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.

The impact of varicella vaccination on varicella-related hospitalization rates: global data review / Impacto da vacina varicela nas taxas de internações relacionadas à varicela: revisão de dados mundiais

Abstract Objective: To describe the impact of varicella vaccination on varicella-related hospitalization rates in countries that implemented universal vaccination against the disease. Data source: We identified countries that implemented universal vaccination against varicella at the http://apps.who.int/immunization_monitoring/globalsummary/schedules site of the World Health Organization and selected articles in Pubmed describing the changes (pre/post-vaccination) in the varicella-related hospitalization rates in these countries, using the Keywords "varicella", "vaccination/vaccine" and "children" (or) "hospitalization". Publications in English published between January 1995 and May 2015 were included. Data synthesis: 24 countries with universal vaccination against varicella and 28 articles describing the impact of the vaccine on varicella-associated hospitalizations rates in seven countries were identified. The US had 81.4%–99.2% reduction in hospitalization rates in children younger than four years, 6–14 years after the onset of universal vaccination (1995), with vaccination coverage of 90%; Uruguay: 94% decrease (children aged 1–4 years) in six years, vaccination coverage of 90%; Canada: 93% decrease (age 1–4 years) in 10 years, coverage of 93%; Germany: 62.4% decrease (age 1–4 years) in 8 years, coverage of 78.2%; Australia: 76.8% decrease (age 1–4 years) in 5 years, coverage of 90%; Spain: 83.5% decrease (age <5 years) in four years, coverage of 77.2% and Italy 69.7%–73.8% decrease (general population), coverage of 60%–95%. Conclusions: The publications showed variations in the percentage of decrease in varicella-related hospitalization rates after universal vaccination in the assessed countries; the results probably depend on the time since the implementation of universal vaccination, differences in the studied age group, hospital admission criteria, vaccination coverage and strategy, which does not allow direct comparison between data.

Resumo Objetivo: Descrever o impacto da vacina varicela nas taxas de internações hospitalares associadas à varicela nos países que adotaram a vacinação universal contra a doença. Fontes de dados: Identificaram-se países que adotaram a vacinação universal contra varicela pelo site http://apps.who.int/immunization_monitoring/globalsummary/schedules da Organização Mundial de Saúde e selecionaram-se os artigos no Pubmed que descrevem a variação (pré/pós-vacinal) nas taxas de internações relacionadas à varicela desses países, com auxílio das palavras chaves: "varicella", "vaccination/vaccine" e "children" (ou) "hospitalization". Incluíram-se publicações em inglês entre janeiro de 1995 e maio de 2015. Síntese dos dados: Foram identificados 24 países com vacinação universal contra a varicela e 28 artigos que descrevem o impacto da vacina nas internações associadas à varicela em sete países. Os EUA tiveram 81,4%-99,2% de redução na taxa de internação em crianças menores de quatro anos, após 6-14 anos do início da vacinação universal (1995), com cobertura vacinal de 90%; Uruguai: 94% de queda (crianças de 1-4 anos) em 6 anos, cobertura vacinal de 90%; Canadá: 93% de redução (1-4 anos) em 10 anos, cobertura de 93%; Alemanha: 62,4% de redução (1-4 anos) em 8 anos, cobertura de 78,2%; Austrália: queda de 76,8% (1-4 anos) em 5 anos, cobertura de 90%; Espanha: 83,5% de queda (<5 anos) em 4 anos, cobertura de 77,2%; e Itália: queda entre 69,7%-73,8% (população geral), cobertura de 60%-95%. Conclusões: As publicações revelaram variação no percentual de queda na hospitalização por varicela após a vacinação universal nos países pesquisados; os resultados provavelmente dependem do tempo decorrido após introdução da vacinação universal, diferenças na faixa etária estudada, critérios de internação, cobertura vacinal e estratégia de vacina, não permitindo comparação direta entre os dados.

Epidemiology of Varicella in Korea Based on Pediatrician's Office Practice

PURPOSE: Although varicella outbreakes have frequently occured, the epidemiology of varicella in Korea has not well been delineated. Furthermore without enough investigation with regard to safety and efficacy of varicella vaccine in Korean population, the vaccine has begun to be used in healthy children. Therefore the authors analized the clinical features of patients diagnosed of varicella to aid in understanding the epidemiology of varicella in Korea, and also compared the difference depending on varicella vaccination status. METHODS: The study population consisted of 1154 otherwise healthy patients diagnosed of varicella by six private pediatricians (5 in Seoul and 1 in Incheon) from March 1994 to February 1996. The information pertaining to clinical features of varicella was obtained through questionnaires answered by pediatricians. RESULTS: 1) Among the total 1154 patients, sex ratio was 1.2:1 with male predominance. The average age was 4.1+/-2.5 years old with the range of 1 month to 15 years of age. One thousand and thirty patients (89.2%) were younger than 6 years old and 126 patients (10.9%) were younger than 1 year old. 2) Occurrence of varicella was reported every month during the study period and peak in June, July, and November to January. 3) Two hundreds and eight-four patients (24.6%) had a history of previous varicella vaccination. 4) Four hundreds and fifty-five patients (53.3%) had a history of exposure to patients with varicella and the mean incubation period was 13.7+/-4.1 days with no difference according to varicella vaccination status. 5) Prodromal symptoms were reported from 615 patients (53.3%) with temperature elevation being most frequent. Except for temperature elevation, occurrence of all other prodromal symptoms was not different between unvaccinated and vaccinated patients. 6) Duration of new rash development was 3.9+/-1.3 days with the range of 1 to 9 days and longer in unvaccinated patients (4.1+/-1.2 days) compared to vaccinated patients (3.1+/-1.1 days). Atypical rash was observed in 144 patients (12.5%) and more frequently among unvaccinated patients. 7) Sixty-eight patients suffered from complications which were skin infection (49), conjunctivitis (20), neurologic complication (1), and pneumonia (1), with no difference between unvaccinated and vaccinated patients. CONCLUSIONS: The current study is reporting, for the first time, the epidemiologic features of varicella in Korea. Bedsides, the result of the study, illustrating that 1/4 of the patients reported to have varicella were vaccinated with varicella vaccine, indicates the necessity of the investigation for the safety and efficacy of the vaccine in Korean population.