastroenteritis in children of the Central West region of Brazil.

One-year survey of astrovirus infection in children with gastroenteritis in a large hospital in Hungary: occurrence and genetic analysis of astroviruses.

Human astroviruses (HAstV) are the causative agents of viral gastroenteritis mainly in children worldwide. This study investigated the epidemiology and genotype diversity of HAstVs detected in children admitted to hospital with gastroenteritis in Hungary. Stool samples were collected from children with diarrhea at the Municipal "Szent László" Hospital, Budapest, Hungary, between January 2002 and December 2002. Of 2,758 samples, 607 were negative for both rotaviruses and bacterial pathogens and were tested for astroviruses using a reverse transcriptase-polymerase chain reaction (RT-PCR) targeting the open reading frame (ORF2), capsid region. Astrovirus was detected in 10 samples (1.6%) by RT-PCR. Astrovirus infection was more frequent among children 49 to 60 months of age. Genotyping of positive samples was performed by type-specific RT-PCR and confirmed by sequence analysis. Phylogenetic analysis was performed using a 203 nucleotide consensus length of the 3'-end of the capsid gene. Type-specific RT-PCR and sequence analysis detected genotypes 1 (50%), 4 (30%), 3 (10%), and 8 (10%) among the children admitted to hospital. Genotype 1 was the predominant genotype, but genotypes 3, 4, and 8 were also present indicating the importance of emerging genotype 8 infections. Two distinct genotype 4 variants were observed during this study. Sequence analysis confirmed type-specific RT-PCR results in the capsid region. This is the first comprehensive report on the occurrence of HAstV infections in Central/Eastern Europe.

Astrovirus infection in children.

Public health concerns related to enteric viral agents, such as astroviruses and caliciviruses, include their ability to cause sporadic diarrhea, large outbreaks of gastroenteritis, and hospitalizations or deaths resulting from vomiting, diarrhea, and dehydration. Improved surveillance and application of sensitive molecular assays has increased awareness of these enteric pathogens and reduced the 'diagnostic gap' or unknown causes of non-bacterial gastroenteritis. Molecular assays have been applied to further describe the epidemiology of human astroviruses from a variety of geographic areas. The burden of astrovirus infections compared with other enteric viral agents, including rotaviruses, caliciviruses, and enteric adenoviruses have been reported. New methods for detection of astroviruses such as reverse transcription-polymerase chain reaction and molecular typing methods have advanced the understanding of the epidemiology. Additional molecular studies have described the protein processing mechanisms of this single-stranded RNA virus. Astroviruses are increasingly recognized as significant gastrointestinal pathogens. The understanding of molecular epidemiology and molecular processing of the virus may lead to specific prevention strategies.

Infección por astrovirus en niños con gastroenteritis

We report here a 2 year study (1997-1998) of astrovirus infection in children admitted to our hospital. The epidmioligical and clinical features of the infection were also investigated. A total of 1.815 stool specimens were tested during a two-year period (january 1997- december 1998). They were collected from children less than 3 years of age admitted to La Paz Hospital (Madrid) with acute gastroenteritis. We used a monoclonal antibody-based enzyme inmunoassay (IDEIA Astrovirus, DAKO) to detect astrovirus antigen in faecal samples. Astroviruses were detected in 79 of the 1.815 analysed samples. This represented an incidence of 4,3%. The main symptom of infection was watery diarrhoea, and it was often associated with vomiting and fever. The majority of astrovirus infection occurred between the coldest months of the year. Children under a year of age were the most susceptible population. There was a considerable number of patients (62%) who develop the infection after 72 hours of admission. The rate of detection reported here illustrates the importance of this pathogen in childhood diarrhoea, so we recommend its screening on a routine basis.

Improved sensitivity of astrovirus-specific RT-PCR following culture of stool samples in CaCo-2 cells.

During an epidemiological study on the incidence of astrovirus infection in children hospitalized with acute gastroenteritis, a Northern hybridization method was used to screen stool samples for astrovirus RNA. Positive results were confirmed using reverse transcriptase-polymerase chain reaction (RT-PCR), which showed surprisingly low sensitivity. The low sensitivity of the RT-PCR method was considered likely to be due to the presence of non-specific inhibitors. To develop and use a simple culture method to improve the sensitivity of diagnosis of astrovirus in clinical stool samples using RT-PCR. Stool samples from children hospitalized with acute gastroenteritis were screened for astrovirus using Northern hybridization. The presence of astrovirus RNA was then confirmed using an astrovirus-specific RT-PCR. Hybridization positive samples that failed to generate an RT-PCR product were cultured in CaCO-2 cells for 48 h. RNA was isolated from cultures and re-tested using the same RT-PCR method. Using Northern hybridization, human astroviruses were detected in the stools of 31 patients and confirmed by RT-PCR in 16 samples. RNA extracted directly from 15 faecal specimens could not be amplified by RT-PCR. After culture for 48 h in CaCO-2 cells, RNA extracted from these samples could be amplified and confirmed the presence of astrovirus in all 15 specimens. Development of a simplified culture method for astrovirus positive faecal specimens improved the sensitivity of astrovirus-specific RT-PCR from 52 to 100%. The technique should be of value as a confirmatory test in surveys of human astrovirus infection.

Annual incidence, serotype distribution, and genetic diversity of human astrovirus isolates from hospitalized children in Melbourne, Australia.

The incidence of astrovirus infection in children under 5 years of age hospitalized for acute gastroenteritis in Melbourne, Australia, during 1995 was determined. Astrovirus was detected in 16 fecal specimens by Northern (RNA) dot blot analysis of RNA isolated from feces with an astrovirus-specific cDNA probe. The incidence of astrovirus infection was determined as 4.2% (16 of 378 total samples) compared with rates of 63.2, 3.7, and 4.2% for rotavirus, adenovirus, and all bacterial pathogens, respectively. Astrovirus was detected during the winter season and mainly in infants between 6 and 12 months of age. Serotyping of samples was carried out by reverse transcriptase PCR and direct sequencing of a 348-bp region of the capsid protein gene. Type 1 strains predominated (11 of 13 typeable samples), although type 4 isolates were also detected. Astrovirus was retrospectively identified in 13 fecal samples collected from hospitalized infants between 1980 and 1985 and shown to contain small viruses by electron microscopy. Type 1 isolates were again the most common, although a type 5 strain was also found. Comparative sequence analysis indicated that type 1 astroviruses exhibited up to 7% sequence divergence over a 15-year period; however, all mutations were silent. The incidence of astrovirus reported here indicates that the virus is a significant cause of severe diarrhea in young children. The genetic analysis also provides important molecular epidemiological information relevant to the development of preventative therapies.