Cobertura y barreras de la vacunación contra la varicela en niños que consultaron a la Fundación Salud Bosque / Coverage of and Barriers to Varicella Vaccination in Children at Fundación Salud Bosque / Cobertura e barreiras à vacinação contra varicela em crianças que consultaram a Fundação Salud Bosque

Introducción. Desde la introducción de la vacuna contra la varicela a Colombia no se ha logrado una cobertura mayor al 90%. El objetivo de este trabajo es identificar las barreras de vacunación contra varicela en niños. Metodología. Estudio descriptivo realizado en la Fundación Salud Bosque; se estudiaron 27 pacientes, 18 hombres (67%) y 9 mujeres (33%), incluyendo menores de 18 años con varicela, y excluyendo pacientes con enfermedades ampollosas distintas a varicela y quemaduras. Se hizo una caracterización demográfica. Para las variables cuantitativas se emplearon promedios y desviación estándar, y para las cualitativas la razón de proporción con Stata V12®. Resultados. La incidencia de varicela fue del 0.2%, solo 9 pacientes (33%) habían recibido la primera dosis de la vacuna, ninguno la segunda dosis. El 92.5% requirió incapacidad; el 89% analgésicos; el 63% antihistamínicos y el 26% antibióticos. Discusión. El estudio realizado demuestra una incidencia significativamente menor en contraste con otras cohortes internacionales. En Colombia no se ha alcanzado la cobertura de la vacunación contra la varicela lograda en Uruguay, Costa Rica, Estados Unidos, Australia, Europa y Taiwán dadas las mismas barreras en su aplicación, mientras que en África no se ha introducido la vacuna contra la varicela porque existen otras prioridades como la desnutrición, la malaria y la infección por Virus de la Inmunodeficiencia Humana. Conclusiones. La cobertura de la vacunación no se ha logrado por barreras modificables que incrementan la incidencia y carga de la enfermedad por costos debido a incapacidad, manejo farmacológico y ausentismo escolar. Palabras clave: Cobertura de Vacunación; Incidencia; Niño; Vacuna contra la Varicela; Varicela.

Introduction. Ever since the introduction of the varicella vaccine in Colombia, coverage has not surpassed 90%. The objective of this work is to identify the barriers to varicella vaccination in children. Methodology. A descriptive study conducted at Fundación Salud Bosque. 27 patients were studied - 18 males (67%) and 9 females (33%) - including children under 18 years of age with varicella, and excluding patients with blistering diseases other than varicella and burns. A demographic characterization was conducted. Averages and standard deviations were used for quantitative variables, and the proportion ratio was used for qualitative variables with Stata V12®. Results. The incidence of varicella was 0.2%. Only 9 patients (33%) had received the first dose of the vaccine, and none had received the second dose. 92.5% required sick leave, 89% required painkillers, 63% required antihistamines, and 26% required antibiotics. Discussion. The conducted study shows a significantly lower incidence compared to other international cohorts. Colombia has not achieved the varicella vaccination coverage of Uruguay, Costa Rica, the United States, Australia, Europe and Taiwan due to the barriers to applying it. Meanwhile, the varicella vaccine has not been introduced in Africa because there are other priorities, such as malnutrition, malaria and the Human Immunodeficiency Virus infection. Conclusions. Vaccination coverage has not been achieved because of modifiable barriers that increase the incidence and burden of the disease due to costs of sick leave, pharmacological treatment and school absenteeism. Keywords: Vaccination Coverage; Incidence; Child; Chickenpox Vaccine; Chikenpox.

Introdução. Desde a introdução da vacina contra varicela na Colômbia, não foi alcançada uma cobertura superior a 90%. O objetivo deste trabalho é identificar as barreiras à vacinação contra varicela em crianças. Metodologia. Estudo descritivo realizado na Fundação Salud Bosque. Foram estudados 27 pacientes, 18 homens (67%) e 9 mulheres (33%), incluindo crianças menores de 18 anos com varicela e excluindo pacientes com outras doenças bolhosas que não varicela e queimaduras. Foi feita uma caracterização demográfica. Média e desvio padrão foram utilizados para as variáveis quantitativas e, para variáveis qualitativas, a razão de proporção com Stata V12®. Resultados. A incidência de varicela foi de 0.2%, apenas 9 pacientes (33%) receberam a primeira dose da vacina, nenhum a segunda dose. 92,5% requeriam atestado; 89% analgésicos; 63% anti-histamínicos e 26% antibióticos. Discussão. O estudo realizado mostra uma incidência significativamente menor em comparação com outras coortes internacionais. A Colômbia não tem atingido a cobertura vacinal contra a varicela alcançada no Uruguai, Costa Rica, Estados Unidos, Austrália, Europa e Taiwan, dadas as mesmas barreiras em sua aplicação, enquanto na África a vacina contra a varicela não foi introduzida porque existem outras prioridades como a desnutrição, a malária e a infecção pelo Vírus da Imunodeficiência Humana. Conclusões. A cobertura vacinal não foi alcançada dadas as barreiras modificáveis que aumentam a incidência e carga da doença devido aos custos por atestados, manejo farmacológico e absenteísmo escolar. Palavras-chave: Cobertura Vacinal; Incidência; Criança; Vacina contra Varicela; Varicela

Reações de hipersensibilidade a vacinas / Hypersensitivity reactions to vaccines

O desenvolvimento e a ampliação do uso das vacinas durante décadas contribuíram para o controle e erradicação de doenças infecciosas, causando um grande impacto na saúde pública no mundo. A análise de segurança das vacinas percorre criteriosos processos e fases dos estudos clínicos, um dos pilares essenciais para aprovação regulatória e utilização do produto na população. O evento supostamente atribuído à vacinação e imunização (ESAVI), terminologia atual, é definido como qualquer ocorrência médica indesejada após a vacinação que possui, ou não, uma relação causal com o uso de uma vacina ou outro imunobiológico. Cabe ressaltar que eventos adversos mais raros ou inesperados, incluindo os eventos de hipersensibilidade, poderão ocorrer na fase pós-comercialização, quando as vacinas são aplicadas em milhões de pessoas. Neste artigo, serão discutidos os principais aspectos relacionados aos eventos adversos de hipersensibilidade pós-vacinais de interesse do especialista, e os desafios frente ao reconhecimento do agente causal e conduta a ser adotada. Além disso, serão revisados os potenciais alérgenos presentes nas vacinas de uso rotineiro para auxiliar o profissional de saúde na identificação de pacientes com potencial de risco de ESAVI por tais componentes. A atualização do conhecimento acerca da segurança e dos benefícios das vacinas pelos profissionais de saúde, sobretudo em populações especiais, contribui para condutas em imunização mais apropriadas, reduzindo o risco de exposição a um possível alérgeno em pessoas comprovadamente alérgicas às vacinas ou a alguns dos seus componentes, além de evitar contraindicações desnecessárias em eventos coincidentes ou não graves.

The expansion of vaccine use and development in recent decades has contributed to the control and eradication of infectious diseases, causing a major impact on public health worldwide. Vaccine safety analysis, which involves careful processes and clinical study, is one of the essential pillars of regulatory approval and use in the population. In current terminology, events supposedly attributable to vaccination and immunization (ESAVI) are defined as any unwanted medical occurrence after vaccination that may or may not have a causal relationship with vaccines or other immunobiologicals. It is noteworthy that rare or unexpected adverse events, including hypersensitivity, can occur during the post-marketing phase, when vaccines are administered to millions of people. In this article, we will discuss the main aspects of post-vaccine hypersensitivity events of interest to specialists and challenges to recognizing the causal agent and appropriate clinical practice. Potential allergens in routine vaccines will also be reviewed to help health professionals identify patients with a potential risk of ESAVI due to such components. Updating health professionals' knowledge about the safety and benefits of vaccines, particularly in special populations, can contribute to more appropriate clinical practice regarding immunization, reducing the risk of exposure to possible allergens in people with allergies to vaccines or their components, avoiding unnecessary contraindications in coincidental or non-serious events.

Genomic structure of varicella-zoster virus and its vaccine application status / 中华预防医学杂志

With the determination of the whole genome sequence of varicella-zoster virus (VZV) virus, the successful breakthrough of infectious cloning technology of VZV, and the emergence of effective preventive vaccines, which have been proven to be effective and safe, varicella has become a disease preventable by specific immunity. This article will review the genomic structure, epidemiological characteristics, and research application progress of varicella vaccine and herpes zoster vaccine of varicella zoster virus to provide reference for primary prevention of the disease.

Comparison of epidemic characteristics and clinical manifestation of chickenpox between adults and children in Shandong Province from 2019 to 2021 / 中华流行病学杂志

Objective: To analyze the differences between adults and children in the epidemic characteristics and clinical manifestations of chickenpox and provide a reference for the prevention strategy adjustment of chickenpox. Methods: The incidence data of chickenpox surveillance in Shandong Province from January 2019 to December 2021 were collected. Descriptive epidemiological methods were used to analyze the distribution of cases, and the chi-square test was used to compare the differences in epidemiological characteristics and clinical manifestations of varicella cases between adults and children. Results: A total of 66 182 cases of chickenpox were reported from 2019 to 2021, including 24 085 cases of adults chickenpox, the male to female sex ratio was 1∶1 (12 032∶12 053), basically the same for men and women, and 42 097 cases of children chickenpox, with a gender ratio of 1.4∶1, the male to female ratio was 1.4∶1 (24 699∶17 398). Fever in chickenpox cases was mainly low and moderate, but the proportion of moderate fever with temperature between 38.1 and 39.0 ℃ in children cases (35.0%,14 744/42 097) was significantly higher than that in adults (32.0%,7 696/24 085). The number of herpes in chickenpox cases was mainly less than 50, but the proportion of severe cases with 100-200 herpes in children was higher than that in adults. The incidence rate of complications was 1.4% (333/24 085) in adults chickenpox, the incidence rate of complications was 1.7% (731/42 097) in children chickenpox. The incidence of encephalitis and pneumonia in children was higher than in adults, and the difference was statistically significant (P<0.05). The proportion of chickenpox cases was mainly outpatient, but the hospitalization rate of children cases was 14.4% (6 049/42 097), higher than that of adults, which was 10.7% (2 585/24 085). Conclusions: There were differences between adult chickenpox and child chickenpox in terms of epidemic and clinical manifestations; the symptoms of child chickenpox were more serious than adult chickenpox. However, the adult chickenpox population is generally susceptible and lacks immune strategy protection, which calls for more attention.

Situação vacinatória da tríplice e da tetra viral em crianças matriculadas na Educação Infantil / The vaccination situation of triple and tetra viral in children enrolled in Early Childhood Education

Objetivo Descrever a situação vacinal de crianças matriculadas nos Centros Municipais de Educação Infantil da Zona Sul do município de Natal, Rio Grande do Norte com relação às vacinas de tríplice e tetra viral. Método Trata-se de um estudo epidemiológico, descritivo e retrospectivo, realizado a partir da análise de cartões de vacina de crianças matriculadas em 15 instituições, nas quais foi possível reunir 773 cartões que foram analisados a partir do calendário básico de vacinação do ano 2015. Os cartões foram classificados em: esquema vacinal completo, incompleto e/ou não vacinado. Resultados Observou-se que 576 (75,51%) crianças estavam com o esquema vacinal completo, sendo o esquema considerado finalizado com a segunda dose da tríplice ou com a tetra viral. A melhor situação vacinal foi atingida nas crianças de dois a quatro anos, com uma cobertura de 84,31%, sendo que 83,3% das crianças dessa faixa etária estavam com o esquema completo e 12,79% das crianças estavam com o esquema vacinal incompleto. Um total de 67 crianças (8,66%) não apresentaram registros de vacina. Com relação à tetra viral, 226 crianças (29,73%) apresentaram esquema vacinal completo. Conclusão Os resultados obtidos no presente estudo revelam uma situação vacinal abaixo da meta estabelecida pelo Programa Nacional de Imunização.

Objective To describe a vaccination situation of children up to 8 years old from the Municipal Centers of Early Childhood Education in the South Zone of the city of Natal, Rio Grande do Norte for vaccines of triple and tetra viral. Method This is an epidemiological, descriptive and retrospective study, carried out based on the analysis of vaccination cards for children from 15 institutions, where it was possible to gather 773 cards, a course based on the basic calendar of the year 2015. They were classified in: complete, incomplete and/or unvaccinated vaccination schedule. Results It is observed that 576 (75.51%) of the children have a complete vaccination schedule, the schedule being completed with a second dose of triple or tetra viral. The best vaccination status was achieved in children aged 2 to 4 years with a coverage of 84.31% and 83.3% children with the complete regimen. We have 12.79% of children with an incomplete vaccination schedule. A total of 67 children (8.66%) who did not have any vaccine records. Regarding Tetra Viral, 226 children (29.73%) had a complete vaccination schedule. Conclusion The results obtained in this study reveal a vaccination situation below the target established by the National Immunization Program.

Prospective observation of breakthrough cases and analysis of antibody dynamic changes after two doses of varicella / 中华预防医学杂志

Objective: To investigate the breakthrough rate and antibody level of children vaccinated two doses varicella vaccine in Tianjin city, and to compare them with those vaccinated one dose. Methods: A total of 1 112 children who were vaccinated two doses varicella vaccine were selected as the experimental group. According to the same street and township, children who had received only one dose within one year of age difference, and whose first injection time was less than one month from the first dose of varicella vaccine in the experimental group were selected as the control group. A three-year prospective observation was conducted on the incidence of varicella in the two groups. 108 pairs of children in the two groups were selected to collect antivaricella serum in the first to third year. The rate of breakthrough cases, antibody level and antibody positive rate were compared by χ2 test, t-test and variance analysis between and within the two groups in three years. Results: The cumulative breakthrough rate of the experimental group was 0.54%(6/1 112), which was lower than that of the control group 3.96% (44/1 112, χ²=29.544, P<0.001). The GMC level of antibody in the experimental group decreased year by year (F=18.291, P<0.001), and the GMC level in the control group also decreased year by year (F=91.383, P<0.001). There was significant difference in GMC level between the two groups (P<0.001). The difference of antibody positive rate in the experimental group was statistically significant in three years (χ²=11.107, P<0.01), there was significant difference in the positive rate between the first year and third year (P<0.01), there was no significant difference in the positive rate of the control group in three years (χ²=3.351, P>0.05). The positive rate of the experimental group was higher than that of the control group (P<0.001). Conclusion: Two doses varicella vaccine can significantly improve the antibody level and positive rate, but it still shows a downward trend with the extension of time. It is necessary to consider strengthening immunization according to the actual situation.

An investigation on serum antibody level of varicella-zoster virus in healthy population in Beijing / 中华预防医学杂志

Objective: To assess the level and trend of varicella-zoster virus (VZV) antibody among healthy population in Beijing in 2017, after the five-year implementation of the two doses varicella vaccination strategy in 2012, and to provide evidence for scientific evaluation of immunization strategy. Methods: A total of 2 144 subjects in ten age groups from 8 districts of Beijing city were recruited in this study using cross-sectional survey based on multi-stage cluster random sampling method. Serum samples were collected and VZV antibody was detected by ELISA. The influencing factors of antibody concentration and positive rate were analyzed and compared with the study in 2012. The antibody concentration and antibody positive rate were analyzed by nonparametric test and χ² test respectively. Results: The ratio of subjects with registered residence in Beijing city to other provinces was 1∶1. The ratio of male to female was 1∶1.08. The median concentration of VZV antibody was 341.4 (78.6, 1 497.8) mIU/ml, and the total antibody positive rate was 71.1% (1 524/2 144). There were significant differences in antibody positive rate (χ²=736.39, P<0.01) and antibody concentration (χ²=740.34, P<0.01) among different age groups. The antibody positive rate generally increased with age (χ²trend=7.32, Ptrend<0.01). Among 862 children under 14 years old, the antibody positive rate of two doses vaccination 72.8% (182/250) was significantly higher than that of one dose vaccination 51.9% (154/297) (χ²=25.14, P<0.01). There was significant difference between 1-4 years old group (χ²=11.71, P<0.01) and 10-14 years old group (χ²=5.95, P=0.02), but not in 5-9 years old group (χ²=3.00, P=0.07). Compared with the study in 2012, the antibody positive rate increased in 5-9 years old group (χ²=14.35, P<0.01) and decreased in 1-4 years old group (χ²=11.51, P=0.01) in 2017. Conclusion: The recommended varicella booster vaccination has significantly improved the VZV antibody level of children in Beijing city. In the future, it is necessary to explore a more optimized two doses varicella vaccination schedule for children in combination with epidemiological evidence.

Caracterización clínica y de costos de la hospitalización asociada a varicela en niños de la Región Metropolitana y de Valparaíso, Chile / Clinical and cost characterization of hospitalization associated with varicella in children from the Metropolitan Region and Valparaíso, Chile

INTRODUCCIÓN: La varicela es una infección relevante en la salud pública de Chile, pudiendo causar en algunas ocasiones complicaciones graves e incluso la muerte, lo que se asocia a un significativo gasto en salud. En Chile sólo se realiza vigilancia centinela a nivel ambulatorio, sin conocerse el impacto de la varicela en casos más graves que determinan hospitalización. OBJETIVOS: Realizar una descripción clínica y de los costos asociados a la atención de niños hospitalizados con diagnóstico de varicela, en años previos a la introducción de la vacuna en el Programa Nacional de Inmunización en Chile. MATERIALES Y MÉTODOS: Estudio multicéntrico, observacional y retrospectivo, en todos los casos de niños hospitalizados (0-15 años) con diagnóstico de varicela, entre enero de 2011 y diciembre de 2015 en cinco hospitales de Chile. Se realizó revisión de fichas para evaluar características clínicas de la enfermedad y los costos asociados a la hospitalización por varicela. RESULTADOS: Un total de 685 hospitalizaciones por varicela fueron incluidas en el estudio. La mediana de edad fue de 3 años (RIC:1-5), siendo la mayoría de los niños con edades comprendidas entre los 1 y 4 años (52% del total de casos). El 56% fueron hombres y sólo 7 niño s (1%) tuvieron antecedente de vacuna varicela. La mediana de días de hospitalización fue de 3 días en cada episodio (RIC: 2-5). El 13% de los casos requirió hospitalización en unidades de mayor complejidad, 7% de los niños ingresó a Unidad de Tratamiento Intensivo y 6% ingresó a Intermedio, ambos con una mediana de 3 días de hospitalización. Las principales complicaciones fueron: infección de piel y tejidos blandos (42%), alteraciones neurológicas (8%) y shock séptico/tóxico (4%). La letalidad fue de 0,4%. El costo de un caso de varicela considerando los costos directos fue de US$417, el costo indirecto fue de US$224 y los costos proporcionales de una muerte de US$3.575. Se estima que el costo total de un caso de varicela hospitalizado en Chile, considerando todos los factores anteriores, fue de US$4.216. CONCLUSIONES: La varicela es una enfermedad inmunoprevenible frecuente. Se observaron casos con una mediana de 3 días de hospitalización por complicaciones, con 13% de los casos requiriendo hospitalización en unidades de mayor complejidad, con un alto costo asociado, que se estima podría disminuir significativamente con la reciente incorporación de la vacuna al Programa Nacional de Inmunizaciones.

BACKGROUND: Varicella is a relevant infection in Chile and may cause serious complications and death, which could be associated with significant health care resource utilization and associated costs. In Chile, sentinel surveillance is carried out only on an outpatient basis, without knowing the impact of varicella in serious cases who need to be hospitalized. AIM: To describe the clinical characteristics and the costs associated with hospitalized children with diagnosis of varicella prior to the vaccine introduction in the National Immunization Program in Chile. PATIENTS AND METHODS: A multicenter, observational, and retrospective study in hospitalized children (0-15 years) with a diagnosis of varicella, were conducted in five hospitals in Chile between January 2011 and December 2015. A review of the clinical records was performed to evaluate the clinical characteristics of the disease and costs associated with hospitalization episodes for varicella. RESULTS: A total of 685 hospitalized children for varicella were included in this study. The median age was 3 years (IQR: 1-5), most children were between 1 and 4 years of age (52% of total cases). 56% were male, and only 7 patients (1%) had a history of previous varicella vaccination. The median lenght of days of hospitalization was 3 days (IQR: 2-5). 13% of the cases required hospitalization in a more complex care unit, 6% in the intermediate unit and 7% in the pediatric intensive treatment unit, both with a median stay of 3 days. The main complications were: skin and soft tissue infections (42%), neurologic (8%) and septic or toxic shock (4%). There were 3 cases of death (0.4%). The direct cost of a varicella case was US $ 417, the indirect cost was US $ 224 and the proportional cost of a case of death was US $ 3,575. It is estimated that the total cost of a hospitalized varicella case in Chile was US $ 4,216. CONCLUSIONS: Varicella is associated with a significant burden of disease in Chile. The median hospital stay was three days with 13% of cases requiring medical care in a complex unit, with high associated costs which could be significantly reduced with the recently incorporation of the varicella vaccine into the National Immunization Program.

Incorporación de segunda dosis de la vacuna de la varicela al Calendario Nacional de Vacunación de Argentina / Incorporation of the second dose of the varicella vaccine to the national vaccination schedule of Argentina

A partir de 2022, a la dosis de vacuna contra la varicela contemplada a los 15 meses de edad en el Calendario Nacional de Vacunación de Argentina, se suma una segunda dosis al ingreso escolar. En este artículo se repasan los aspectos clave para la implementación de esta práctica de inmunización universal, gratuita y obligatoria. (AU)

Starting in 2022, a second dose of the varicella vaccine will be added to the 15-month-old dose included in Argentina's National Vaccination Schedule at school entry. This article reviews the key aspects for the implementation of this universal, free and mandatory immunization practice. (AU)

Number of cases of varicella and hospitalization in a pediatric reference hospital in brazil after introducing the vaccine / Avaliação do número de casos e do perfil de internações por varicela em hospital pediátrico após a introdução da vacina

ABSTRACT Objective: To assess the number of cases and the profile of hospitalizations from varicella after the introduction of the measles, mumps, rubella and varicella combination vaccine in the public health system. Methods: Retrospective study in an infectious diseases pediatric hospital of reference in Southeast Brazil. The cases with a clinical diagnosis of varicella, from January 2011 to June 2016, were assessed from pediatricians' medical records. The hospitalizations were classified into a pre-vaccine group and post-vaccine group, based on the date the vaccine was introduced (September 2013). Both groups were compared by age, sex, time of hospitalization, reason for hospitalization, hospital complications, duration of intensive care, and clinical outcome. Results: A total of 830 hospitalizations were recorded; 543 in the pre-vaccine period and 287 in the post-vaccine period, a reduction of 47.1% (p<0.001). In both periods, a similar profile in the hospitalizations was noticed: majority male; aged between one to five years old; most complications due to secondary causes (mainly skin infections); main outcome was clinical improvement and discharge from the hospital. In the pre-vaccine period, six deaths were recorded and two were recorded in the post-vaccine period. Conclusions: The profile of the hospitalizations was expected to stay the same since this study did not compare vaccinated with unvaccinated children, but hospitalizations before and after the vaccine was introduced. In accordance with the medical literature, we found a significant fall in the number of hospitalizations from varicella.

RESUMO Objetivo: Avaliar o número de casos e o perfil das internações por varicela após a introdução da vacina quádrupla viral na rede pública. Métodos: Estudo retrospectivo conduzido em hospital pediátrico referência em doenças infectocontagiosas na Região Sudeste do Brasil. Foram avaliados os casos com diagnóstico clínico de varicela, registrados em prontuário por médico pediatra, de janeiro de 2011 até junho de 2016. As internações foram classificadas em grupo pré-vacinal e grupo pós-vacinal, com base na data de introdução da vacina (setembro de 2013). Os grupos foram comparados em relação a: faixa etária, sexo, tempo de hospitalização, causas da internação, complicações hospitalares, tempo da internação em terapia intensiva e desfecho clínico. Resultados: Foram documentadas 830 internações, 543 no período pré-vacinal e 287 no pós-vacinal, ocorrendo redução de 47,1% nas internações (p<0,001). Em ambos os períodos, notou-se um perfil similar das internações, predominantemente: sexo masculino; faixa etária de um a cinco anos; por causas secundárias (principalmente infecções de pele); evoluindo com melhora clínica e alta hospitalar. Em relação ao número de óbitos, ocorreram seis no período pré-vacinal e dois no pós-vacinal. Conclusões: A manutenção do perfil das internações era esperada, visto que o trabalho não comparou crianças vacinadas com não vacinadas, e sim internações pré e pós-vacinais. Observou-se, em concordância com a literatura, queda substancial no número de internações por varicela.

Impact of the tetra viral vaccine introduction on varicella morbidity and mortality in the Brazilian macro regions / Impacto da introdução da vacina tetra viral na morbimortalidade por varicela nas macrorregiões brasileiras

Abstract Objective: To describe the impact of the introduction of the viral tetra vaccine in the National Immunization Program in 2013 for 15-month-old children in mortality rates and hospitalization associated with varicella in Brazil. Methods: Mortality rates and hospitalizations rates associated with varicella were evaluated between 2010 and 2016 and described according to Brazilian macro regions and age. The population was stratified into age groups: < 1 year, 1-4 years, and 5-14 years. Data were collected from the Informatics Department of the Unified Health System. A percentage difference was calculated between rates of hospitalizations and mortality in the pre (2010-2012) and post-vaccination periods (2014-2016) to estimate the approximate effectiveness of the vaccine. Data synthesis: At the national level, vaccination significantly reduced the mortality rates and hospitalizations rates in all age groups analyzed. Among those under 5 years of age, mortality rates and hospitalizations rates decreased 57-49% and 40-47%, respectively. There was a national decrease of up to 57% in the mortality rates due to the disease, with smaller decreases seen in the North and Northeast regions and the largest in the South and Southeast regions. The hospitalizations rates for varicella reached a maximum national decline of 47%. In children aged 1-4 years, with higher vaccination coverage, the highest reduction was observed in both mortality rates and hospitalizations rates, which decreased from 2.6 to 0.4/100,000/year. Conclusions: The tetra vaccine proved to be effective in reducing both mortality and hospitalizations of children and adolescents up to 15 years of age in the 2014-2016 triennium.

Resumo Objetivo: Descrever o impacto da introdução da vacina tetra viral no Programa Nacional de Imunização em 2013 para crianças de 15 meses nas taxas de mortalidade e de internação hospitalar associadas à varicela no Brasil. Métodos: As taxas de mortalidade e de internação hospitalar associadas à varicela foram avaliadas entre 2010 e 2016 e descritas conforme macrorregiões brasileiras e idade. A população foi estratificada em grupos etários: < 1 ano; 1-4 e 5-14 anos. Os dados foram coletados do Departamento de Informática do Sistema Unificado de Saúde. Foi realizado um cálculo de diferença percentual entre taxas de internações e mortalidade nos períodos pré (2010-2012) e pós-vacinal (2014-2016) para estimativa de impacto da vacina. Resultados: No nível nacional, a vacinação reduziu significativamente as taxas de mortalidade e de internação hospitalar em todas faixas etárias analisadas. Entre os menores de 5 anos, a taxas de mortalidade e de internação hospitalar diminuíram 57-49% e 40-47%, respectivamente. Houve uma queda nacional de até 57% nos índices de mortalidade pela doença, com menores quedas vistas nas regiões Norte e Nordeste e as maiores nas regiões Sul e Sudeste. As taxas de internação hospitalar por varicela atingiram queda nacional máxima de 47%. Em crianças de 1-4 anos, com maior cobertura vacinal, foi observada a maior redução tanto na taxa de internação hospitalar como na taxa de mortalidade, a qual passou de 2,6 para 0,4/100.000/ano. Conclusões: A vacinação se mostrou efetiva em reduzir tanto mortalidade quanto hospitalizações das crianças e adolescentes de até 15 anos no triênio 2014-2016.

Efectividad preventiva de la vacuna varicela en pacientes sanos no expuestos / Preventive effectiveness of varicella vaccine in healthy unexposed patients

INTRODUCCIÓN: La varicela es una enfermedad infectocontagiosa producida por el virus varicela-zóster. Para su prevención, convencionalmente se utiliza la vacuna varicela, cuya administración busca disminuir la aparición de enfermedad y sus complicaciones. Sin embargo, aún existe controversia sobre la efectividad. MÉTODOS: Realizamos una búsqueda en Epistemonikos, la mayor base de datos de revisiones sistemáticas en salud, la cual es mantenida mediante el cribado de múltiples fuentes de información, incluyendo MEDLINE, EMBASE, Cochrane, entre otras. Extrajimos los datos desde las revisiones identificadas, analizamos los datos de los estudios primarios, realizamos un metanálisis y preparamos una tabla de resumen de los resultados utilizando el método GRADE. RESULTADOS Y CONCLUSIONES: Se identificaron dos revisiones sistemáticas que en conjunto incluyeron 16 estudios primarios, de los cuales, tres corresponden a ensayos aleatorizados. Concluimos que la vacunación contra la varicela disminuye el riesgo de contraer la enfermedad a largo plazo en pacientes sanos sin exposición previa y que probablemente disminuye el riesgo de contraer la enfermedad a corto plazo. Sin embargo, aumenta la reacción local 48 horas posterior a su administración y probablemente aumenta la aparición de fiebre y varicela-like rash.

INTRODUCTION: Chickenpox is an infectious disease caused by varicella-zoster virus. Varicella vaccine is conventionally used for its prevention, and its administration seeks to reduce the onset of the disease and complications associated. However, there is still controversy about its effectiveness. METHODS: We searched in Epistemonikos, the largest database of systematic reviews in health, which is maintained by screening multiple information sources, including MEDLINE, EMBASE, Cochrane, among others. We extracted data from the systematic reviews, reanalyzed data of primary studies, conducted a meta-analysis and generated a summary of findings table using the GRADE approach. RESULTS AND CONCLUSIONS: We identified two systematic reviews including 16 studies overall, of which three were randomized trials. We concluded that the varicella vaccine decreases the risk of contracting the disease in the long term and probably reduces the risk of developing the disease in the short term in healthy unexposed patients. Nevertheless, the vaccination increases the occurrence of local reactions 48 hours after its administration and probably increases the presence of fever and chickenpox-like rash.

Seroprevalence of varicella antibodies in adults without clinical history of disease / Soroprevalência de anticorpos antivaricela em adultos sem história clínica da doença / Seroprevalencia de anticuerpos frente a la varicela en adultos sin historial clínico de la enfermedad

Abstract: Varicella in adults and immunocompromised patients can be severe. The clinical diagnosis of varicella has high accuracy and the history of disease has a high positive predictive value for protection. A significant portion of adults, however, cannot remember if they have had varicella, especially older individuals. We conducted a cross-sectional study to determine the seroprevalence of varicella protective antibodies titers in adults with no clinical history of disease, attended at a Reference Center for Special Immunobiologicals and Travel Medicine in Rio de Janeiro (Brazil). Titration of immunoglobulin G (IgG) antibodies to varicella-zoster was determined by chemiluminescence immunoassay. Among 140 adults without history of varicella, 92% had protective antibody titers. We concluded that seroprevalence of varicella-zoster protection was very high in adults with negative history of disease and the use of serology before vaccination reduced significantly unnecessary vaccine and immunoglobulin use.

Resumo: A varicela é uma doença potencialmente grave em adultos e em pacientes imunocomprometidos. O diagnóstico clínico da varicela apresenta alta acurácia, e o relato da doença na história individual tem alto valor preditivo positivo para a proteção. Entretanto, uma proporção significativa de adultos, principalmente os mais idosos, não se lembra se já teve a doença. Realizamos um estudo transversal para determinar a soroprevalência de títulos protetores de anticorpos contra a varicela em adultos sem história clínica da doença, atendidos em um Centro de Referência para Imunobiológicos Especiais e Medicina de Viagem no Rio de Janeiro, Brasil. Os títulos da imunoglobulina G (IgG) contra varicela-zoster foram determinados por quimiluminescência. Entre 140 adultos sem história de varicela, 92% apresentaram títulos protetores de anticorpos. Concluímos que a soroprevalência de proteção contra varicela-zoster é muito alta em adultos sem história da doença, e que o uso de teste sorológico antes da vacinação reduziria significativamente a vacinação desnecessária e o uso de imunoglobulina.

Resumen: La varicela en adultos y pacientes inmunocomprometidos puede ser grave. El diagnóstico clínico de la varicela tiene una gran precisión y la historia de la enfermedad cuenta con un alto valor predictivo positivo para la protección contra ella. Sin embargo, un porcentaje significativo de adultos, no puede recordar si tuvieron varicela, especialmente las personas más viejas. Realizamos un estudio transversal para determinar la seroprevalencia de las concentraciones de anticuerpos protectores frente a la varicela, en adultos sin historia clínica de la enfermedad, que se llevó a cabo en un Centro de Referencia para Inmunobiología Especial y Medicina del Viajero en Río de Janeiro (Brasil). Se determinó la valoración de los anticuerpos de inmunoglobulina G (IgG) a la varicela-zoster mediante un ensayo inmunológico quimioluminiscente. Entre 140 adultos sin historial de varicela, un 92% tuvieron concentraciones de anticuerpos protectores. Concluimos que la seroprevalencia de la protección a la varicela-zoster fue muy alta en adultos con un historial negativo de la enfermedad y la utilización de la serología antes de la vacunación redujo de manera significativa la vacunación innecesaria y el uso de la inmunoglobulina.

Análisis por series temporales de la incidencia de varicela y el impacto de la implementación de la vacuna en Tucumán / Time series analysis of the chickenpox rate and the impact of vaccine implementation in Tucumán

La varicela es una de las enfermedades inmunoprevenibles más comunes. En 1998 la Organización Mundial de la Salud recomendó incorporar la vacuna a los programas nacionales de vacunación. Argentina lo hizo en 2015. El objetivo de este trabajo fue analizar la serie temporal de varicela durante 2005-2019 y evaluar el impacto de la vacuna sobre su incidencia en Tucumán tras la implementación. MÉTODOS: Se llevó a cabo un estudio observacional de tipo ecológico con fuentes de datos secundarias. Los casos de varicela fueron los consignados por el Sistema Nacional de Vigilancia de Salud. Se describió la serie temporal de casos notificados de varicela para Tucumán y se construyeron modelos aditivos generalizados (GAM) utilizando una distribución binomial negativa. Se verificó el impacto de la vacuna tomando el período 2005-2014, se construyó un modelo GAM y se pronosticó el comportamiento más probable luego de la implementación. Se evaluó el impacto comparando las tasas con sus intervalos de confianza entre lo pronosticado y lo observado. RESULTADOS: Tucumán notificó 82 810 casos durante 2005-2019. La tasa anual varió entre 1,66 por 1000 habitantes (2019) y 6,04 por 1000 habitantes (2007). La serie presentó estacionalidad y en los últimos años una tendencia decreciente. Se observó una disminución significativa de la tasa de incidencia tras la implementación de la vacuna. DISCUSIÓN: El presente trabajo evidenció el impacto de una política pública como la vacuna

Falhas vacinais: avaliando vacinas febre amarela, sarampo, varicela e caxumba / Fallos en vacunas: evaluando vacunas de fiebre amarilla, sarampión, varicela y parotiditis / Vaccine failures: assessing yellow fever, measles, varicella, and mumps vaccines

Resumo: A vacinação é uma das maiores intervenções em saúde pública pela segurança e efetividade, porém nem sempre vacinar significa imunizar. Inúmeros aspectos relacionados tanto ao indivíduo que recebe a vacina, quanto à especificidade de cada imunobiológico administrado compõem o processo para a obtenção de uma adequada imunização, sendo essencial que sejam observados para não culminar em falhas vacinais. A análise dos estudos de imunogenicidade e efetividade para as vacinas sarampo, varicela e caxumba apontam para a necessidade da incorporação de duas doses aos calendários básicos de vacinação para o controle das referidas doenças. Estudos epidemiológicos que analisaram surtos dessas doenças identificaram casos em indivíduos que receberam duas doses da vacina, o que pode apontar provável falha secundária. Para a vacina febre amarela, a discussão atual reside no número de doses ideal para a proteção individual. A Organização Mundial da Saúde recomenda dose única para toda a vida. Apesar dos poucos relatos em literatura a respeito das falhas vacinais, os estudos de imunogenicidade demonstram perda de proteção ao longo dos anos, principalmente na faixa etária pediátrica. Num cenário atual de eliminação e controle de doenças, associado à diminuição da circulação de vírus selvagens, o papel da vigilância epidemiológica é fundamental para aprofundar o conhecimento a respeito dos múltiplos fatores envolvidos, que culminam com falhas vacinais e surgimento de surtos. A ocorrência de surtos de doenças imunopreveníveis impacta negativamente a credibilidade dos programas de imunização, acarretando baixas coberturas vacinais e interferindo no êxito da vacinação.

Resumen: La vacunación es una de las mayores intervenciones en salud pública, por su seguridad y efectividad, sin embargo, no siempre vacunar significa inmunizar. Innumerables aspectos relacionados tanto con el individuo que recibe la vacuna, como con la especificidad de cada inmunobiológico administrado, componen el proceso para conseguir una adecuada inmunización, siendo esencial que sean observados para no acabar con fallos en las vacunas. El análisis de los estudios de inmunogenicidad y efectividad para las vacunas sarampión, varicela y parotiditis, apuntan hacia la necesidad de la incorporación de dos dosis a los calendarios básicos de vacunación para el control de las mencionadas enfermedades. Estudios epidemiológicos que analizaron brotes de esas enfermedades identificaron casos en individuos que recibieron dos dosis de la vacuna, lo que puede apuntar un probable fallo secundario. Para la vacuna de fiebre amarilla la discusión actual reside en el número de dosis ideal para protección individual. La Organización Mundial de la Salud recomienda una dosis única para toda la vida. A pesar de los pocos relatos en la literatura, respecto a los fallos en las vacunas, los estudios de inmunogenicidad demuestran una pérdida de protección a lo largo de los años, principalmente en la franja de etaria pediátrica. En un escenario actual de eliminación y control de enfermedades, asociado a la disminución de la circulación de virus salvajes, el papel de la vigilancia epidemiológica es fundamental para profundizar el conocimiento respecto a los múltiples factores implicados, que culminan con fallos en las vacunas y surgimiento de brotes. La ocurrencia de brotes de enfermedades inmunoprevenibles impacta negativamente en la credibilidad de los programas de inmunización, acarreando bajas coberturas de vacunación e interfiriendo en el éxito de la vacunación.

Abstract: Vaccination is one of the greatest public health interventions, based on its safety and effectiveness, but vaccination does not always mean immunization. Numerous aspects related both to the individual that receives the vaccine and the specificity of each vaccine administered are part of the process of obtaining adequate immunization, and it is essential to observe the aspects in order to avoid vaccine failures. The analysis of immunogenicity and effectiveness studies for the measles, varicella, and mumps vaccines point to the need to incorporate two doses into the basic vaccination calendars in order to control these diseases. Epidemiological studies that analyzed outbreaks of these diseases identified cases in individuals that received two doses of the vaccine, which may indicate likely secondary failure. For the yellow fever vaccine, the current discussion lies in the ideal number of doses for individual protection. The World Health Organization recommends a single dose for life. Despite the few reports in the literature concerning vaccine failures, immunogenicity studies demonstrate waning protection over the years, mainly in the pediatric age bracket. In the current scenario of elimination and control of diseases, associated with the decrease in the circulation of the wild-type viruses, the role of epidemiological surveillance is crucial for expanding knowledge on the multiple factors involved, culminating in vaccine failures and the emergence of outbreaks. Outbreaks of vaccine-preventable diseases negatively impact the credibility of immunization programs, leading to low vaccination coverage rates and interfering in vaccination's success.

Epidemiological Impact of the Korean National Immunization Program on Varicella Incidence

The number of reported varicella cases is continuously increasing in Korea; however, associated medical utilization is declining. The ratio between varicella insurance claims and reports of passive infectious disease surveillance has gradually increased to > 80% since the second half of 2017. The recent increase in reported varicella cases is influenced by improved reporting. We calculated the varicella incidence and cumulative incidence in each birth cohort according to age. The cumulative incidence rate among children aged < 6 years in the birth cohort born after the National Immunization Program introduced the varicella vaccine was about 60% lower than among children born before

Recommended immunization schedule for children and adolescents: Committee on Infectious Diseases of the Korean Pediatric Society, 2018 / 소아과

The Committee on Infectious Diseases of the Korean Pediatric Society recommended immunization schedule for children and adolescents aged 18 years or younger in the 9th (2018) edition of Immunization guideline. This report provides the revised recommendations made by the committee and summarizes several changes from the 2015 guideline. National immunization program (NIP) launched a human papillomavirus (HPV) immunization for girls aged 12 years in 2016. NIP has also expanded age indication for inactivated influenza vaccine (IIV) to 12 years of age in the 2018-2019 season. Quadrivalent IIVs with a full dose (0.5 mL) are approved for all children of 6 months or older. Recommendations of live attenuated influenza vaccine were removed. For inactivated Japanese encephalitis vaccine, first 2 doses are considered as the primary series. Recommendations for use of newly introduced vaccines (diphtheria-tetanus-acellular pertussis/inactivated poliovirus/Haemophilus influenzae type b, 9-valent HPV, new varicella vaccine, new quadrivalent IIV, and attenuated oral typhoid vaccine) were added. Lastly, monitoring system for adverse events following immunization was updated. Other changes can be found in the 9th edition of Immunization guideline in detail.

Humoral immune response to measles and varicella vaccination in former very low birth weight preterm infants

ABSTRACT Introduction: Immune response to vaccination in infants born prematurely may be lower than in infants born at full-term. Some clinical factors might be associated with humoral immune response. Objectives: The objectives of this study were to compare the immune response to measles and varicella vaccination in infants born prematurely with those born at full-term and to analyze factors associated with measles and varicella antibody levels. Methods: Prospective study including two groups of infants aged 12 months. One group of infants born prematurely with birth-weight <1500 g and who were in follow-up at the outpatient clinic for preterm infants at the institution and other group of infants born at full-term. Infants with malformations, primary immunodeficiency diseases, born to HIV-positive mothers or who had received plasma or immunoglobulin transfusions five months before or three weeks after vaccination were excluded. Plasma antibodies were measured by ELISA and factors associated with antibody levels were assessed by linear regression. Results: Sixty-five premature and 56 full-term infants were included. The percentage of immune individuals after vaccination against measles (100% vs. 100%) and varicella (92.5% vs. 93.2%) were similar in both groups, as well as the antibody levels against measles (2.393 vs. 2.412 UI/mL; p = 0.970) and varicella (0.551 vs. 0.399 UI/mL; p = 0.114). Use of antenatal corticosteroids decreased measles antibody levels whereas breastfeeding for more than six months increased varicella antibody levels. Conclusions: Humoral responses to measles and varicella were similar between infants born prematurely and full-term infants. Measles antibody levels were negatively associated with antenatal corticosteroid use; varicella antibodies were positively associated with prolonged breastfeeding.