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1.
Viruses ; 16(3)2024 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-38543776

RESUMO

Rotaviruses are a significant cause of severe, potentially life-threatening gastroenteritis in infants and the young of many economically important animals. Although vaccines against porcine rotavirus exist, both live oral and inactivated, their effectiveness in preventing gastroenteritis is less than ideal. Thus, there is a need for the development of new generations of porcine rotavirus vaccines. The Ohio State University (OSU) rotavirus strain represents a Rotavirus A species with a G5P[7] genotype, the genotype most frequently associated with rotavirus disease in piglets. Using complete genome sequences that were determined via Nanopore sequencing, we developed a robust reverse genetics system enabling the recovery of recombinant (r)OSU rotavirus. Although rOSU grew to high titers (~107 plaque-forming units/mL), its growth kinetics were modestly decreased in comparison to the laboratory-adapted OSU virus. The reverse genetics system was used to generate the rOSU rotavirus, which served as an expression vector for a foreign protein. Specifically, by engineering a fused NSP3-2A-UnaG open reading frame into the segment 7 RNA, we produced a genetically stable rOSU virus that expressed the fluorescent UnaG protein as a functional separate product. Together, these findings raise the possibility of producing improved live oral porcine rotavirus vaccines through reverse-genetics-based modification or combination porcine rotavirus vaccines that can express neutralizing antigens for other porcine enteric diseases.


Assuntos
Gastroenterite , Infecções por Rotavirus , Vacinas contra Rotavirus , Rotavirus , Humanos , Animais , Suínos , Genética Reversa , Ohio , Universidades , Infecções por Rotavirus/prevenção & controle , Infecções por Rotavirus/veterinária , Gastroenterite/prevenção & controle , Gastroenterite/veterinária
2.
Methods Mol Biol ; 2733: 249-263, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38064037

RESUMO

Rotaviruses are the primary cause of severe gastroenteritis in infants and young children throughout the world. To combat rotavirus illness, several live oral vaccines have been developed, or are under development, that are formulated from attenuated human or human-animal reassortant strains of rotavirus. While the effectiveness of these vaccines is generally high in developed countries, the same vaccines are significantly less effective in many developing countries, where the need for rotavirus vaccines is greatest. Recently, reverse genetics systems have been developed that allow modification of the segmented double-stranded (ds)RNA genome of rotavirus, including reprogramming the genome to allow expression of additional proteins that may stimulate expanded neutralizing antibody responses in vaccinated children. The use of reverse genetics systems may not only lead to the development of more potent classes of vaccines but can be used to better explore the intricacies of rotavirus molecular biology and pathogenesis. In this article, we share protocols that can be used to generate recombinant rotaviruses, including modified strains that express foreign proteins.


Assuntos
Gastroenterite , Infecções por Rotavirus , Rotavirus , Vacinas , Lactente , Animais , Criança , Humanos , Pré-Escolar , Rotavirus/genética , Genética Reversa/métodos
3.
mBio ; : e0225523, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37905816

RESUMO

The binding of viral RNA to RIG-I-like receptors triggers the formation of mitochondrial antiviral signaling (MAVS) protein aggregates critical for interferon (IFN) expression. Several rotavirus strains have been shown to suppress IFN expression by inducing MAVS degradation. Relying on transient expression assays, previous studies reached different conclusions regarding the identity of the rotavirus protein responsible for MAVS degradation, suggesting it was an activity of the rotavirus capping enzyme VP3 or the interferon antagonist NSP1. Here, we have used recombinant SA11 rotaviruses to identify the endogenous viral protein responsible for MAVS degradation and to analyze how the attack on MAVS impacts IFN expression. The recombinant viruses included those expressing modified VP3 or NSP1 proteins deficient in the ability to induce the degradation of MAVS or interferon regulatory factor-3 (IRF3), or both. With these viruses, we determined that VP3 directs the proteasomal degradation of MAVS but plays no role in IRF3 degradation. Moreover, NSP1 was determined to induce IRF3 degradation but to have no impact on MAVS degradation. Analysis of rotavirus-infected cells indicated that IRF3 degradation was more efficient than MAVS degradation and that NSP1 was primarily responsible for suppressing IFN expression in infected cells. However, VP3-mediated MAVS degradation contributed to IFN suppression in cells that failed to produce functional NSP1, pointing to a subsidiary role for VP3 in the IFN antagonist activity of NSP1. Thus, VP3 is a multifunctional protein with several activities that counter anti-rotavirus innate immune responses, including capping of viral (+)RNAs, hydrolysis of the RNase L 2-5A (2'-5' oligoadenylate) signaling molecule, and proteasomal degradation of MAVS. IMPORTANCE Rotavirus is an enteric RNA virus that causes severe dehydrating gastroenteritis in infants and young children through infection of enterocytes in the small intestine. Timely clearance of the virus demands a robust innate immune response by cells associated with the small intestine, including the expression of interferon (IFN). Previous studies have shown that some rotavirus strains suppress the production of interferon, by inducing the degradation of mitochondrial antiviral signaling (MAVS) protein and interferon regulatory factor-3 (IRF3). In this study, we have used reverse genetics to generate recombinant rotaviruses expressing compromised forms of VP3 or NSP1, or both, to explore the function of these viral proteins in the degradation of MAVS and IRF3. Our results demonstrate that VP3 is responsible for MAVS depletion in rotavirus-infected cells, and through this activity, helps to suppress IFN production. Thus, VP3 functions to support the activity of rotavirus NSP1, the major interferon antagonist of the virus.

4.
Microbiol Resour Announc ; 12(11): e0060323, 2023 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-37819123

RESUMO

The live oral rotavirus RV1 (Rotarix) vaccine is formulated from the human G1P[8] RIX4414 virus. Based on RIX4414 sequences, T7 expression plasmids were constructed that supported recovery of recombinant RIX4414-like viruses by reverse genetics. These plasmids will advance the study of the RV1 vaccine, possibly allowing improvements to its efficacy.

5.
Viruses ; 15(9)2023 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-37766270

RESUMO

Human rotavirus (HRV) is a leading cause of viral gastroenteritis in children across the globe. The virus has long been established as a pathogen of the gastrointestinal tract, targeting small intestine epithelial cells and leading to diarrhea, nausea, and vomiting. Recently, this classical infection pathway was challenged by the findings that murine strains of rotavirus can infect the salivary glands of pups and dams and transmit via saliva from pups to dams during suckling. Here, we aimed to determine if HRV was also capable of infecting salivary glands and spreading in saliva using a gnotobiotic (Gn) pig model of HRV infection and disease. Gn pigs were orally inoculated with various strains of HRV, and virus shedding was monitored for several days post-inoculation. HRV was shed nasally and in feces in all inoculated pigs. Infectious HRV was detected in the saliva of four piglets. Structural and non-structural HRV proteins, as well as the HRV genome, were detected in the intestinal and facial tissues of inoculated pigs. The pigs developed high IgM antibody responses in serum and small intestinal contents at 10 days post-inoculation. Additionally, inoculated pigs had HRV-specific IgM antibody-secreting cells present in the ileum, tonsils, and facial lymphoid tissues. Taken together, these findings indicate that HRV can replicate in salivary tissues and prime immune responses in both intestinal and facial lymphoid tissues of Gn pigs.


Assuntos
Infecções por Rotavirus , Rotavirus , Criança , Animais , Humanos , Suínos , Camundongos , Tecido Linfoide , Proteínas , Imunoglobulina M , Imunidade , Vida Livre de Germes , Glândulas Salivares
6.
Viruses ; 12(11)2020 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-33217894

RESUMO

Understanding the epidemiology of human norovirus infection in children within Ghana and the entire sub-Saharan African region, where future norovirus vaccines would have the greatest impact, is essential. We analyzed 1337 diarrheic stool samples collected from children <5 years from January 2008 to December 2017 and found 485 (36.2%) shedding the virus. GII.4 (54.1%), GII.3 (7.7%), GII.6 (5.3%), GII.17 (4.7%), and GII.5 (4.7%) were the most common norovirus genotypes. Although norovirus GII.4 remained the predominant capsid genotype throughout the study period, an increase in GII.6 and GII.3 capsid genotypes was observed in 2013 and 2014, respectively. The severity of clinical illness in children infected with GII.4 norovirus strains was similar to illness caused by non-GII.4 strains. Since the epidemiology of norovirus changes rapidly, establishment of systematic surveillance within sentinel sites across the country would enhance the monitoring of circulating norovirus strains and allow continuous understanding of norovirus infection in Ghana.


Assuntos
Infecções por Caliciviridae/epidemiologia , Gastroenterite/epidemiologia , Genótipo , Norovirus/genética , Infecções por Caliciviridae/diagnóstico , Pré-Escolar , Fezes/virologia , Feminino , Gastroenterite/virologia , Variação Genética , Gana/epidemiologia , Humanos , Lactente , Recém-Nascido , Masculino , Norovirus/classificação , Filogenia , Prevalência , Análise de Sequência de DNA , Eliminação de Partículas Virais
7.
Arch Virol ; 165(4): 1003-1005, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32037490

RESUMO

We previously reported the VP4 and the VP7 genotypes of the first G6P[14] rotavirus strain (RVA/Human-wt/GHA/M0084/2010/G6P[14]) from the stool of an infant with diarrhoea in Ghana. In the current study, we obtained the complete genome sequences using Illumina MiSeq next-generation sequencing to enable us to determine the host species origin of the genes by phylogenetic analysis. The genotype constellation was G6-P[14]-I2-R2-C2-M2-A11-N2-T6-E2-H3. Phylogenetic analysis showed that M0084 was a reassortant strain from RVAs of both artiodactyl and human host species origin. The level of sequence identity of the individual genes of M0084 to other sequences in the GenBank ranged from 95.2 to 99.5%; however, there was no single strain from the GenBank database with a complete genome sequence that was highly similar to that of M0084. To help trace the source of such unique gene pools being introduced into human RVAs, it will be useful to examine RVA sequences from potential reservoirs such as sheep and goats, which are common domestic animals in this locality.


Assuntos
Diarreia/virologia , Doenças das Cabras/virologia , Vírus Reordenados/isolamento & purificação , Infecções por Rotavirus/veterinária , Infecções por Rotavirus/virologia , Rotavirus/isolamento & purificação , Doenças dos Ovinos/virologia , Animais , Diarreia/terapia , Fezes/virologia , Genoma Viral , Gana , Cabras , Sequenciamento de Nucleotídeos em Larga Escala , Hospitalização , Humanos , Lactente , Filogenia , Vírus Reordenados/classificação , Vírus Reordenados/genética , Rotavirus/classificação , Rotavirus/genética , Infecções por Rotavirus/terapia , Ovinos
8.
PLoS One ; 14(6): e0218348, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31199823

RESUMO

In 2010, the rare OP354-like P[8]b rotavirus subtype was detected in children less than 2 years old in Ghana. In this follow-up study, to provide insight into the evolutionary history of the genome of Ghanaian P[8]b strains RVA/Human-wt/GHA/GHDC949/2010/G9P[8] and RVA/Human-wt/GHA/GHM0094/2010/G9P[8] detected in an infant and a 7-month old child hospitalised for acute gastroenteritis, we sequenced the complete genome using both Sanger sequencing and Illumina MiSeq technology followed by phylogenetic analysis of the near-full length sequences. Both strains possessed the Wa-like/genotype 1 constellation G9P[8]b-I1-R1-C1-M1-A1-N1-T1-E1-H1. Sequence comparison and phylogenetic inference showed that both strains were identical at the lineage level throughout the 11 genome segments. Their VP7 sequences belonged to the major sub-lineage of the G9-lineage III whereas their VP4 sequences belonged to P[8]b cluster I. The VP7 and VP4 genes of the study strains were closely related to a Senegalese G9P[8]b strain detected in 2009. In the remaining nine genome segments, both strains consistently clustered together with Wa-like RVA strains possessing either P[8]a or P[8]b mostly of African RVA origin. The introduction of a P[8]b subtype VP4 gene into the stable Wa-like strain backbone may result in strains that might propagate easily in the human population, with a potential to become an important public health concern, especially because it is not certain if the monovalent rotavirus vaccine (Rotarix) used in Ghana will be efficacious against such strains. Our analysis of the full genomes of GHM0094 and GHDC949 adds to knowledge of the genetic make-up and evolutionary dynamics of P[8]b rotavirus strains.


Assuntos
Diarreia/virologia , Evolução Molecular , Genoma Viral , Genômica , Infecções por Rotavirus/virologia , Rotavirus/classificação , Rotavirus/genética , Variação Genética , Genômica/métodos , Genótipo , Gana , Humanos , Filogenia , Rotavirus/isolamento & purificação , Sequenciamento Completo do Genoma
9.
PLoS One ; 14(6): e0218790, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31242245

RESUMO

The World Health Organisation rotavirus surveillance networks have documented and shown eclectic geographic and temporal diversity in circulating G- and P- genotypes identified in children <5 years of age. To effectively monitor vaccine performance and effectiveness, robust molecular and phylogenetic techniques are essential to detect novel strain variants that might emerge due to vaccine pressure. This study inferred the phylogenetic history of the VP7 and VP4 genes of previously non-typeable strains and provided insight into the diversity of P[8] VP4 sequences which impacted the outcome of our routine VP4 genotyping method. Near-full-length VP7 gene and the VP8* fragment of the VP4 gene were obtained by Sanger sequencing and genotypes were determined using RotaC v2.0 web-based genotyping tool. The genotypes of the 57 rotavirus-positive samples with sufficient stool was determined. Forty-eight of the 57 (84.2%) had the P[8] specificity, of which 43 (89.6%) were characterized as P[8]a subtype and 5 (10.4%) as the rare OP354-like subtype. The VP7 gene of 27 samples were successfully sequenced and their G-genotypes confirmed as G1 (18/27) and G9 (9/27). Phylogenetic analysis of the P[8]a sequences placed them in subcluster IIIc within lineage III together with contemporary G1P[8], G3P[8], G8P[8], and G9P[8] strains detected globally from 2006-2016. The G1 VP7 sequences of the study strains formed a monophyletic cluster with African G1P[8] strains, previously detected in Ghana and Mali during the RotaTeq vaccine trial as well as Togo. The G9 VP7 sequences of the study strains formed a monophyletic cluster with contemporary African G9 sequences from neighbouring Burkina Faso within the major sub-cluster of lineage III. Mutations identified in the primer binding region of the VP8* sequence of the Ghanaian P[8]a strains may have resulted in the genotyping failure since the newly designed primer successfully genotyped the previously non-typeable P[8] strains. In summary, the G1, G9, and P[8]a sequences were highly similar to contemporary African strains at the lineage level. The study also resolved the methodological challenges of the standard genotyping techniques and highlighted the need for regular evaluation of the multiplex PCR-typing method especially in the post-vaccination era. The study further highlights the need for regions to start using sequencing data from local rotavirus strains to design and update genotyping primers.


Assuntos
Proteínas do Capsídeo/genética , Infecções por Rotavirus/virologia , Rotavirus/genética , Antígenos Virais/genética , Pré-Escolar , Genótipo , Gana/epidemiologia , Humanos , Lactente , Epidemiologia Molecular , Filogenia , Polimorfismo Genético , RNA Viral/genética , Rotavirus/classificação , Infecções por Rotavirus/epidemiologia
10.
PLoS One ; 14(5): e0217422, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31150425

RESUMO

Recent increase in the detection of unusual G1P[8], G3P[8], G8P[8], and G9P[4] Rotavirus A (RVA) strains bearing the DS-1-like constellation of the non-G, non-P genes (hereafter referred to as the genotype 2 backbone) requires better understanding of their evolutionary relationship. However, within a genotype, there is lack of a consensus lineage designation framework and a set of common sequences that can serve as references. Phylogenetic analyses were carried out on over 8,500 RVA genotype 2 genes systematically retrieved from the rotavirus database within the NCBI Virus Variation Resource. In line with previous designations, using pairwise comparison of cogent nucleotide sequences and stringent bootstrap support, reference lineages were defined. This study proposes a lineage framework and provides a dataset ranging from 34 to 145 sequences for each genotype 2 gene for orderly lineage designation of global genotype 2 genes of RVAs detected in human and animals. The framework identified five to 31 lineages depending on the gene. The least number of lineages (five to seven) were observed in genotypes A2 (NSP1), T2 (NSP3) and H2 (NSP5) which are limited to human RVA whereas the most number of lineages (31) was observed in genotype E2 (NSP4). Sharing of the same lineage constellations of the genotype 2 backbone genes between recently-emerging, unusual G1P[8], G3P[8], G8P[8] and G9P[4] reassortants and many contemporary G2P[4] strains provided strong support to the hypothesis that unusual genotype 2 strains originated primarily from reassortment events in the recent past involving contemporary G2P[4] strains as one parent and ordinary genotype 1 strains or animal RVA strains as the other. The lineage framework with selected reference sequences will help researchers to identify the lineage to which a given genotype 2 strain belongs, and trace the evolutionary history of common and unusual genotype 2 strains in circulation.


Assuntos
Evolução Molecular , Genes Virais/genética , RNA Viral/genética , Infecções por Rotavirus/virologia , Rotavirus/genética , Animais , Sequência de Bases/genética , Genótipo , Humanos , Filogenia , Infecções por Rotavirus/veterinária
11.
Infect Genet Evol ; 69: 246-254, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30763773

RESUMO

Rotavirus A (RVA) causes acute diarrhoea in children and less frequently in adults. However, the knowledge about the genotype distribution of RVA strains circulating in adults is limited particularly in developing countries. This study aimed to characterise the RVA strains detected from adult patients with diarrhoea in Nepal. A total of 47 RVA positive stool samples from adult patients with diarrhoea in Kathmandu, Nepal during 2007-2008 were examined for the G and P genotypes by sequencing. Nearly half (49%) of the samples were genotyped as G9P[8] (n = 23), G1P[8], G2P[4] (n = 5 each), G12P[8] (n = 4), G12P[6] (n = 3), G1P[6] (n = 2), G3P[8] and G9P[6] (n = 1 each). Interestingly, two G11P[25] and one G9P[19] strains detected were further subjected to Illumina MiSeq next generation sequencing to determine their whole genome sequences. The genotype constellations of RVA/Human-wt/NPL/TK2615/2008/G11P[25] and RVA/Human-wt/NPL/TK2620/2008/G11P[25] were I12-R1-C1-M1-A1-N1-T1-E1-H1, whereas that of RVA/Human-wt/NPL/TK1797/2007/G9P[19] was I5-R1-C1-M1-A8-N1-T1-E1-H1. The 11 genes of TK2615 and TK2620 were virtually identical, and they were either porcine-like or unique except the VP2 and NSP1 genes which were of human RVA origin. The two G11P[25] strains were also very similar to KTM368, another G11P[25] isolated from a child in Nepal in 2004. On the other hand, no gene of TK1797 was likely to be of human RVA origin. The observation that porcine-like RVAs were detected from adult patients justifies further studies to explore the role of adults in the interspecies transmission of animal RVA to humans.


Assuntos
Diarreia/epidemiologia , Diarreia/virologia , Genoma Viral , Infecções por Rotavirus/epidemiologia , Infecções por Rotavirus/virologia , Rotavirus/classificação , Rotavirus/genética , Antígenos Virais/genética , Antígenos Virais/imunologia , Genótipo , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Nepal/epidemiologia , Filogenia
12.
Pediatr Infect Dis J ; 37(11): 1172-1174, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30312266

RESUMO

We used the dideoxynucleotide chain termination method to determine the strains of nine non-typeable rotavirus enzyme immunoassay-positive samples, which were identified as G2. We detected nucleotide changes in the primer-binding region and amino acid substitutions within the VP7 protein of the G2 rotavirus strains. Genotyping primers need to be updated regularly.


Assuntos
Substituição de Aminoácidos , Antígenos Virais/genética , Proteínas do Capsídeo/genética , Rotavirus/genética , Fezes/virologia , Gastroenterite/virologia , Genótipo , Gana , Humanos , Filogenia , Reação em Cadeia da Polimerase , RNA Viral/genética , Infecções por Rotavirus , Análise de Sequência de DNA
13.
PLoS One ; 13(7): e0199304, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29969466

RESUMO

Exposure to fecal contamination in public areas, especially in dense, urban environments, may significantly contribute to enteric infection risk. This study examined associations between sanitation and fecal contamination in public environments in four low-income neighborhoods in Accra, Ghana. Soil (n = 72) and open drain (n = 90) samples were tested for E. coli, adenovirus, and norovirus. Sanitation facilities in surveyed households (n = 793) were categorized by onsite fecal sludge containment ("contained" vs. "uncontained") using previous Joint Monitoring Program infrastructure guidelines. Most sanitation facilities were shared by multiple households. Associations between spatial clustering of household sanitation coverage and fecal contamination were examined, controlling for neighborhood and population density (measured as enumeration areas in the 2010 census and spatially matched to sample locations). E. coli concentrations in drains within 50m of clusters of contained household sanitation were more than 3 log-units lower than those outside of clusters. Further, although results were not always statistically significant, E. coli concentrations in drains showed consistent trends with household sanitation coverage clusters: concentrations were lower in or near clusters of high coverage of household sanitation facilities-especially contained facilities-and vice versa. Virus detection in drains and E. coli concentrations in soil were not significantly associated with clustering of any type of household sanitation and did not exhibit consistent trends. Population density alone was not significantly associated with any of the fecal contamination outcomes by itself and was a significant, yet inconsistent, effect modifier of the association between sanitation clusters and E. coli concentrations. These findings suggest clustering of contained household sanitation, even when shared, may be associated with lower levels of fecal contamination within drains in the immediate public domain. Further research is needed to better quantify these relationships and examine impacts on health.


Assuntos
Monitoramento Ambiental , Poluição Ambiental/análise , Saneamento/estatística & dados numéricos , Esgotos/análise , Adenoviridae/isolamento & purificação , Análise por Conglomerados , Escherichia coli/isolamento & purificação , Fezes/microbiologia , Fezes/virologia , Gana , Humanos , Norovirus/isolamento & purificação , Densidade Demográfica , Pobreza/estatística & dados numéricos , Características de Residência , Eliminação de Resíduos Líquidos/economia , Eliminação de Resíduos Líquidos/métodos
14.
Arch Virol ; 163(8): 2257-2260, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29623434

RESUMO

Full genome sequencing of six feline Rotavirus A (RVA) strains isolated in Japan in the 1990s revealed three genotype constellations, one of which had a unique constellation of G3-P[3]-I3-R3-C3-M3-A15-N3-T3-E3-H6. Genotype A15, carried by RVA/Cat-tc/JPN/FRV348/1994/G3P[3], is a rare NSP1 genotype, and only one human and one canine RVA strains have thus far been reported to carry this genotype. The other three G3P[3] strains (FRV72, FRV73, and FRV303) possessed a constellation of I3-R3-C2-M3-A9-N2-T3-E3-H6, whereas two G3P[9] strains (FRV317 and FRV384) possessed a constellation of I3-R3-C3-M3-A3-N3-T3-E3-H3.


Assuntos
Doenças do Gato/virologia , Infecções por Rotavirus/veterinária , Animais , Gatos , Genoma Viral , Genótipo , Japão , Filogenia , Rotavirus/classificação , Rotavirus/genética , Rotavirus/isolamento & purificação , Infecções por Rotavirus/virologia , Proteínas Virais/genética
15.
Arch Virol ; 163(8): 2261-2263, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29623435

RESUMO

Animal rotavirus A (RVA) strains can infect children and cause diarrhoea. We determined the full genome sequences of one G3P[6] strain (NT0001) and five G4P[6] strains (NT0042, NT0077, NT0205, NT0599, and NT0621) detected from children with diarrhoea in Vietnam in 2007-2008. Strain NT0001 had a genotype constellation of: G3-P[6]-I5-R1-C1-M1-A8-N1-T1-E1-H1, strain NT0042: G4-P[6]-I1-R1-C1-M1-A8-N1-T1-E1-H1, strain NT0077: G4-P[6]-I5-R1-C1-M1-A8-N1-T7-E1-H1, and strains NT0205, NT0599, and NT0621: G4-P[6]-I1-R1-C1-M1-A1-N1-T1-E1-H1. Sequence divergence data and phylogenetic analysis showed that they were different porcine RVA strains that independently and directly crossed the host species barrier to infect children.


Assuntos
Diarreia/virologia , Infecções por Rotavirus/veterinária , Infecções por Rotavirus/virologia , Rotavirus/isolamento & purificação , Doenças dos Suínos/virologia , Animais , Fezes/virologia , Feminino , Genoma Viral , Genótipo , Humanos , Lactente , Masculino , Filogenia , Rotavirus/classificação , Rotavirus/genética , Suínos , Vietnã , Proteínas Virais/genética
16.
Am J Trop Med Hyg ; 98(5): 1250-1259, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29557327

RESUMO

In crowded urban settlements in low-income countries, many households rely on shared sanitation facilities. Shared facilities are not currently considered "improved sanitation" because of concerns about whether hygiene conditions sufficiently protect users from the feces of others. Prevention of fecal exposure at a latrine is only one aspect of sanitary safety. Ensuring consistent use of latrines for feces disposal, especially child feces, is required to reduce fecal contamination in households and communities. Household crowding and shared latrine access are correlated in these settings, rendering latrine use by neighbors sharing communal living areas as critically important for protecting one's own household. This study in Accra, Ghana, found that household access to a within-compound basic latrine was associated with higher latrine use by children of ages 5-12 years and for disposal of feces of children < 5 years, compared with households using public latrines. However, within-compound access was not associated with improved child feces disposal by other caregivers in the compound. Feces was rarely observed in household compounds but was observed more often in compounds with latrines versus compounds relying on public latrines. Escherichia coli and human adenovirus were detected frequently on household surfaces, but concentrations did not differ when compared by latrine access or usage practices. The differences in latrine use for households sharing within-compound versus public latrines in Accra suggest that disaggregated shared sanitation categories may be useful in monitoring global progress in sanitation coverage. However, compound access did not completely ensure that households were protected from feces and microbial contamination.


Assuntos
Pobreza , Banheiros/normas , Cuidadores , Características da Família , Fezes , Feminino , Gana , Humanos , Mães
17.
Arch Virol ; 163(3): 791-794, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29196818

RESUMO

Equine-like G3P[8] rotavirus A strains with DS-1-like backbone genes have emerged since 2013. An equine-like RVA/Human-wt/JPN/15R429/2015/G3P[8] strain possessing I2-R2-C2-M2-A2-N2-T2-E2-H2 was detected in Japan in 2015. Its VP7 gene was ≥ 99.3% identical to those of equine-like G3P[4] strains detected in Japan, and the remaining 10 genes were 98.6-99.8% identical to G1P[8] double-gene reassortants detected in Japan, Thailand and the Philippines. Thus, 15R429 was likely generated through reassortment between the equine-like G3P[4] and G1P[8] reassortant strains. Notably, 15R429 was 98.5-99.8% identical across all 11 genes of the equine-like G3P[8] strains detected in Spain and Hungary in 2015.


Assuntos
Antígenos Virais/genética , Proteínas do Capsídeo/genética , Gastroenterite/veterinária , Doenças dos Cavalos/epidemiologia , Filogenia , Vírus Reordenados/genética , Infecções por Rotavirus/veterinária , Rotavirus/genética , Sequência de Aminoácidos , Animais , Europa (Continente)/epidemiologia , Gastroenterite/epidemiologia , Gastroenterite/virologia , Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Doenças dos Cavalos/virologia , Cavalos/virologia , Humanos , Japão/epidemiologia , Vírus Reordenados/classificação , Vírus Reordenados/isolamento & purificação , Rotavirus/classificação , Rotavirus/isolamento & purificação , Infecções por Rotavirus/epidemiologia , Infecções por Rotavirus/virologia , Homologia de Sequência de Aminoácidos
18.
Genome Biol ; 18(1): 221, 2017 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-29141654

RESUMO

Open Science is encouraged by the European Union and many other political and scientific institutions. However, scientific practice is proving slow to change. We propose, as early career researchers, that it is our task to change scientific research into open scientific research and commit to Open Science principles.


Assuntos
Bases de Dados como Assunto , Pesquisadores , Ciência
19.
Microbiol Immunol ; 61(8): 328-336, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28696017

RESUMO

One major mechanism by which Rotavirus A (RVA) evolves is genetic reassortment between strains with different genotype constellations. However, the parental strains of the reassortants generated have seldom been identified. Here, the whole genome of two suspected reassortants, RVA/Human-wt/VNM/SP127/2013/G1P[4] and RVA/Human-wt/VNM/SP193/2013/G1P[4], with short RNA electropherotypes were examined by Illumina MiSeq sequencing and their ancestral phylogenies reconstructed. Their genotype constellation, G1-P[4]-I2-R2-C2-M2-A2-N2-T2-E2-H2, indicated that they were G1 VP7 mono-reassortants possessing DS-1-like genetic backbones. The two strains were ≧99.7% identical across the genome. While their VP7 genes were ≧99.7 identical to that of a Wa-like strain RVA/Human-wt/VNM/SP110/2012/G1P[8] which co-circulated during the 2012/2013 season, 10 genes were ≧99.8% identical to that of the DS-1-like strains RVA/Human-wt/VNM/SP015/2012/G2P[4] (and SP108) that co-circulated during the season. The identities were consistent with the phylogenetic relationships observed between the genes of the reassortants and those of the afore-mentioned strains. Consequently, the G1P[4] strains appear to have been generated by genetic reassortment between SP110-like and SP015-like strains. In conclusion, this study provides robust molecular evidence for the first time that G1P[4] strains detected in Hanoi Vietnam were generated by inter-genogroup reassortment between co-circulating G1P[8] and G2P[4] strains within the same place and season.


Assuntos
Genoma Viral/genética , RNA Viral/genética , Vírus Reordenados/genética , Recombinação Genética/genética , Rotavirus/genética , Antígenos Virais/genética , Proteínas do Capsídeo/genética , Variação Genética/genética , Genótipo , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Filogenia , Rotavirus/classificação , Análise de Sequência de RNA , Vietnã
20.
Infect Genet Evol ; 54: 164-169, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28673546

RESUMO

A rare G26 Rotavirus A strain RVA/Human-wt/NPL/07N1760/2007/G26P[19] was detected in a child hospitalised for acute diarrhoea in Kathmandu, Nepal. The complete genome of 07N1760 was determined in order to explore its evolutionary history as well as examine its relationship to a Vietnamese strain RVA/Human-wt/VNM/30378/2009/G26P[19], the only G26 strain whose complete genotype constellation is known. The genotype constellation of 07N1760 was G26-P[19]-I12-R1-C1-M1-A8-N1-T1-E1-H1, a unique constellation identical to that of the Vietnamese 30378 except the VP6 gene. Phylogenetic analysis revealed that both strains were unrelated at the lineage level despite their similar genotype constellation. The I12 VP6 gene of 07N1760 was highly divergent from the six currently deposited I12 sequences in the GenBank. Except for its NSP2 gene, the remaining genes of 07N1760 shared lineages with porcine and porcine-like human RVA genes. The NSP2 gene belonged to a human RVA N1 lineage which was distinct from typical porcine and porcine-like human lineages. In conclusion, the Nepali G26P[19] strain 07N1760 was a porcine RVA strain which derived an NSP2 gene from a human Wa-like RVA strain by intra-genotype reassortment probably after transmission to the human host.


Assuntos
Diarreia/virologia , Genoma Viral/genética , Vírus Reordenados/genética , Infecções por Rotavirus/virologia , Rotavirus/genética , Animais , Hospitalização , Humanos , Lactente , Masculino , Epidemiologia Molecular , Nepal , Filogenia , Análise de Sequência de RNA , Suínos , Doenças dos Suínos/virologia
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