RESUMO
INTRODUCTION: Rotavirus is a leading cause of severe diarrheal disease and death in children under five years of age worldwide. Vaccination is one of the most important public health interventions to reduce this significant burden. AREAS COVERED: This literature review examined vaccination coverage, hospitalization rate, mortality, genotypic distribution, immunogenicity, cost-effectiveness, and risk versus benefit of rotavirus vaccination in children in South America. Nine out of twelve countries in South America currently include a rotavirus vaccine in their national immunization program with coverage rates in 2022 above 90%. EXPERT OPINION: Introduction of the rotavirus vaccination has led to a marked reduction in hospitalizations and deaths from diarrheal diseases in children under 5 years, particularly infants under 1 year, in several South American countries. In Brazil, hospitalizations decreased by 59% and deaths by 21% (30-38% in infants). In Peru, hospitalizations in infants fell by 46% and deaths by 37% (56% in infants). Overall, data suggest that rotavirus vaccination has reduced rotavirus deaths by 15-50% in various South American countries. There is some evidence that immunity wanes after the age of 1-year old. Ongoing surveillance of vaccine coverage and changes in morbidity and mortality is important to maximize protection against this disease.
Assuntos
Diarreia , Hospitalização , Programas de Imunização , Infecções por Rotavirus , Vacinas contra Rotavirus , Humanos , Vacinas contra Rotavirus/administração & dosagem , Vacinas contra Rotavirus/imunologia , Infecções por Rotavirus/prevenção & controle , Infecções por Rotavirus/epidemiologia , Diarreia/prevenção & controle , Diarreia/epidemiologia , Diarreia/virologia , Lactente , Hospitalização/estatística & dados numéricos , América do Sul/epidemiologia , Pré-Escolar , Vacinação/estatística & dados numéricos , Análise Custo-Benefício , Rotavirus/imunologia , Cobertura Vacinal/estatística & dados numéricos , Efeitos Psicossociais da DoençaRESUMO
BACKGROUND: Although live attenuated monovalent human rotavirus vaccine (Rotarix) efficacy has been characterized through randomized studies, its effectiveness, especially in non-clinical settings, is less clear. In this study, we estimate the impact of childhood Rotarix® vaccination on community rotavirus prevalence. METHODS: We analyse 10 years of serial population-based diarrhoea case-control study, which also included testing for rotavirus infection (n = 3430), and 29 months of all-cause diarrhoea active surveillance from a child cohort (n = 376) from rural Ecuador during a period in which Rotarix vaccination was introduced. We use weighted logistic regression from the case-control data to assess changes in community rotavirus prevalence (both symptomatic and asymptomatic) and all-cause diarrhoea after the vaccine was introduced. We also assess changes in all-cause diarrhoea rates in the child cohort (born 2008-13) using Cox regression, comparing time to first all-cause diarrhoea case by vaccine status. RESULTS: Overall, vaccine introduction among age-eligible children was associated with a 82.9% reduction [95% confidence interval (CI): 49.4%, 94.2%] in prevalence of rotavirus in participants without diarrhoea symptoms and a 46.0% reduction (95% CI: 6.2%, 68.9%) in prevalence of rotavirus infection among participants experiencing diarrhoea. Whereas all age groups benefited, this reduction was strongest among the youngest age groups. For young children, prevalence of symptomatic diarrhoea also decreased in the post-vaccine period in both the case-control study (reduction in prevalence for children <1 year of age = 69.3%, 95% CI: 8.7%, 89.7%) and the cohort study (reduction in hazard for receipt of two Rotarix doses among children aged 0.5-2 years = 57.1%, 95% CI: 16.6, 77.9%). CONCLUSIONS: Rotarix vaccination may suppress transmission, including asymptomatic transmission, in low- and middle-income settings. It was highly effective among children in a rural community setting and provides population-level benefits through indirect protection among adults.
Assuntos
Infecções por Rotavirus , Rotavirus , Adulto , Idoso , Estudos de Casos e Controles , Criança , Pré-Escolar , Estudos de Coortes , Equador/epidemiologia , Humanos , Lactente , Prevalência , Infecções por Rotavirus/epidemiologia , Infecções por Rotavirus/prevenção & controle , População Rural , VacinaçãoRESUMO
Epidemiological data on species A rotavirus (RVA) infections have demonstrated the genetic diversity of strains circulating worldwide. Many G and P genotype combinations have been described over the years, varying regionally and temporally, especially in developing countries. However, the most common G and P genotype combinations identified in RVA human strains worldwide are G1P[8], G2P[4], G3P[8], G4P[8] and G9P[8]. RVA genotype G1P[8] strains are responsible for more than 50% of child infections worldwide and component of the two vaccines (Rotarix® [RV1] and RotaTeq® [RV5]) licensed globally. For a better understanding of the evolutionary mechanisms of this genotype in Brazil, phylogenetic analyses based on the 11 RVA genome segments (genomic constellation) from 90 G1P[8] RVA strains collected in two eras - (i) pre-vaccination with RV1 (1996-February 2006); (ii) post-vaccination (March 2006-2013) - in different Brazilian states were performed. The results showed the Wa-like genomic constellation of the Brazilian G1P[8] strains with a I1-R1-C1-M1-A1-N1-T1-E1-H1 specificity, except for two strains (rj14055-07 and ba19030-10) that belong to a I1-R1-C1-M1-A1-N1-T3-E1-H1 genomic constellation, evidencing the occurrence of reassortment (Wa-like×AU-1-like) of the NSP3 gene. Reassortment events were also demonstrated between Brazilian G1P[8] strains and the RV1 vaccine strain in some genes in vaccinated and unvaccinated children. VP7 and VP8* antigenic site analysis showed that the amino acid substitutions observed in samples collected after the introduction of RV1 in Brazil were already detected in samples collected in the 1980s and 1990s, suggesting that mass Brazilian RV1 vaccination had no impact on the diversity observed inside antigenic sites for these two proteins.
Assuntos
Gastroenterite/virologia , Infecções por Rotavirus/virologia , Vacinas contra Rotavirus/genética , Rotavirus/genética , Vacinação/estatística & dados numéricos , Brasil/epidemiologia , Fezes/virologia , Gastroenterite/epidemiologia , Gastroenterite/prevenção & controle , Variação Genética/genética , Genoma Viral/genética , Genótipo , Humanos , Filogenia , RNA Viral/análise , RNA Viral/genética , Rotavirus/classificação , Rotavirus/imunologia , Infecções por Rotavirus/epidemiologia , Infecções por Rotavirus/prevenção & controle , Vacinas contra Rotavirus/imunologia , Seleção Genética , Vacinas Atenuadas/genética , Vacinas Atenuadas/imunologiaRESUMO
Rotavirus A (RVA) is the most common cause of severe acute gastroenteritis in infants and young children worldwide, causing 453,000 deaths annually. In Brazil, the most frequent genotype identified was G1 during almost three decades in the pre-vaccination period; however, after anti-rotavirus vaccine introduction, there was a predominance of G2 genotype. The aim of this study was to determine the G and P genotypes of rotaviruses isolated from children under 5 years of age with acute gastroenteritis in the Northern region of Brazil, and discuss the emergence of G3P[6] genotype. A total of 783 stool specimens were obtained between January 2011 and March 2012. RVA antigen was detected in 33% (272/783) of samples using a commercial enzyme-linked immunosorbent assay and type-specificity was determined by reverse-transcription polymerase chain reaction. The most common binary combination was G2P[4], representing 41% of cases, followed by G3P[6] (15%), G1P[8] (8%), G3P[8] (4%), G9P[8] (3%), and G12P[6] (2%). G3P[6] strains were analyzed further and phylogenetic analysis of VP7 gene showed that G3 strains clustered into lineage I and showed a high degree of amino acid identity with vaccine strain RV3 (95.1-95.6%). For VP4 sequences, G3P[6] clustered into lineage Ia. It was demonstrated by the first time the emergence of unusual genotype G3P[6] in the Amazon region of Brazil. This genotype shares neither VP7 nor VP4 specificity with the used vaccine and may represent a challenge to vaccination strategies. A continuous monitoring of circulating strains is therefore needed during the post-vaccine era in Brazil.
Assuntos
Infecções por Rotavirus/epidemiologia , Infecções por Rotavirus/virologia , Vacinas contra Rotavirus/administração & dosagem , Rotavirus/classificação , Rotavirus/genética , Antígenos Virais/análise , Brasil/epidemiologia , Proteínas do Capsídeo , Criança , Pré-Escolar , Análise por Conglomerados , Ensaio de Imunoadsorção Enzimática , Fezes/virologia , Feminino , Genótipo , Humanos , Lactente , Recém-Nascido , Masculino , Epidemiologia Molecular , Dados de Sequência Molecular , Filogenia , Prevalência , RNA Viral/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Rotavirus/isolamento & purificação , Infecções por Rotavirus/prevenção & controle , Análise de Sequência de DNARESUMO
Analysis of 27 rotavirus strains from vaccinated and unvaccinated children revealed reassortment events in 3 strains: a gene derived from a vaccine; a gene acquired from a circulating strain; and reassortment between circulating strains. Data suggest that the widespread use of this monovalent rotavirus vaccine may introduce vaccine genes into circulating human rotaviruses or vice versa.
Assuntos
Vírus Reordenados , Infecções por Rotavirus/epidemiologia , Infecções por Rotavirus/virologia , Vacinas contra Rotavirus/efeitos adversos , Rotavirus/genética , Rotavirus/imunologia , Brasil/epidemiologia , Genes Virais , Humanos , Dados de Sequência Molecular , Filogenia , Rotavirus/classificação , Infecções por Rotavirus/prevenção & controle , Vacinas contra Rotavirus/imunologiaRESUMO
In 2009 the World Health Organization recommended the use of group A rotavirus (RVA) vaccines in all national immunization programs (NIPs) in order to control severe RVA gastroenteritis disease. In Brazil, Rotarix™ was introduced in the NIP in March 2006, and a significant reduction in mortality rates among children ≤ 5 years old was observed, especially in the Northern and Northeastern Brazil. In the current study the 11 gene segments of six Brazilian G1P[6] RVA strains, isolated in 2009 and 2010 from vaccinated children, were analyzed in order to investigate if the genetic composition of these strains might help to elucidate why they were able to cause acute gastroenteritis in vaccinated children. All six Brazilian RVA strains revealed a complete Wa-like genotype constellation: G1-P[6]-I1-R1-C1-M1-A1-N1-T1-E1-H1. Phylogenetic analysis showed that all six strains were nearly identical and showed a close genetic relationship with contemporary typical human Wa-like RVA strains. These results suggests that the fact that these strains were able to cause acute gastroenteritis in vaccinated children is likely not due to the genetic background of the strains, but rather to other factors such as host relating factors, co-infecting pathogens or vaccine efficacy. P[6] RVA strains are detected rather occasionally in humans in most regions of the world, except for South Asia and Sub-Saharan Africa. However, recently two studies conducted in Brazil showed the circulation of G12P[6] and G2P[6]. This is the first report on the detection and complete genome analyses of G1P[6] RVA strains in Brazil. Surveillance studies will be crucial to further investigate the prevalence of this genotype in the Brazilian population, and the efficacy of current licensed vaccines, which do not contain the P[6] genotype.
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Infecções por Rotavirus/virologia , Vacinas contra Rotavirus , Rotavirus/classificação , Rotavirus/genética , Brasil/epidemiologia , Pré-Escolar , Fezes/virologia , Genoma Viral/genética , Genótipo , Humanos , Lactente , Filogenia , Rotavirus/isolamento & purificação , Infecções por Rotavirus/epidemiologia , Infecções por Rotavirus/prevenção & controle , Vacinas AtenuadasRESUMO
Rotaviruses are important enteric pathogens for humans and animals. Group A rotaviruses (RV-A) are the most common agents of severe gastroenteritis in infants and young children and vaccination is the most effective method to reduce RV-A-associated diseases. G1P[8], the most prevalent RV-A genotype worldwide, is included in the RV-A vaccine Rotarix®. The discrimination between wild-type G1P[8] and vaccine G1P[8] strains is an important topic in the study of RV-A epidemiology to manage outbreaks and to define control measures for vaccinated children. In this study, we developed a novel method to segregate the wild-type and vaccine strains using restriction endonucleases. The dsRNA from the Rotarix® vaccine was sequenced and the NSP3 gene was selected as the target gene. The vaccine strain has a restriction pattern that is different than that of wild-type RV-A G1P[8] isolates after digestion with the restriction endonuclease BspHI. This pattern could be used as a marker for the differentiation of wild-type G1P[8] strains from the vaccine strain.
Assuntos
Humanos , Fezes , Vacinas contra Rotavirus , Rotavirus , Enzimas de Restrição do DNA , Genótipo , Polimorfismo de Fragmento de Restrição , Infecções por Rotavirus , Rotavirus , Vacinas AtenuadasRESUMO
La infección por rotavirus es la causa más frecuente de diarrea grave en niños costarricenses y del mundo entero, también es la primera causa de muertes por diarrea en niños en países en vías de desarrollo. Existen en la actualidad dos vacunas orales de virus vivos contra el rotavirus disponibles en nuestro país, de amplio uso en varias naciones del mundo, en muchas de las cuales ya han sido incluidas en los esquemas nacionales de vacunación. Una de las vacunas se deriva de una cepa humana atenuada de rotavirus, se administra en un esquema de dos dosis y la otra combina cinco cepas reacomodadas de origen bovinohumano y se administra en un esquema de tres dosis. Ambas vacunas se dan por vía oral y han mostrado tener una elevada eficacia en la prevención de diarrea grave por rotavirus y seguridad con respecto a la posible complicación de intususcepción intestinal. En Costa Rica, se realizan en la actualidad las gestiones necesarias para la inclusión de estas nuevas inmunizaciones en el esquema nacional de vacunación.
Rotavirus is the most common cause of severe diarrhea in Costa Rican children and worldwide, also is the first cause of diarrhea deaths in children in developing countries. Currently, two live oral rotavirus vaccines are available in Costa Rica, they have been used in many countries, in some of them have been included in the national immunization programs. One of these vaccines is derived from an attenuated human strain of rotavirus, is administered in a 2 doses schedule and the other combines five bovine-human reassortant strains and is administered in an schedule of 3 doses. Both vaccines should be given by the oral route. Each vaccine has proven highly effective in preventing severe rotavirus diarrhea in children and safe from the possible complication of intussusception. In Costa Rica, there are currently efforts ongoing to include these new vaccines in the National Immunization Schedule.