We report on the occurrence and diversity of noroviruses in children (younger than 5 years old of age) from a low-income urban area in Rio de Janeiro, Brazil. Sixty-one stool specimens collected from ...children between 1 and 4 years old with acute diarrhoeic episodes (ADE) and non-ADE were investigated. RT-qPCR and sequencing of PCR products after conventional RT-PCR analysis were performed. Noroviruses were detected in 29 (47.5%) samples: 21 (46.7%) from cases with ADE and 8 (50%) from non-ADE cases. Molecular characterization showed 10 different genotypes circulating in this community between November 2014 and April 2018.
The main objective of this study was to investigate the dynamic of SARS-CoV-2 viral excretion in rectal swab (RS), saliva, and nasopharyngeal swab (NS) samples from symptomatic patients and ...asymptomatic contacts. In addition, in order to evaluate the replication potential of SARS-CoV-2 in the gastrointestinal (GI) tract and the excretion of infectious SARS-CoV-2 from feces, we investigated the presence of subgenomic nucleoprotein gene (N) mRNA (sgN) in RS samples and cytopathic effects in Vero cell culture. A prospective cohort study was performed to collect samples from symptomatic patients and contacts in Rio de Janeiro, Brazil, from May to October 2020. One hundred and seventy-six patients had samples collected at home visits and/or during the follow up, resulting in a total of 1633 RS, saliva, or NS samples. SARS-CoV-2 RNA was detected in 130 (73.9%) patients who had at least one sample that tested positive for SARS-CoV-2. The presence of replicating SARS-CoV-2 in RS samples, measured by the detection of sgN mRNA, was successfully achieved in 19.4% (6/31) of samples, whilst infectious SARS-CoV-2, measured by the generation of cytopathic effects in cell culture, was identified in only one RS sample. Although rare, our results demonstrated the replication capacity of SARS-CoV-2 in the GI tract, and infectious viruses in one RS sample. There is still a gap in the knowledge regarding SARS-CoV-2 fecal-oral transmission. Additional studies are warranted to investigate fecal or wastewater exposure as a risk factor for transmission in human populations.
Diarrheal diseases (DD) have distinct etiological profiles in immune-deficient and immune-competent patients. This study compares detection rates, genotype distribution and viral loads of different ...enteric viral agents in HIV-1 seropositive (n = 200) and HIV-1 seronegative (n = 125) children hospitalized with DD in Rio de Janeiro, Brazil. Except for group A rotavirus (RVA), which were detected through enzyme immunoassay, the other enteric viruses (norovirus NoV, astrovirus HAstV, adenovirus HAdV and bocavirus HBoV) were detected through PCR or RT-PCR. A quantitative PCR was performed for RVA, NoV, HAstV, HAdV and HBoV. Infections with NoV (19% vs. 9.6%; p<0.001), HBoV (14% vs. 7.2%; p = 0.042) and HAdV (30.5% vs. 14.4%; p<0.001) were significantly more frequent among HIV-1 seropositive children. RVA was significantly less frequent among HIV-1 seropositive patients (6.5% vs. 20%; p<0.001). Similarly, frequency of infection with HAstV was lower among HIV-1 seropositive children (5.5% vs. 12.8%; p = 0.018). Among HIV-1 seropositive children 33 (16.5%) had co-infections, including three enteric viruses, such as NoV, HBoV and HAdV (n = 2) and NoV, HAstV and HAdV (n = 2). The frequency of infection with more than one virus was 17 (13.6%) in the HIV-1 negative group, triple infection (NoV + HAstV + HBoV) being observed in only one patient. The median viral load of HAstV in feces was significantly higher among HIV-1 positive children compared to HIV-1 negative children. Concerning children infected with RVA, NoV, HBoV and HAdV, no statistically significant differences were observed in the medians of viral loads in feces, comparing HIV-1 seropositive and HIV-1 seronegative children. Similar detection rates were observed for RVA, HAstV and HAdV, whilst NoV and HBoV were significantly more prevalent among children with CD4+ T lymphocyte count below 200 cells/mm3. Enteric viruses should be considered an important cause of DD in HIV-1 seropositive children, along with pathogens more classically associated with intestinal infections in immunocompromised hosts.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Acute gastroenteritis (AGE) is a significant cause of child mortality worldwide. In Brazil, despite the reduction in infant mortality achieved in recent years, many children still die because of ...undiagnosed AGE. The prevalence, viral load, and circulating genotypes of rotavirus A (RVA), human adenovirus (HAdV), and norovirus GII (NoV GII) were investigated in children with AGE during 12 months in Vitoria, Espírito Santo, Southeastern Brazil. Enteric viruses were detected in stool samples, quantified by quantitative polymerase chain reaction, sequenced, and compared phylogenetically. The overall prevalence was 93.3% (125/134). Cases of single infection (41.8%) and mixed infection (51.5%) were observed; in 21.6% of cases, all the three viruses were detected. RVA had the highest number of copies in all infections. Phylogenetic analysis revealed predominantly the presence of RVA genotype G3, followed by G2 and G9. HAdV clustered within subgroup C, but some samples harbored subgroups A, D, or F. All sequenced NoV‐positive samples clustered within the prevalent genotype GII.4. The high prevalence of RVA, HAdV, and NoV in diarrheal feces clarifies the etiology of AGE in this population, and the presence of RVA in vaccinated children reinforces the importance of monitoring programs to identify the causes of gastroenteritis and contribute to the reliability of diagnosis.
Norovirus stands out as a leading cause of acute gastroenteritis (AGE) worldwide, affecting all age groups. In the present study, we investigated fecal samples from medically attended AGE patients ...received from nine Brazilian states, from 2019 to 2022, including the COVID-19 pandemic period. Norovirus GI and GII were detected and quantified using RT-qPCR, and norovirus-positive samples underwent genotyping through sequencing the ORF1/2 junction region. During the four-year period, norovirus prevalence was 37.2%, varying from 20.1% in 2020 to 55.4% in 2021. GII genotypes dominated, being detected in 92.9% of samples. GII-infected patients had significantly higher viral concentrations compared to GI-infected patients (median of 3.8 × 10
GC/g and 6.7 × 10
GC/g, respectively); and patients aged >12-24 months showed a higher median viral load (8 × 10
GC/g) compared to other age groups. Norovirus sequencing revealed 20 genotypes by phylogenetic analysis of RdRp and VP1 partial regions. GII.4 SydneyP16 was the dominant genotype (57.3%), especially in 2019 and 2021, followed by GII.2P16 (14.8%) and GII.6P7 (6.3%). The intergenogroup recombinant genotype, GIX.1GII.P15, was detected in five samples. Our study is the first to explore norovirus epidemiology and genotype distribution in Brazil during COVID-19, and contributes to understanding the epidemiological dynamics of norovirus and highlighting the importance of continuing to follow norovirus surveillance programs in Brazil.
This 15-year study aimed to determine the role of the main viruses responsible for acute infantile gastroenteritis cases in a day care center in the city of Rio de Janeiro, Brazil. From 1994 to 2008, ...539 fecal samples were obtained from 23 outbreaks as well as sporadic cases that occurred in this period. The detection of Rotavirus group A (RVA), norovirus (NoV) and astrovirus (AstV) was investigated both by classical and molecular methods of viral detection. RVA was detected by enzymatic immune assay and/or polyacrylamide gel electrophoresis and genotyped by using semi-nested multiplex PCR. NoV and AstV were subsequently tested by real time PCR in all RVA-negative samples and genotyped throughout genome sequencing. Three protocols for molecular characterization of NoV nucleotide sequencing were performed with the partial nucleotide sequencing of genomic regions known as region B (polymerase gen), C and D (capsid gen).Viruses were identified in 47.7% (257/539) of the cases, and the detection rates of RVA, NoV and AstV in16.1% (87/539), 33.4% (151/452), and 6.3% (19/301), respectively. Most gastroenteritis cases were reported in autumn and winter, although NoV presented a broader monthly distribution. Viruses' detection rates were significantly higher among children aged less than 24 months old, although NoV cases were detected in all age groups. RVA genotypes as G1P8, G9P8, G2P4, G3P8 and G1+G3P8 and RVA was no longer detected after 2005. NoV characterization revealed genotypes variability circulating in the period as GI.2, GI.3, GI.8 GII.2, GII.3, GII.4, GII.4 variants 2001 and 2006b, GII.6, GII.7, GII.12 and GII.17. AstV genotypes 1, 2, 4 and 5 were also characterized. Those data demonstrate the impact of NoV infection in cases of infantile gastroenteritis, surpassing RVA infection responsible for high morbidity rate in children under five years old.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Rotavirus specie A (RVA) infection is the leading cause of severe acute diarrhea among young children worldwide. To reduce this major RVA health impact, the Rotarix
® vaccine (GlaxoSmithKline, ...Rixensart, Belgium) was introduced in the Brazilian Expanded Immunization Program in March 2006 and became available to the entire birth cohort. The aim of this study was to evaluate the spread of RVA in the environment after the introduction of Rotarix
® in Brazil. For this purpose, a Wastewater Treatment Plant (WTP) in Rio de Janeiro was monitored for one year to detect, characterize and discriminate RVA genotypes and identify possible circulation of vaccine strains. Using TaqMan
® quantitative PCR (qPCR), RVA was detected in 100% (mean viral loads from 2.40
×
10
5 to 1.16
×
10
7 genome copies (GC)/L) of sewage influent samples and 71% (mean viral loads from 1.35
×
10
3 to 1.64
×
10
5
GC/L) of sewage effluent samples. The most prevalent RVA genotypes were P4, P6 and G2, based on VP4 and VP7 classification. Direct nucleotide sequencing (NSP4 fragment) and restriction enzyme digestion (NSP3) analysis did not detect RVA vaccine-like strains from the sewage samples. These data on RVA detection, quantification and molecular characterization highlight the importance of environmental monitoring as a tool to study RVA epidemiology in the surrounding human population and may be useful on ongoing vaccine monitoring programs, since sewage may be a good screening option for a rapid and economical overview of the circulating genotypes.
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► Rotavirus A was detected in sewage samples during a year. ► Rotavirus temporal distribution and genotypes were examined. ► Two methodologies were applied to discriminate between rotavirus wild and vaccine strains.
Norovirus is a major cause of foodborne-associated acute gastroenteritis (AGE) outbreaks worldwide. Usually, food products are contaminated either during harvesting or preparation, and the most ...common products associated to norovirus outbreaks are raw or undercooked bivalve shellfish, fruits (frozen berries) and ready-to-eat produce. In the present study, we investigated an AGE outbreak caused by norovirus associated with the consumption of ice pops in southern Brazil. Clinical stool samples from patients and ice pops samples were collected and analyzed for viruses’ detection. By using RT-qPCR and sequencing, we detected the uncommon genotype GII.12P16 in clinical samples and GII.12 in samples of ice pop. Strains shared identity of 100% at nucleotide level strongly suggesting the consumption of ice pops as the source of the outbreak.
This study aimed to assess two homogenization methods to recover norovirus from Minas artisanal cheese (MAC) made with raw bovine milk obtained from four microregions of the Minas Gerais state, ...Brazil, with different ripening times and geographical and abiotic characteristics. For this purpose, 33 fiscal samples were artificially contaminated with norovirus GI and GII, and Mengovirus (MgV), used as an internal process control (IPC). TRIzol
®
reagent and Proteinase K homogenization methods were evaluated for all samples were then subjected to RNA extraction using viral magnetic beads and RT-qPCR Taqman
®
for viral detection/quantification. Proteinase K method showed better efficiency results for both norovirus GI and GII, with means recovery efficiency of 45.7% (95% CI 34.3–57.2%) and 41.4% (95% CI 29.1–53.6%), respectively, when compared to TRIzol method (16.6% GI, 95% CI 8.4–24.9%, and 12.3% GII, 95% CI 7.0–17.6%). The limits of detection for norovirus GI and GII for this method were 10
1
GC/g and 10
3
GC/g, respectively, independent of cheese origin. MgV was detected and revealed in 100% success rate in all types of cheese, with mean recovery efficiency of 25.6% for Proteinase K, and 3.8% for the TRIzol method. According to cheese origin, Triangulo Mineiro MAC had the highest mean recovery rates for the three viral targets surveyed (89% GI, 87% GII, and 51% MgV), while Serro MAC showed the lowest rates (
p
< 0.001). Those results indicate that the proteinase K adapted method is suitable for norovirus GI and GII detection in MAC and corroborated MgV as an applicable IPC to be used during the process.
Norovirus (NoV) is a major cause of acute gastroenteritis (AGE) worldwide, especially in children under five years. Studies involving the detection and molecular characterisation of NoV have been ...performed in Brazil, demonstrating its importance as an etiological agent of AGE.
The objectives of this study were to investigate the frequency of human NoV and to genotype the strains isolated from 0-14-year-old patients of AGE in Manaus, Brazil, over a period of two years.
A total of 426 faecal samples were collected between January 2010 and December 2011. All samples were tested for the presence of NoV antigens using a commercial enzyme immunoassay kit. RNA was extracted from all faecal suspensions and reverse transcription-polymerase chain reaction (RT-PCR) for the NoV-polymerase partial region was performed as a trial test. Positive samples were then subjected to PCR with specific primers for partial capsid genes, which were then sequenced.
NoV was detected in 150 (35.2%) faecal samples, for at least one of the two techniques used. NoV was detected in children from all age groups, with the highest positivity observed among the group of 1-2 years old. Clinically, fever was verified in 43% of the positive cases and 46.3% of the negative cases, and vomiting was observed in 75.8% and 70.8% cases in these groups, respectively. Monthly distribution showed that the highest positivity was observed in January 2010 (81.2%), followed by February and April 2010 and March 2011, when the positivity rate reached almost 50%. Phylogenetic analyses performed with 65 positive strains demonstrated that 58 (89.2%) cases of NoV belonged to genotype GII.4, five (7.7%) to GII.6, and one (1.5%) each to GII.7 and GII.3.
This research revealed a high circulation of NoV GII.4 in Manaus and contributed to the understanding of the importance of this virus in the aetiology of AGE cases, especially in a region with such few studies available.
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