Mirleide Cordeiro dos Santos

The Dilemma of Influenza Vaccine Recommendations when Applied to the Tropics: The Brazilian Case Examined Under Alternative Scenarios

Since 1999 the World Health Organization issues annually an additional influenza vaccine composition recommendation. This initiative aimed to extend to the Southern Hemisphere (SH) the benefits—previously enjoyed only by the Northern Hemisphere (NH)—of a vaccine recommendation issued as close as possible to the moment just before the onset of the influenza epidemic season. A short time between the issue of the recommendation and vaccine delivery is needed to maximize the chances of correct matching between putative circulating strains and one of the three strains present in the vaccine composition. Here we compare the effectiveness of the SH influenza vaccination adopted in Brazil with hypothetical alternative scenarios defined by different timings of vaccine delivery and/or composition. Scores were based on the temporal overlap between vaccine-induced protection and circulating strains. Viral data were obtained between 1999 and 2007 from constant surveillance and strain characterization in two Brazilian cities: Belém, located at the Equatorial region, and São Paulo, at the limit between the tropical and subtropical regions. Our results show that, among currently feasible options, the best strategy for Brazil would be to adopt the NH composition and timing, as in such case protection would increase from 30% to 65% (p<.01) if past data can be used as a prediction of the future. The influenza season starts in Brazil (and in the equator virtually ends) well before the SH winter, making the current delivery of the SH vaccination in April too late to be effective. Since Brazil encompasses a large area of the Southern Hemisphere, our results point to the possibility of these conclusions being similarly valid for other tropical regions.

Prevalence and clinical features of respiratory syncytial virus in children hospitalized for community-acquired pneumonia in northern Brazil

BackgroundChildhood pneumonia and bronchiolitis is a leading cause of illness and death in young children worldwide with Respiratory Syncytial Virus (RSV) as the main viral cause. RSV has been associated with annual respiratory disease outbreaks and bacterial co-infection has also been reported. This study is the first RSV epidemiological study in young children hospitalized with community-acquired pneumonia (CAP) in Belém city, Pará (Northern Brazil).MethodsWith the objective of determining the prevalence of RSV infection and evaluating the patients’ clinical and epidemiological features, we conducted a prospective study across eight hospitals from November 2006 to October 2007. In this study, 1,050 nasopharyngeal aspirate samples were obtained from hospitalized children up to the age of three years with CAP, and tested for RSV antigen by direct immunofluorescence assay and by Reverse Transcription Polymerase Chain Reaction (RT-PCR) for RSV Group identification.ResultsRSV infection was detected in 243 (23.1%) children. The mean age of the RSV-positive group was lower than the RSV-negative group (12.1 months vs 15.5 months, p<0.001) whereas gender distribution was similar. The RSV-positive group showed lower means of C-reactive protein (CRP) in comparison to the RSV-negative group (15.3 vs 24.0 mg/dL, p<0.05). Radiological findings showed that 54.2% of RSV-positive group and 50.3% of RSV-negative group had interstitial infiltrate. Bacterial infection was identified predominantly in the RSV-positive group (10% vs 4.5%, p<0.05). Rhinorrhea and nasal obstruction were predominantly observed in the RSV-positive group. A co-circulation of RSV Groups A and B was identified, with a predominance of Group B (209/227). Multivariate analysis revealed that age under 1 year (p<0.015), CRP levels under 48 mg/dL (p<0.001) and bacterial co-infection (p<0.032) were independently associated with the presence of RSV and, in the analyze of symptoms, nasal obstruction were independently associated with RSV-positive group (p<0.001).ConclusionThe present study highlights the relevance of RSV infection in hospitalized cases of CAP in our region; our findings warrant the conduct of further investigations which can help design strategies for controlling the disease.

Norovirus Infection in Children Admitted to Hospital for Acute Gastroenteritis in Belem, Para ´ , Northern Brazil

Noroviruses are the leading cause of epidemic, non‐bacterial outbreaks of acute gastroenteritis, and are also a major cause of sporadic acute gastroenteritis in infants. The aim of the present study was to identify norovirus infections in children not infected by rotavirus admitted to hospital for acute gastroenteritis in Belém. A total of 348 fecal specimens were obtained from children with diarrhea aged less than 5 years, all of whom had tested negative for rotavirus, between May 2008 and April 2010. Fecal samples were screened for norovirus antigen using enzyme‐immunoassay (EIA). Specimens were subjected to reverse‐transcription polymerase chain reaction (RT‐PCR) using the primers Mon432/434–Mon431/433 for detection of the GI and GII norovirus strains, respectively. Based on both methods, the overall norovirus positivity rate was 36.5% (127/348). Of the 169 samples collected in the first year, 44.4% (n = 75) tested positive for norovirus using both methods, 35.5% (n = 60) by EIA and 40.8% (n = 69) by RT‐PCR. Using RT‐PCR as a reference standard, a sensitivity of 78.3%, specificity of 94%, and agreement of 87.6% were recorded. Genome sequencing was obtained for 22 (31.9%) of the 69 positive samples, of which 90.9% (20/22) were genotype GII.4d and 9.1% (2/22) were genotype GII.b. Norovirus infection was most frequent in children under 2 years of age (41.5%–115/277). The peak incidence (62.1%) of norovirus‐related acute gastroenteritis in these patients (not infected by rotavirus) was observed in February 2010. These findings emphasize the importance of norovirus as a cause of severe acute gastroenteritis among children in Belém, Pará, Northern Brazil. J. Med. Virol. 85:737–744, 2013.

Molecular characterization of norovirus, sapovirus and astrovirus in children with acute gastroenteritis from Belém, Pará, Brazil

The importance of norovirus (NoVs), sapovirus (SaVs) and human astrovirus (HAstVs) as causes of gastroenteritis outbreaks is already well-defined, but a few studies have described sporadic cases of acute gastroenteritis caused by these viral entities. The aim of this study was to determine the role of these viruses in the etiology of acute gastroenteritis in children enrolled to participate in hospital – and emergency department – based intensive surveillance carried out in Belém, Brazil, from March to September 2003. A total of 305 stool specimens from patients with severe gastroenteritis were collected and screened by reverse transcription followed by polymerase chain reaction (RT-PCR), using the specific primers Mon 269 and Mon 270 for HAstVs, p289 and p290 for human calicivirus (HuCVs), and Mon 431/433 and Mon 432/434 for NoVs. Sequencing of RT-PCR HAstV, HuCV and NoV amplicons was carried out using the same primers. Of the 305 samples tested, 96 (31.5%) were positive, with 51 diagnosed as HuCVs, 40 as HAstVs and five as mixed infections. Of the 56 (18.4%) HuCVs sequenced, 30 were NoVs (9.8%) of genogroups GI-4 and GII-4, and 15 (4.9%) were SaVs of types GI-1, GI-2 and GII-1. HAstVs, including genotypes 1, 8 and 2, were detected in 45 (14.7%) samples. This study has highlighted the importance of these viruses as causes of acute gastroenteritis and established the circulation of different genotypes during the study period. These results reinforce the need for establishing an intensive surveillance for gastroenteritis caused by these viruses to assess the burden of disease and to monitor the circulation of genotypes.The importance of norovirus (NoVs), sapovirus (SaVs) and human astrovirus (HAstVs) as causes of gastroenteritis outbreaks is already well-defined, but a few studies have described sporadic cases of acute gastroenteritis caused by these viral entities. The aim of this study was to determine the role of these viruses in the etiology of acute gastroenteritis in children enrolled to participate in hospital – and emergency department – based intensive surveillance carried out in Belem, Brazil, from March to September 2003. A total of 305 stool specimens from patients with severe gastroenteritis were collected and screened by reverse transcription followed by polymerase chain reaction (RT-PCR), using the specific primers Mon 269 and Mon 270 for HAstVs, p289 and p290 for human calicivirus (HuCVs), and Mon 431/433 and Mon 432/434 for NoVs. Sequencing of RTPCR HAstV, HuCV and NoV amplicons was carried out using the same primers. Of the 305 samples tested, 96 (31.5%) were positive, with 51 diagnosed as HuCVs, 40 as HAstVs and five as mixed infections. Of the 56 (18.4%) HuCVs sequenced, 30 were NoVs (9.8%) of genogroups GI-4 and GII-4, and 15 (4.9%) were SaVs of types GI-1, GI-2 and GII-1. HAstVs, including genotypes 1, 8 and 2, were detected in 45 (14.7%) samples. This study has highlighted the importance of these viruses as causes of acute gastroenteritis and established the circulation of different genotypes during the study period. These results reinforce the need for establishing an intensive surveillance for gastroenteritis caused by these viruses to assess the burden of disease and to monitor the circulation of genotypes.

Siaα2-3Galβ1- Receptor Genetic Variants Are Associated with Influenza A(H1N1)pdm09 Severity

Different host genetic variants may be related to the virulence and transmissibility of pandemic Influenza A(H1N1)pdm09, influencing events such as binding of the virus to the entry receptor on the cell of infected individuals and the host immune response. In the present study, two genetic variants of the ST3GAL1 gene, which encodes the Siaα2-3Galβ1- receptor to which influenza A(H1N1)pdm09 virus binds for entry into the host cell, were investigated in an admixed Brazilian population. First, the six exons encoding the ST3GAL1 gene were sequenced in 68 patients infected with strain A(H1N1)pdm09. In a second phase of the study, the rs113350588 and rs1048479 polymorphisms identified in this sample were genotyped in a sample of 356 subjects from the northern and northeastern regions of Brazil with a diagnosis of pandemic influenza. Functional analysis of the polymorphisms was performed in silico and the influence of these variants on the severity of infection was evaluated. The results suggest that rs113350588 and rs1048479 may alter the function of ST3GAL1 either directly through splicing regulation alteration and/or indirectly through LD with SNP with regulatory function. In the study the rs113350588 and rs1048479 polymorphisms were in linkage disequilibrium in the population studied (D’ = 0.65). The GC haplotype was associated with an increased risk of death in subjects with influenza (OR = 4.632, 95% CI = 2.10;1.21). The AT haplotype was associated with an increased risk of severe disease and death (OR = 1.993, 95% CI = 1.09;3.61 and OR 4.476, 95% CI = 2.37;8.44, respectively). This study demonstrated for the first time the association of ST3GAL1 gene haplotypes on the risk of more severe disease and death in patients infected with Influenza A(H1N1)pdm09 virus.

Caracterização molecular de norovírus, sapovírus e astrovírus em crianças com gastroenterite aguda em Belém, Pará, Brasil

The importance of norovirus (NoVs), sapovirus (SaVs) and human astrovirus (HAstVs) as causes of gastroenteritis outbreaks is already well-defined, but a few studies have described sporadic cases of acute gastroenteritis caused by these viral entities. The aim of this study was to determine the role of these viruses in the etiology of acute gastroenteritis in children enrolled to participate in hospital – and emergency department – based intensive surveillance carried out in Belém, Brazil, from March to September 2003. A total of 305 stool specimens from patients with severe gastroenteritis were collected and screened by reverse transcription followed by polymerase chain reaction (RT-PCR), using the specific primers Mon 269 and Mon 270 for HAstVs, p289 and p290 for human calicivirus (HuCVs), and Mon 431/433 and Mon 432/434 for NoVs. Sequencing of RT-PCR HAstV, HuCV and NoV amplicons was carried out using the same primers. Of the 305 samples tested, 96 (31.5%) were positive, with 51 diagnosed as HuCVs, 40 as HAstVs and five as mixed infections. Of the 56 (18.4%) HuCVs sequenced, 30 were NoVs (9.8%) of genogroups GI-4 and GII-4, and 15 (4.9%) were SaVs of types GI-1, GI-2 and GII-1. HAstVs, including genotypes 1, 8 and 2, were detected in 45 (14.7%) samples. This study has highlighted the importance of these viruses as causes of acute gastroenteritis and established the circulation of different genotypes during the study period. These results reinforce the need for establishing an intensive surveillance for gastroenteritis caused by these viruses to assess the burden of disease and to monitor the circulation of genotypes.The importance of norovirus (NoVs), sapovirus (SaVs) and human astrovirus (HAstVs) as causes of gastroenteritis outbreaks is already well-defined, but a few studies have described sporadic cases of acute gastroenteritis caused by these viral entities. The aim of this study was to determine the role of these viruses in the etiology of acute gastroenteritis in children enrolled to participate in hospital – and emergency department – based intensive surveillance carried out in Belem, Brazil, from March to September 2003. A total of 305 stool specimens from patients with severe gastroenteritis were collected and screened by reverse transcription followed by polymerase chain reaction (RT-PCR), using the specific primers Mon 269 and Mon 270 for HAstVs, p289 and p290 for human calicivirus (HuCVs), and Mon 431/433 and Mon 432/434 for NoVs. Sequencing of RTPCR HAstV, HuCV and NoV amplicons was carried out using the same primers. Of the 305 samples tested, 96 (31.5%) were positive, with 51 diagnosed as HuCVs, 40 as HAstVs and five as mixed infections. Of the 56 (18.4%) HuCVs sequenced, 30 were NoVs (9.8%) of genogroups GI-4 and GII-4, and 15 (4.9%) were SaVs of types GI-1, GI-2 and GII-1. HAstVs, including genotypes 1, 8 and 2, were detected in 45 (14.7%) samples. This study has highlighted the importance of these viruses as causes of acute gastroenteritis and established the circulation of different genotypes during the study period. These results reinforce the need for establishing an intensive surveillance for gastroenteritis caused by these viruses to assess the burden of disease and to monitor the circulation of genotypes.

Ocorrência de Bocavírus Humano associado às infecções respiratórias agudas em crianças de 0 a 2 anos de idade na Cidade de Belém, Pará, Brasil

INTRODUCTION: Acute Respiratory Infections (ARI) are one of the main public health problems in the world. Most of these infections are associated with several pathogens, and viruses are the most prevalent agents. Recently, a new parvovirus named Human Bocavirus (HBoV) has been described. Investigations on the relationship between this new agent and cases of ARI in individuals are still scarce. Herein, we review a study of HBoV in a population segment in the Amazon. MATERIALS AND METHODS: In this study, samples of nasopharyngeal aspirates from patients with ARI treated in Health Care Units in Belem, Brazil, were analyzed. Identification of the virus was carried out by polymerase chain reaction using pairs of specific oligonucleotides, followed by phylogenetic analysis of the nucleotide sequences obtained. RESULTS: Of the 397 samples studied, three specimens were HBoV-positive, and one presented as a co-infection with the respiratory syncytial virus. DISCUSSION: The positivity rate obtained in this investigation was lower than that described in other studies; however, previous studies involved hospitalized patients, which constitute a different population group. The phylogenetic analyses revealed a significant similarity between the virus strains found and those previously described. CONCLUSION: This is the first report associating HBoV with ARI in the Amazon.INTRODUCTION: Acute Respiratory Infections (ARI) are one of the main public health problems in the world. Most of these infections are associated with several pathogens, and viruses are the most prevalent agents. Recently, a new parvovirus named Human Bocavirus (HBoV) has been described. Investigations on the relationship between this new agent and cases of ARI in individuals are still scarce. Herein, we review a study of HBoV in a population segment in the Amazon. MATERIALS AND METHODS: In this study, samples of nasopharyngeal aspirates from patients with ARI treated in Health Care Units in Belém, Brazil, were analyzed. Identification of the virus was carried out by polymerase chain reaction using pairs of specific oligonucleotides, followed by phylogenetic analysis of the nucleotide sequences obtained. RESULTS: Of the 397 samples studied, three specimens were HBoV-positive, and one presented as a co-infection with the respiratory syncytial virus. DISCUSSION: The positivity rate obtained in this investigation was lower than that described in other studies; however, previous studies involved hospitalized patients, which constitute a different population group. The phylogenetic analyses revealed a significant similarity between the virus strains found and those previously described. CONCLUSION: This is the first report associating HBoV with ARI in the Amazon.

Detecção e caracterização de adenovírus humano proveniente de casos de paralisia flácida aguda, na Região Norte do Brasil

The human adenovirus (HAdV) cause a variety of infections such as acute respiratory, gastrointestinal, ocular, urinary tract and also serious neurological syndromes. The present study aimed to identify and characterize HAdV in stool samples of patients from the Northern region of Brazil in the period of 1998 to 2012, with acute flaccid paralysis, negative for poliovirus and enterovirus nonpolio. In this study, 19 samples showed a characteristic cytopathic effect of HAdV when inoculated in HEp2-C and L20B lineages. These samples were subjected by the polymerase chain reaction (PCR) in real-time (qPCR) and partial nucleotide sequencing of the hexon gene. Of the total samples, 13 were confirmed by qPCR, PCR and nucleotide sequencing. Genetic analysis showed the following viral characterization: one sample of HAdV-F41; three samples of HAdV-A31 and nine species C, three of HAdV-C5-C6 and six of HAdV. The positive samples were from the States of Pará (6/19 – 31.6%), Amazonas (6/19 –31.6%) and Acre (1/19 – 5.2%). In relation to the age group, from 13 positive cases, 12 were children under 5 years old, representing 92.3% of cases. The results suggest a possible HAdV participation in the etiology of acute flaccid paralysis occurred in Northern Brazil.

Primeira detecção de coronavírus humano associado à infecção respiratória aguda na Região Norte do Brasil

Los coronavirus humanos (CoVh) son los responsables por ocasionar enfermedades respiratorias y entericas, siendo asociados a las infecciones agudas y graves del trato respiratorio. El objetivo de este trabajo fue el de identificar los episodios de CoVh en pacientes con infeccion respiratoria aguda (IRA) en la Ciudad de Belem, en el Estado de Para, Brasil, atendidas por el programa de vigilancia del virus influenza del Instituto Evandro Chagas. En el periodo comprendido entre agosto de 2009 a marzo de 2011, muestras de aspirado nasofaringeo o frotis combinado (nasal y oral) obtenidas de 308 pacientes con diagnostico clinico de IRA, fueron investigadas en laboratorio a la busqueda de evidencias de infeccion por CoVh. La metodologia adoptada abarco cuatro etapas principales: a) extraccion del RNA viral (RNAv) del especimen clinico; b) ejecucion de la tecnica de reaccion en cadena mediada por la polimerasa precedida de transcripcion reversa (RT-PCR); c) electroforesis en gel de agarosa de los productos generados; y d) secuenciacion genetica de nucleotidos. El procesamiento de laboratorio de todos los especimenes se revelo positivo para CoVh en una muestra clinica de los pacientes investigados. El analisis filogenetico de la muestra positiva permitio clasificarla como perteneciente al subtipo OC43 de CoVh. El presente hallazgo representa la primera comprobacion en laboratorio de la circulacion de este agente viral en la Region Amazonica. Son necesarios estudios adicionales para un mayor conocimiento de la etiologia y la epidemiologia de este agente viral en casos de IRA que ocurren en la Region Norte de Brasil

Caracterización molecular de norovirus, sapovirus y astrovirus en niños con gastroenteritis aguda en Belém (Pará, Brasil)

The importance of norovirus (NoVs), sapovirus (SaVs) and human astrovirus (HAstVs) as causes of gastroenteritis outbreaks is already well-defined, but a few studies have described sporadic cases of acute gastroenteritis caused by these viral entities. The aim of this study was to determine the role of these viruses in the etiology of acute gastroenteritis in children enrolled to participate in hospital – and emergency department – based intensive surveillance carried out in Belém, Brazil, from March to September 2003. A total of 305 stool specimens from patients with severe gastroenteritis were collected and screened by reverse transcription followed by polymerase chain reaction (RT-PCR), using the specific primers Mon 269 and Mon 270 for HAstVs, p289 and p290 for human calicivirus (HuCVs), and Mon 431/433 and Mon 432/434 for NoVs. Sequencing of RT-PCR HAstV, HuCV and NoV amplicons was carried out using the same primers. Of the 305 samples tested, 96 (31.5%) were positive, with 51 diagnosed as HuCVs, 40 as HAstVs and five as mixed infections. Of the 56 (18.4%) HuCVs sequenced, 30 were NoVs (9.8%) of genogroups GI-4 and GII-4, and 15 (4.9%) were SaVs of types GI-1, GI-2 and GII-1. HAstVs, including genotypes 1, 8 and 2, were detected in 45 (14.7%) samples. This study has highlighted the importance of these viruses as causes of acute gastroenteritis and established the circulation of different genotypes during the study period. These results reinforce the need for establishing an intensive surveillance for gastroenteritis caused by these viruses to assess the burden of disease and to monitor the circulation of genotypes.The importance of norovirus (NoVs), sapovirus (SaVs) and human astrovirus (HAstVs) as causes of gastroenteritis outbreaks is already well-defined, but a few studies have described sporadic cases of acute gastroenteritis caused by these viral entities. The aim of this study was to determine the role of these viruses in the etiology of acute gastroenteritis in children enrolled to participate in hospital – and emergency department – based intensive surveillance carried out in Belem, Brazil, from March to September 2003. A total of 305 stool specimens from patients with severe gastroenteritis were collected and screened by reverse transcription followed by polymerase chain reaction (RT-PCR), using the specific primers Mon 269 and Mon 270 for HAstVs, p289 and p290 for human calicivirus (HuCVs), and Mon 431/433 and Mon 432/434 for NoVs. Sequencing of RTPCR HAstV, HuCV and NoV amplicons was carried out using the same primers. Of the 305 samples tested, 96 (31.5%) were positive, with 51 diagnosed as HuCVs, 40 as HAstVs and five as mixed infections. Of the 56 (18.4%) HuCVs sequenced, 30 were NoVs (9.8%) of genogroups GI-4 and GII-4, and 15 (4.9%) were SaVs of types GI-1, GI-2 and GII-1. HAstVs, including genotypes 1, 8 and 2, were detected in 45 (14.7%) samples. This study has highlighted the importance of these viruses as causes of acute gastroenteritis and established the circulation of different genotypes during the study period. These results reinforce the need for establishing an intensive surveillance for gastroenteritis caused by these viruses to assess the burden of disease and to monitor the circulation of genotypes.