Navegando por Assunto "Gastroenterite"

Agora exibindo 1 - 10 de 10

Acesso aberto (Open Access)
Análise filogenética de genes de provável origem não humana de rotavírus do grupo A em espécimes fecais de crianças com gastrenterite aguda provenientes de Belém, Brasil
(Universidade Federal do Pará, 2012) MAESTRI, Régis Piloni; MASCARENHAS, Joana D'Arc Pereira; http://lattes.cnpq.br/5156164089432435
Rotaviruses (RVs) are the main cause of acute viral gastroenteritis in both humans and young animals of species such as calves, horses, pigs, dogs, cats, and birds. The genetic diversity of RVs is related to a variety of evolutionary mechanisms, including point mutation, genome reassortment, and reassortment. The objective of this study was realized the molecular charaxterization of the genes that encode structural and nonstructural proteins in unusual RV strains. The clinical specimens selected for this study were obtained from children and newborns with RV gastroenteritis, who participated in research projects on viral gastroenteritis conducted at the Evandro Chagas Institute. Structural (VP1-VP4, VP6, and VP7) and nonstructural (NSP1-NSP6) genes were amplified from stool samples by the polymerase chain reaction and subsequently sequenced. Eight unusual RV strains isolated from children and newborns with gastroenteritis were studied. Reassortments between genes of animal origin were observed in 5/8 (62.5%) strains analyzed. These results demonstrate that, although rare, interspecies (animal-human) transmission of RVs occurs in nature, as observed in the present study in strains NB150, HSP034, HSP180, HST327, and RV10109. This study is the first of its kind conducted in the Amazon region and supports previous data showing a close relationship between genes of human and animal origin, representing a challenge to the large-scale introduction of RV vaccines in national immunization programs.
Acesso aberto (Open Access)
Análise molecular dos genes VP4, VP7 e NSP4 de rotavírus do tipo G1 circulantes em Belém e Marituba, Pará, Brasil, de 1982 a 2008
(Universidade Federal do Pará, 2011) SOARES, Luana da Silva; MASCARENHAS, Joana D'Arc Pereira; http://lattes.cnpq.br/5156164089432435; LINHARES, Alexandre da Costa; http://lattes.cnpq.br/3316632173870389
Rotaviruses are major viral agents of acute gastroenteritis and responsible for 36% of hospitalization for diarrhea among children less than five years of age, resulting in 453.000 deaths annually, mostly in developing countries. Rotavirus is a member of Reoviridae family, and its genome consists of 11 double-stranded RNA (dsRNA) which encode 12 proteins. G1 rotavirus is commonly detected in epidemiological investigations, occurring under different prevalence rates. The aim of this study was to analyze the VP4, VP7 and NSP4 diversity genetic of G1 rotavirus circulating in Belém and Marituba, Pará, Brazil, from 1982 to 2008. We selected 83 samples previously characterized as G1 type and submitted to RT-PCR. The samples were from seven studies conducted in IEC. It was possible amplification for 63 (75.9%) specimens. Lineages 1 (8/63, 12.7%), 2 (29/63, 46.0%), 3 (18/63, 28.6%) and 9 (8/63, 12.7%) of VP7 gene were detected. The sublineages 2E and 3A were co-predominant detected in 57.1% (36/63) of samples. Three amino acid substitutions (97 [D→E], 147 [S→N] and 218 [I→V]) were observed in VP7 antigenic regions (A, B and C) in samples of 1, 2 and 9 lineages. All samples showed P[8] specificity for VP4 gene and lineages 2 (21/63, 33.3%) and 3 (42/63, 66.7%) were detected. Two substitutions (35 [I→V] and 38 [S→G]) occurred in antigenic region of VP4 of samples analyzed. For NSP4 gene, all samples belonged to E1 type. Phylogenetic analysis of NSP4 gene revealed that occurred changes in nucleotide positions 47 (C→T) and 101 (T→C), resulting in amino acid substitutions at positions 16 (S→P) and 34 (L → P) in all samples and 9 specimens displayed amino acid substitution in NSP4 toxicity residue (aa 131). This study allowed us to broaden our understanding about genetic diversity and circulation of G1 variants and represents the first molecular epidemiology analyze of this genotype in Brazil corroborating the high heterogeneity of this genotype.
Acesso aberto (Open Access)
Caracterização antigênica e molecular de amostras de rotavírus do tipo G1, obtidas de crianças participantes de estudos em gastroenterites virais, no período de 1982 a 2003, em Belém, Pará, Brasil
(Universidade Federal do Pará, 2006-07-03) SOARES, Luana da Silva; MASCARENHAS, Joana D'Arc Pereira; http://lattes.cnpq.br/5156164089432435; LINHARES, Alexandre da Costa; http://lattes.cnpq.br/3316632173870389
Infant mortality remains an important problem of public health worldwide, mainly in developing countries. Of more than the 50 etiologic agents implied in this disease, rotavirus causes 111 million episodes of diarrhoea, resulting in more than 600,000 deaths among children less than five years, of which 82% are notified in the poorest countries of the world. This study aimed at the antigenic and molecular characterization of G1 rotavirus strains among children participanting of viral gastroenteritis studies, carried out from 1982 to 2003, in Belém, Pará, Brazil. One hundred and forty-eight specimens of G1 rotavirus were analyzed in the present investigation. Overall, the prevalence of the G1 type was of 41.3%, being that frequencies of this genotype through studies ranged from 11.0% to 67.6%. Eletropherotypes, G serotypes and P genotypes characterization of G1 rotavirus occurred in frequencies of 78.4%, 89.9% and 87.8%, respectively. Three long eletropherotypes varieties were identified, being that the L1 variety was found frequently (79.3%). The G1, G9 and G1+G4 serotypes were detected in 88.0%, 9.8% and 2.2% of the specimens, respectively. Mixed infection by G1+G4 genotype was detected in one sample. The prevalent binary combination was P[8],G1, being responsible for 72.3% of the cases. Mixed infections circulated in percentage of 20.0%, including genotypes P[4]+P[8],G1, P[6]+P[8],G1, P[4]+P[6],G1, P[4]+P[6]+P[8],G1 and P[6]+P[8],G1+G4. The G1 genotype circulated among 2nd to 35th months of age and a highest number of cases was registered between 6 to 16 months of age. Clinical severity differences among G1 and other genotypes of rotavirus were not verified. The present analysis gathers pioneer findings in Brazil, allowing to extend the knowledge concerning the antigenic and molecular diversity of the infections by G1 rotavirus and these results will allow to understand the genetic complexity of such viral agents.
Acesso aberto (Open Access)
Detecção de adenovírus humanos em amostras de água superficial e esgoto não tratado oriundas de diversos ecossistemas aquáticos da cidade de Belém-PA
(Universidade Federal do Pará, 2012) SPADA, Paula Katharine de Pontes; MENDES, Yvone Gabbay
The enteric viruses are important agents of waterborne diseases. Among these, the human adenovirus (HAdV) assumed importance because they are a major cause of gastroenteritis in children under five years and by its high resistance to physical and chemical factors in the detriment of other viruses in the environment. Several studies have shown no relationship between the presence of indicator bacteria and viruses. Therefore, several authors have suggested the inclusion of these agents as potential indicators of viral and fecal water contamination. The aim of this study was to detect the presence of HAdV in water samples and untreated sewage originating from many aquatic ecosystems from Belém-PA. Six sampling points were selected, among them an untreated sewage: Esgoto do UNA and five catch basins: Porto do Açaí, Ver-o-Peso, Igarapé Tucunduba, Lago Bolonha and Lago Água Preta. A month collection of two liters of water was realized in each point for 24 consecutive months, from Nov/2008 to Oct/2010, in a total of 144 samples. Sterile distilled water was used as negative control for each point and in all tests. The samples were concentrated by adsorption-elution method and then centrifuged to obtain two ml. The DNA was extracted by the Qiagen commercial kit. Were employed the polymerase chain reaction (PCR) and real-time PCR for molecular detection, with specific primers and probes to amplify a specific hexon gene of 301 and 96 bp, respectively. In order to improve the amplified product for genomic sequencing, some samples positive by PCR were subjected to nested PCR using an additional pair of primers that amplify an internal region of 171 bp. Water and sewage samples were sequenced, analyzed and compared to other obtained from GenBank. The HAdV were detected in 59% (85/144) of samples of surface water and untreated sewage. The positivity obtained by PCR was 22,9% (33/144) and by real-time PCR 58.7% (84/143). The first technique detected the virus only in samples from the Igarapé Tucunduba (62,5%) and Esgoto do UNA (75%) and the second in samples from the six points of collection (variation of 25% to 100%). The agent was detected in all the 24 months of the study, being present in at least two points monthly. The real-time PCR was more sensitive in this study, having found the agent in 36,4% (52/143) of samples not detected by PCR. Of the eight samples genotyped all belong to the species F, four related to serotype 40 and four to 41. Our results confirm the high circulation of these pathogens in surface water and sewage of the city, suggesting the inclusion of HAdVs as good indicators fecal and viral contamination of the water. The study of these viruses in aquatic environments is pioneer in Belém and these results are of relevant importance for public health policies and environmental, serving as a basis for further studies in this area.
Acesso aberto (Open Access)
Eficácia clínica da vacina tetravalente (RRV-TV) contra rotavírus em Belém, Pará
(Universidade Federal do Pará, 1999-06-17) OLIVEIRA, Consuelo Silva de; LINHARES, Alexandre da Costa; http://lattes.cnpq.br/3316632173870389; BATISTA, Nildo Alves; http://lattes.cnpq.br/9347541615414055
There is currently growing evidence that infantile rotavirus gastroenteritis will be controlled only through the development of an effective vaccine targeted for use in early childhood. This study was conducted with the aim of assessing the protective efficacy of the lower-titer rhesus-human reassortant rotavirus tetravalent vaccine (RRV-TV, 4 x 104 ) against the major clinical indicators of severity cases of rotavirus diarrhoea; for this, were re-examined 91 rotavirus-associated diarrhoeal episodes that were recorded during an efficacy trial carried out previously in Belem, Para, Brazil. The source of information for study were the data recorded in field forms used to perform the routine surveillance for diarrhoeal episodes, as well as those forms in which daily clinical records were made while diarrhoea persisted. Relative efficacy was specifically against the following clinical parameters: a) duration of diarrhoea; b) maximum number of liquid /semiliquid stools per day; c) duration of vomiting episodes/24h; d) maximum number of vomiting episodes / 24h; e) fever (rectal temperature); f) dehydration; and g) need for treatment. The overall clinical severity of rotavirus gastroenteritis has been graded using a numerical twenty-point scoring system (i.e., maximum of 20 points) which allowed the classification of diarrhoeal cases in mild (0-6 scoring interval), moderate/severe (9- 14) and very severe (>14). A significant (p<0.05) protection conferred by RRV-TV was observed in five of the seven clinical parameters under analysis, as follows: a) duration of diarrhoea (52%, pure rotavirus diarrhoea; b) maximum number of liquid/semi-liquid stools per day (42% and 53% against all- and- pure diarrhoeal episodes, respectively); c) maximum number of vomiting (56% and 62% for all-andpure diarrhoeal cases, respectively); d) dehydration (42% and 48% against all-andpure cases of diarrhoea, respectively); and e) the need for rehidration (42% and 46% for all-and-pure cases, respectively). High protective efficacy levels were achieved against rotavirus type G2-related diarrhoea during the second year of follow-up, if considered both the number-and-the maximum number vomiting episodes: 90% and 100%, respectively. Also for G2 type, the overall cumulative protection of 100% against those episodes scored greater than 14. Similar rates of protection against mixed - (35%) and - pure (37%) rotavirus gastroenteritis were yielded after two years of follow-up. While no efficacy was achieved against mild (0- 8 scored) diarrhoea, RRV-TV was 75% (p = 0.02) efficacious against the very severe cases of rotavirus gastroenteritis; there was a tendency for protection against alland- pure diarrhoeal episodes with clinical scores ranging from 9 to 14: 44% (p = 0.06) and 45% (p = 0.08), respectively. The results of study support the view that RRV-TV appears to selectively protect against the most severe rotavirus disease.
Acesso aberto (Open Access)
Eficácia e segurança de uma vacina oral de rotavírus humano atenuado contra gastroenterite grave por rotavírus, durante os primeiros dois anos de vida em crianças em Belém, Pará, Brasil
(Universidade Federal do Pará, 2009) JUSTINO, Maria Cleonice Aguiar; ARAÚJO, Eliete da Cunha; http://lattes.cnpq.br/5906453187927460; LINHARES, Alexandre da Costa; http://lattes.cnpq.br/3316632173870389
Rotaviruses are recognised as the leading cause of severe gastroenteritis in children aged less than five years in both developed and developing countries, with highest incidence rates between 6 and 24 months of life. On a global scale, recent estimates indicate that annually rotaviruses cause at least 500,000 deaths. A large phase III clinical trial was undertaken in 11 Latin American countries and Finland with an attenuated, human-derived vaccine strain, including recruitment of more than 63,000 children. This was a randomised, double-blind, placebo-controlled trial in which more than 63,000 infants were randomly assigned to receive two oral doses of either RIX4414 or placebo at a proportion of 1:1. The main purposed of this study was to evaluate both protective efficacy and safety of RIX4414. As part of the original study, 3,218 children were enrolled in Belém, Pará, to whom two doses of either vaccine or placebo were administered at 2 and 4 months of age. A subset of infants (n = 653) was evaluated throughout 1 – 2 years in order to assess efficacy of RIX4414 vaccine. Overall, 37 gastroenteritis episodes of severe rotavirus gastroenteritis were recorded of which 75.6% (28/37) and 24% (9/37) in the placebo and vaccine recipients, respectively. The level of rotavirus vaccine protection was higher [83% (CI95% 22 – 96)] against very severe rotavirus gastroenteritis, yielding a ≥ 15 score as calculated with a 20-point Ruuska & Vesikari scale. The cumulative hazard of a first episode of severe gastroenteritis was about four-fold lower in the vaccine group throughout the 2-years’ efficacy period, as compared to the placebo group. The protection rates against severe gastroenteritis caused by G1- and- non-G1 serotypes were 51% (CI95% -30-81) and 82% (CI95% 37-95), respectively, denoting efficacies against rotavirus strains both homologous and heterologous to the vaccine strain. Of importance, the vaccine afforded significant protection [93% (CI95%47-99)] against G9 serotype which has been regarded as a globally emergent strain, besides of being related to more severe gastroenteritis. Also reflecting a vaccine efficacy, there was a significant reduction, by 35.3% (CI95% 11.6-52.9), in the rate of allcause hospitalisation for gastroenteritis, a finding of potential major public health impact. With regards to safety of RIX4414 vaccine, there were no overall statistically significant differences when the rates of serious adverse events were compared for vaccine group and placebo group. No cases of intussusception were reported during the entire follow-up period, through broad and active surveillance in paediatric clinics in the study area. Results obtained in this study confirm previous findings from worldwide several multi-centric trials that sustain both protective efficacy and safety of RIX4414 when administered in a 2-dose schema to healthy infants.
Acesso aberto (Open Access)
Oral live attenuated human rotavirus vaccine (RotarixTM) offers sustained high protection against severe G9P[8] rotavirus gastroenteritis during the first two years of life in Brazilian children
(2012-11) JUSTINO, Maria Cleonice Aguiar; ARAÚJO, Eliete da Cunha; VAN DOORN, Leen-Jan; OLIVEIRA, Consuelo Silva de; GABBAY, Yvone Benchimol; MASCARENHAS, Joana D'Arc Pereira; MIRANDA, Yllen Stefania Affonso; GUERRA, Sylvia de Fátima dos Santos; SILVA, Veronilce Borges da; LINHARES, Alexandre da Costa
In a large Phase III trial conducted in 10 Latin American countries, the safety and efficacy of the live attenuated monovalent rotavirus vaccine RIX4414 was evaluated in 15,183 healthy infants followed up during the first two years of life. Belém was the only site in Brazil included in this multicentre trial. The study in Belém included a subset of 653 infants who were followed up until 24 months of age for protection against severe rotavirus gastroenteritis. These subjects were randomly assigned in a 1:1 ratio to receive two doses of vaccine (n = 328) or two doses of placebo (n = 325) at approximately two and four months of age. Of the 653 enrolled infants, 23 dropped out during the study period. For the combined two-year period, the efficacy of RIX4414 was 72.3% [95% confidence interval (CI) 37.5-89.1%] against severe rotavirus-related gastroenteritis, reaching a protection rate of 81.8% (95% CI 36.4-96.6%) against circulating wild-type G9 rotavirus strains. It is concluded that two doses of RIX4414 are highly efficacious against severe rotavirus gastroenteritis in Belém during the first two years of life and provide high protection against the worldwide emergence and spread of G9P[8] strains.
Acesso aberto (Open Access)
Sapoviruses in children with acute gastroenteritis from Manaus, Amazon region, Brazil, 2010-2011
(Universidade Federal do Pará, 2016-11-03) REYMÃO, Tammy Kathlyn Amaral; HERNANDEZ, Juliana das Merces; COSTA, Samya Thalita Picanço da; SOUSA, Maisa Silva de; OLIVEIRA, Darleise de Souza; SILVA, Luciana Damascena da; BANDEIRA, Renato da Silva; LIMA, Ian Carlos Gomes de; SOARES, Luana da Silva; MASCARENHAS, Joana D'Arc Pereira; GABBAY, Yvone Benchimol
Sapoviruses (SaVs) are responsible for acute gastroenteritis in humans, especially children and the elderly. In Brazil, data on SaVs infections are very limited, especially in Northern Brazil. Here, we investigated the occurrence of SaVs in samples from hospitalized children under ten years old that presented acute gastroenteritis. Positive samples were genotyped and phylogenetic analysis was performed using prototype strains sequences obtained from GenBank database. In total, 156 fecal samples were screened by RT-PCR for SaVs. A positivity rate of 3.8% (6/156) was found in children under three years of age. Four genotypes were detected: GI.I, GI.2 and GII.2?-GII.4?/GII.4, suggesting a possible inter-genotypes recombination. Most infections (83.3%) occurred between August and September. The positivity was similar to that found in other countries and genotyping demonstrated the presence of distinct genotypes. To our knowledge, this is the first study reporting the circulation of SaVs in Manaus, state of Amazonas, Amazon region, Brazil.
Acesso aberto (Open Access)
Segurança, imunogenicidade e eficácia protetora de duas doses da vacina RIX4414 contendo rotavírus atenuado de origem humana
(2007-06) ARAÚJO, Eliete da Cunha; CLEMENS, Sue Ann C.; OLIVEIRA, Consuelo Silva de; JUSTINO, Maria Cleonice Aguiar; RUBIO, Pilar; GABBAY, Yvone Benchimol; SILVA, Veronilce Borges da; MASCARENHAS, Joana D'Arc Pereira; CAVALCANTE, Vânia Lúcia Noronha; CLEMENS, Ralf; GUSMÃO, Rosa Helena Porto; SANCHEZ, Nervo; MONTEIRO, Talita Antonia Furtado; LINHARES, Alexandre da Costa
Objective: To determine the safety, immunogenicity and efficacy of two doses of rotavirus vaccine in healthy Brazilian infants. Methods: A randomized, multicenter, double-blind, placebo-controlled trial was conducted in Brazil, Mexico and Venezuela. Infants received two oral doses of vaccine or placebo at 2 and 4 months of age, concurrently with routine immunizations, except for oral poliomyelitis vaccine (OPV). This paper reports results from Belém, Brazil, where the number of subjects per group and the viral vaccine titers were: 194 (104.7 focus forming units – FFU), 196 (105.2 FFU), 194 (105.8 FFU) and 194 (placebo). Anti-rotavirus (anti-RV) antibody response was assessed in 307 subjects. Clinical severity of gastroenteritis episodes was measured using a 20-point scoring system with a score of ≥ 11 defined as severe GE. Results: The rates of solicited general symptoms were similar in vaccine and placebo recipients. At 2 months after the second dose, a serum IgA response to RV occurred in 54.7 to 74.4% of vaccinees. No interference was seen in the immunogenicity of routine vaccines. Vaccine efficacy against any rotavirus gastroenteritis (RVGE) was 63.5% (95%CI 20.8-84.4) for the highest concentration (105.8 FFU). Efficacy was 81.5% (95%CI 44.5-95.4) against severe RVGE. At its highest concentration (105.8 FFU), RIX4414 provided 79.8% (95%CI 26.4-96.3) protection against severe RVGE by G9 strain. Conclusions: RIX4414 was highly immunogenic with a low reactogenicity profile and did not interfere with seroresponse to diptheria, tetanus, pertussis, hepatitis B and Hib antigens. Two doses of RIX4414 provided significant protection against severe GE caused by RV.
Acesso aberto (Open Access)
Vacinas contra rotavírus e papilomavírus humano (HPV)
(Universidade Federal do Pará, 2016-07) LINHARES, Alexandre da Costa; VILLA, Luisa Lina
Objective: To briefly review strategies aimed at the development of rotavirus and HPV vaccines, with emphasis on the current status of studies assessing the safety, reactogenicity, immunogenicity and efficacy of recently developed vaccines. Sources of data: This review focuses on articles published from 1996 to 2006, mainly those from the last five years, with special emphasis on data obtained from recently completed studies involving a new live attenuated human rotavirus vaccine and a virus-like particle (HPV) vaccine. Summary of the findings: Strategies for developing rotavirus vaccines ranged from Jennerian approaches to the new human-derived rotavirus vaccine. Currently, two rotavirus vaccines are recognized as both efficacious and safe: a pentavalent human-bovine reassortant vaccine and a vaccine derived from an attenuated rotavirus of human origin. The second of these has been evaluated in more than 70,000 infants all over the world. Prophylactic vaccines against HPV have been tested in more than 25,000 young individuals around the world. Results from phase II and III clinical studies indicate that such vaccines against the most common types of HPV, those linked to both genital warts and 70% of cervical cancers, are safe and highly efficacious. Conclusions: A future rotavirus immunization program covering 60 to 80% of infants worldwide is likely to reduce by at least 50% the number of rotavirus-associated hospitalizations and deaths. It is also reasonable to expect that implementation of HPV prophylactic vaccines will reduce the burden of the HPV-related diseases that presently impact millions of people around the world.