Menira Souza

Adenovirus, calicivirus and astrovirus detection in fecal samples of hospitalized children with acute gastroenteritis from Campo Grande, MS, Brazil

We analyzed fecal samples from hospitalized children up to three years of age with acute gastroenteritis at Campo Grande, Mato Grosso do Sul, Brazil, from May 2000-January 2004. Astrovirus and calicivirus were detected by Reverse Transcription-Polymerase Chain Reaction and adenovirus was detected using the Rotavirus and Adenovirus combined immunoenzyme assay. Astrovirus, adenovirus and calicivirus were detected at rates of 3.1%, 3.6% and 7.6%, respectively. These results re-emphasize the need for the establishment of regional vigilance systems to evaluate the impact of enteric viruses on viral gastroenteritis.

Epidemiological features of rotavirus infection in Goiânia, Goiás, Brazil, from 1986 to 2000

A total of 2,605 faecal specimens from children up to 10 years old with or without diarrhoea were collected. Samples were obtained from 1986 to 2000 in hospitals, outpatient clinics and day-care centers in Goiânia, Goiás. Two methodologies for viral detection were utilized: a combined enzyme immunoassay for rotavirus and adenovirus and polyacrylamide gel electrophoresis. Results showed 374 (14.4%) faecal specimens positive for Rotavirus A, most of them collected from hospitalized children. A significant detection rate of rotavirus during the period from April to August, dry season in Goiânia, and different frequencies of viral detection throughout the years of study were also observed. Rotavirus was significantly related to hospitalization and to diarrhoeal illness in children up to 24 months old. This study reinforces the importance of rotavirus as a cause of diarrhoea in children and may be important in regards to the implementation of rotavirus vaccination strategies in our country.

Rotavirus A infections and reinfections: genotyping and vaccine implications.

OBJETIVOS: Identificar Rotavirus A em criancas com diarreia aguda, determinando os genotipos G e P prevalentes e avaliar a ocorrencia de infeccoes e reinfeccoes por rotavirus do grupo A em criancas. METODOS: Foram estudadas, prospectivamente, criancas com doenca diarreica aguda e identificacao de Rotavirus A em Goiânia (GO), durante o periodo de julho de 2000 a outubro de 2002. Igual numero de criancas, pareadas por idade e sexo, que nao apresentavam diarreia aguda e sem identificacao de rotavirus nas amostras fecais a admissao ao estudo, representou o grupo controle. Foram analisadas a ocorrencia de infeccoes ou reinfeccoes sintomaticas ou assintomaticas por rotavirus durante o periodo de estudo, durante um ano de seguimento em ambos os grupos. Todas as amostras positivas foram submetidas a genotipagem G e P atraves das reacoes de RT-PCR e Nested PCR. RESULTADOS: A infeccao por rotavirus ocorreu em 37,2% (77 de 207 amostras fecais) das criancas com diarreia aguda durante o periodo do estudo. Os genotipos G e P identificados foram, simultaneamente: G1 (62,3%), G9 (34,4%) e G4 (3,3%) e P[8] (59%), P[6] (7,7%), P[6]+P[8] (23,1%), P[4]+P[8] (7,7%) e P[4]+P[6] (2,6%). As associacoes de genotipos G e P identificados durante o estudo foram: G1P[8] (77,8%), G9P[8] (11,1%), G4P[8] (5,6%) e G1P[6] (5,6%). Nao houve reinfeccao por rotavirus nos pacientes do grupo Rotavirus A (+) durante o periodo de seguimento, enquanto duas criancas do grupo controle apresentaram infeccoes sintomaticas por rotavirus durante o mesmo periodo. CONCLUSOES: Os genotipos G e P predominantes correspondem aos das candidatas atuais a vacina contra rotavirus. Nao houve reinfeccao por rotavirus pelo periodo de um ano em relacao a todos os genotipos identificados.

Molecular and Serological Characterization of Group A Rotavirus Isolates Obtained from Hospitalized Children in Goiânia, Brazil, 1998–2000

Fecal samples positive for rotavirus group A (n=120) were analyzed by enzyme immunoassay-monoclonal antibody (EIA-MAb) serotyping and/or reverse transcription/multiplex polymerase chain reaction (PCR) amplification to determine the prevalence of the [P] and G genotypes. The most prevalent G genotype/serotype detected was G1 (76.7%), followed by G2 (5.0%). Six samples were characterized as G9 by multiplex PCR, and one sample was characterized as G3 by EIA-MAb. The combinations of [P] and G genotypes found were P[8] and G1 (20.8%), P[6] and G1 (10.8%), P[6] and G9 (4.2%), P[8] and G2 (1.7%), and P[6] and G2 (0.8%). The diversity of rotavirus group A [P] and G genotypes/serotypes reinforces the need for continuous characterization of rotaviruses circulating in populations in Brazil.

Prospective study on Norovirus infection among allogeneic stem cell transplant recipients: prolonged viral excretion and viral RNA in the blood.

BACKGROUND Human caliciviruses (Norovirus and Sapovirus) are important acute gastroenteritis agents. The Norovirus (NoV) disease is usually self-limited; however, prolonged viral excretion and complications have been reported, mainly in immunosuppressed individuals. OBJECTIVES In this prospective study, we have monitored allogeneic stem cell transplant (ASCT) patients for human calicivirus infection. STUDY DESIGN Ten ASCT patients were monitored for NoV and sapoviruses (SaV) infection, for a period of five months to a maximum of one year. Prolonged NoV excretion and long term viral RNA in the blood were assessed by multiplex RT-PCR targeting region C of the viral capsid. Secretor status of the patients was determined by enzyme immunoassay using Ulex Europaeus agglutinin. Partial genomic sequencing and phylogenetic analysis were performed to characterize the viral genotypes. RESULTS NoV was detected in six out of ten patients (60%). Prolonged viral excretion in feces (mean of 61.6 days) and long term presence of NoV RNA in the sera (mean of 33.6 days) of the patients were observed. SaV was not detected in any of the samples. All patients had diarrhea, vomiting and fever during NoV positivity. All NoV-positive samples were characterized as GI.3 NoV. Three Nov-infected patients presented with acute intestinal graft versus host disease. CONCLUSIONS This study brings important information on NoV course of infection in ASCT patients. It also provides evidence for long term viral RNA in the blood highlighting the importance of the inclusion of NoV screening in the routine testing performed before transplantation and during follow-up of these patients.

Monitoring the circulation of rotavirus among children after the introduction of the RotarixTM vaccine in Goiânia, Brazil

The epidemiological features of rotavirus A (RVA) infection differ between children from developing and developed countries which could result in differences in vaccine efficacy around the world. To evaluate the impact of Rotarix™ on RVA prevalence, we monitored RVA genotypes circulating in Goiânia by monitoring virus in faecal samples from children that had or had not been previously vaccinated. From February-November of 2008, 220 faecal samples were collected from children in seven day-care centres. RVA detection was performed by two methodologies and the results were confirmed by polyacrylamide gel electrophoresis. From the 220 samples, eight were RVA-positive (3.6%) and five were from children that had received either one or two doses of the vaccine. All positive samples were collected from children with diarrhoea during August and September. Genotyping of the RVA characterised five of the viral samples as genotype G2P[4] and one as G8P[4], suggesting that G2P[4] was the predominant circulating genotype in Goiânia during the study. The fact that vaccinated children were also infected by RVA suggests that the vaccine does not fully protect against infection by the G2[P4] RVA genotype.

Monitoring of Calicivirus among day-care children: Evidence of asymptomatic viral excretion and first report of GI.7 norovirus and GI.3 sapovirus in Brazil

Caliciviruses (Norovirus and Sapovirus) are important causes of acute gastroenteritis, with Norovirus (NoV) considered the leading cause of epidemic non‐bacterial acute gastroenteritis; however, molecular and epidemiological data of the circulating Calicivirus (CV) strains among day‐care children are still considered scarce. The role of asymptomatic CV excretion on viral transmission also remains poorly understood. The aim of the present study was to monitor the occurrence of NoV and Sapovirus (SaV) in a day‐care center and to describe the molecular epidemiology of the circulating strains. Genomic sequencing and phylogenetic analysis of the capsid region were carried out in CV positive samples obtained from children younger than 5 years, with or without diarrhea, between October 2009 and October 2011. A total of 539 fecal samples were screened for CV. Forty‐three (8%) were positive for NoV and 25 (4.6%) for SaV. Surprisingly, positivity rates for CV were significant in asymptomatic children, and virus circulation was detected in every month of the study. Great genomic diversity of CV was observed, and the circulating NoV strains were: GII.6, GII.2, GII.1, GI.7, GII.4, and GI.1. The SaV genotypes GI.1 and GI.3 were also detected. Five CV outbreaks caused by distinct viral strains were documented. This study provides an insight on the genetic diversity of CV in a day‐care in Central West Brazil, highlighting the probable role of asymptomatic viral excretion and the significance of semi‐closed settings in the dissemination of these agents. J. Med. Virol. 86:1569–1575, 2014.

Phylodynamics of DENV-1 reveals the spatiotemporal co-circulation of two distinct lineages in 2013 and multiple introductions of dengue virus in Goiás, Brazil.

Dengue virus type 1 (DENV-1) was the first serotype introduced in Brazil, during in the 1980s. Since then, this virus has spread in the Brazilian territory, causing several outbreaks. In 2013 the highest number of dengue cases was notified, when compared to the previous years in Brazil, and the state of Goiás reported over 160 thousand cases. In this study, we aimed to present the Phylodynamics of DENV-1 isolates from the state of Goiás, Brazil, during 2013 outbreak, based on the envelope gene (E) sequences. Phylogenetic analysis revealed that Brazilian DENV-1 isolates are grouped together with viruses from genotype V in two distinct lineages (lineage I and lineage II) reflecting co-circulation. Phylogeographic analyses showed that these lineages were introduced in different moments in Goiás, Brazil, using distinct routes, likely originated from the Caribbean. Lineage I was first introduced coming from Rio de Janeiro (2007-2012), followed by the introduction from Argentina (2010-2013). Lineage II was introduced in a single moment from Rio de Janeiro and this clade has existed since 2007-2010. The different viral introduction events demonstrate the viral dispersion process with neighboring regions, which is essential for the maintenance of outbreaks and introduction of new emerging viruses. In conclusion, obtained data reveals the importance of continuous molecular surveillance of this virus in different regions, providing a better understanding of DENV-1 circulation, considering the evolutionary and virus spread patterns.

Human bocavirus 1 and 3 infection in children with acute gastroenteritis in Brazil

To determine the positivity rate of human bocavirus (HBoV) 1 and 3 among children who presented with acute gastroenteritis symptoms during the period of 1994-2004 in the Central-West Region of Brazil, 762 faecal samples were tested using polymerase chain reaction (PCR) for the detection of HBoV DNA. Primers for a segment of the non-structural viral protein 1 (NS1) gene of HBoV-1 and HBoV-3 were used. Twelve HBoV-positive samples were further characterised via genomic sequencing and phylogenetic analysis. Of the samples tested, 5.8% (n = 44) were positive for HBoV-1 or HBoV-3 and co-infection was observed in 14 (31.8%) of the 44 HBoV-positive samples. Nine of the 14 samples were also positive for Rotavirus A and five were positive for Aichi virus. The genomic sequencing of the NS1 partial sequence of 12 HBoV-samples showed that 11 samples were characterised as HBoV-1 and that one was characterised as HBoV-3. The phylogenetic analysis showed that the HBoV-1 samples had a high sequence homology to others previously identified in China, Sweden and Brazil. This is the first study conducted in the Central-West Region of Brazil to detect HBoV-1 and HBoV-3 in faecal samples from children with acute gastroenteritis. Further studies are required to define the role of HBoVs as aetiological agents of gastroenteritis.

Detection of antibodies to Oropouche virus in non-human primates in Goiânia City, Goiás

INTRODUCTION Arboviruses are associated with human disease, and non-human primates (NHPs) are important primary hosts. This study shows the detection of antibodies to Oropouche virus (OROV) in NHPs either living in urban parks or acclimatized at the Wild Animal Screening Center, Goiânia city. METHODS Fifty blood samples were analyzed by hemagglutination-inhibition and neutralization assays. RESULTS Two monkeys (Alouatta caraya) had antibodies to OROV by both techniques. CONCLUSIONS This is the first report demonstrating the detection of OROV antibodies in Goiás State and may represent the introduction/circulation of OROV in the region and a potential risk to the human population.