Parental perceptions of chickenpox and the varicella vaccine: A qualitative systematic review.

BACKGROUND: In countries where varicella vaccination is not on the routine childhood immunisation schedule, such as those in the United Kingdom (UK), chickenpox is an almost universal disease of childhood. Chickenpox can cause serious complications, particularly in infants, pregnant women, and the immunocompromised. In November 2023 the varicella vaccine was recommended for inclusion in the UK routine childhood immunisation schedule. Successful rollout of the vaccine may be hindered by parental concerns about vaccine safety and efficacy, and perceptions of chickenpox as a mild illness. OBJECTIVE: To examine parental perceptions of chickenpox and varicella vaccination, which may be crucial to effective vaccination campaigns. DESIGN: Qualitative systematic review and thematic analysis. METHODS: Six electronic databases were systematically searched for studies published between 2016 and 2023: CINAHL, EMBASE, MEDLINE, PsycInfo, PubMed, and Web of Science. The included studies were appraised against the Critical Appraisal Skills Program checklist for qualitative studies. Thematic analysis was used to analyse qualitative data, through the development of themes. RESULTS: 22 articles were included in this review, and five themes identified: perceptions that chickenpox is a mild illness, that parents have concerns about varicella vaccine efficacy and safety, a notion of natural immunity as superior, social determinants of health influence vaccine decision making, and vaccination is overwhelming perceived as a parental decision. CONCLUSIONS: Whilst some parents displayed an acceptance and willingness to vaccinate against chickenpox, many expressed concerns, and perceived chickenpox as a routine unworrying childhood illness. Analysis demonstrated a knowledge gap in understanding UK parental opinions regarding chickenpox and varicella vaccination, highlighting the need for research in this area, particularly given ongoing reconsideration for inclusion in the UK vaccination schedule. REGISTRATION: The review was registered on PROSPERO, registration ID CRD42021236120.

Assessing the impact of chickenpox and shingles vaccination using intermittent enhanced surveillance in Queensland, Australia.

INTRODUCTION: Chickenpox and shingles are vaccine preventable diseases caused by varicella-zoster virus (VZV). Chickenpox is more common in children before adolescence and shingles among ≥50 years of age. With this study we aimed to determine changes in VZV epidemiology following chickenpox and shingles vaccine introduction in Queensland. METHODS: This case series study used notified cases of VZV infection in Queensland from January 2010 to December 2021. In Queensland, VZV notifications are received as mostly clinically unspecified cases from pathology laboratories. Intermittent enhanced surveillance was conducted using clinician follow up to determine chickenpox and shingles clinical presentation, and we then analysed these by age-group, time period, and within vaccine eligible cohorts. RESULTS: Of the 87,759 VZV notifications received, 70 % (n = 61,298) were notified as unspecified, followed by 23 % shingles (n = 19,927), and 7 % chickenpox (n = 6,534). Over the study period, the percent change in total notifications adjusted by age and sex was estimated to be an increase of 5.7 % (95 % CI 4.9-6.4) each year. The chickenpox notifications fell sharply at 18 months of age (eligible for chickenpox vaccine) with the rate being 57 % and 36 % lower among those aged 18-23 months compared to <12 and 12-17 months of age, respectively. Assuming all cases aged 60 years and older were shingles, notification rates of shingles decreased by 12-22 % among 70-79 years old (eligible for shingles vaccination) over the years 2017-2021 after vaccine introduction in 2016. CONCLUSION: The VZV notification rate has increased over time in Queensland. Impact of chickenpox and shingles vaccines funded under National Immunisation Program is seen with a decline in notification rates among age-specific cohorts eligible to receive the vaccines under the program. Introduction of a second childhood dose chickenpox vaccine and more effective recombinant shingles vaccine may further improve the impact of the vaccination program.

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

A plain language summary of the impact of vaccines against flu and chickenpox in people with multiple sclerosis treated with cladribine tablets.

WHAT IS THIS SUMMARY ABOUT?: This is a summary of an article originally published in the Multiple Sclerosis Journal. Cladribine tablets (MAVENCLAD®) are an oral (taken by mouth) medication, approved for the treatment of people with relapsing forms of multiple sclerosis (MS, with episodes of new or worsening symptoms). They are administered for a maximum of 10 days per year, over a period of 2 years. Cladribine tablets work by temporarily reducing the number of lymphocytes, which are immune cells that help to fight off infections. Because of this, people with MS (also called PwMS) may have concerns about the effect of cladribine tablets on vaccines, as these work via immune cells to build protection against infection. WHAT HAPPENED IN THE MAGNIFY-MS STUDY?: A study called MAGNIFY-MS investigated how long it takes for cladribine tablets to begin to work in people with a type of MS called highly active relapsing MS. During the study, some participants received their usual vaccinations against flu (influenza) and against the chickenpox virus (also called varicella zoster virus) as part of their routine medical care. The MAGNIFY-MS study gave the researchers an opportunity to look at how cladribine tablets affect the way the flu and chickenpox virus vaccines work in the body. WHAT WERE THE RESULTS?: Cladribine tablets do not affect how well the body responds to flu and chickenpox vaccines. WHAT DO THE RESULTS MEAN?: PwMS taking cladribine tablets who are vaccinated against chickenpox, flu or both can be protected against these diseases.

Current situation and influencing factors of varicella vaccination among left-behind children aged 4-8 years old in Quzhou / 中国学校卫生

Objective@#To understand vaccination coverage and the influencing factors of varicella vaccine (VarV) among left-behind children in Quzhou, which based on protective motivation theory(PMT), so as to provide reference to consolidate VarV vaccination in the next step.@*Methods@#From September to December in 2022, simple random sampling was used to select 628 left-behind children in six counties of Quzhou City. A questionnaire survey on their caregivers was conducted to collect data relating to sociological characteristics and PMT factors, and the influencing factors of VarV were tested by Logistic regression.@*Results@#A total of 628 left-behind children participated in the study. The VarV rate was 69.59%, and 74.83% had received a second dose of VarV. The unvaccinated rate was 30.41%, and caregivers willingness to vaccinate children with VarV was only 10.99%. Logistic regression analysis showed that family relationships, annual household income, number of children in the family, extrinsic rewards and self-efficacy were the influencing factors of VarV among left-behind children ( OR =0.43-3.40， P <0.05). The external reward factor was positively correlated with the vaccination probability ( OR =1.14), and the self-efficacy factor was negatively correlated with the vaccination probability ( OR =0.95).@*Conclusion@#In the context of health education and school promotion, attention should be paid to factors relating to extrinsic rewards and self-efficacy as a means of increasing motivation to seek vaccine protection and improve the use of VarV.

Effectiveness and associated factors of varicella vaccination on school outbreaks / 中国学校卫生

Objective@#To evaluate the effectiveness of varicella vaccine in varicella outbreaks and to analyze the influencing factors, and to provide a reference for making the targeted prevention and controlling measures.@*Methods@#A total of 3 888 students with no history of varicella were selected from 2 schools with varicella outbreak in Guangdong Province in 2021, a retrospective cohort study was conducted by using questionnaire survey, rate ratio ( RR ) and vaccine effectiveness ( VE ) values were calculated and Logistic regression was uses to analyze the factors influencing the protective effect of varicella.@*Results@#There were 138 confirmed cases of varicella among the participants. There was no significant sex difference in the vaccination rate( χ 2=1.36, P =0.51), but there was significant difference in the vaccinattion rate of different age groups( χ 2=555.82, P <0.01). The overall protective effect of VarV was 66.94%(95% CI =56.17%-77.71%), and the protective effect of 2 doses of vaccine( VE = 90.02% , 95% CI =83.13%-96.90%) was higher than that of 1 dose( VE =49.40%, 95% CI =32.36%-66.44%)( χ 2=24.93, P < 0.01 ). The high fever rates in the vaccinated and unvaccinated groups were 7.69% and 25.81%, with significant difference( χ 2= 6.29 , P <0.05). The rates of moderate and severe skin lesions of vaccinated and unvaccinated groups was 20.00% and 50.00%, respectively, and the difference was statistically significant( χ 2=11.32, P <0.01). The protective effects of varicella vaccine against high fever and moderate to severe rash were 70.19%(95% CI =42.11%-98.27%) and 60.00%(95% CI =38.15%-81.85%). Stratified analysis showed that there were significant differences in different years of vaccination( χ 2=37.87, P <0.05), while there were no significant differences in age of vaccination and vaccine manufacturer ( P >0.05).@*Conclusion@#Varicella vaccination can prevent chickenpox infection and reduce the severity of the disease. However, the efficacy of varicella vaccine was affected by vaccination years. It is recommended to improve the vaccination coverage of varicella vaccine to prevent the outbreak of the epidemic.

Epidemiological evaluation for vaccine effectiveness of varicella attenuated live vaccine among students in collective institutions in Jing an District, Shanghai from 2017 to 2019 / 中国学校卫生

Objective@#To understand the vaccination of varicella attenuated live vaccine (VarV) among students in collective institutions, to provide a basis for analying the protective effect of vaccination.@*Methods@#All collective institutions with chickenpox epidemic and post exposure vaccination in Jing an District from 2017 to 2019 were investigated. All students( n =6 473) in the affected class were included. Vaccination status and the incidence information of disease were collected to analyze vaccine effectiveness (VE).@*Results@#The proportion of study subjects without an immunization history decreased year by year, and 7.5% in 2017, 7.2 % in 2018, and 4.9% in 2019. The proportion with a history of one dose prior to exposure in cases was 90.0%, it was lower than 93.5% in the non cases ( χ 2=6.53, P <0.05). The proportion with one dose as post exposure prophylaxis in cases was 8.3%, it was much lower than 44.1% in the non cases ( χ 2=179.06, P <0.01). The proportion with one dose as post exposure prophylaxis in secondary cases was 28.6%, much lower than 44.1% in the non cases ( χ 2=9.44, P <0.01).Unvaccinated ones and the second dose as post exposure prophylaxis ones in cases had the highest rate of varicella development (11.0%), a history of one dose prior to exposure and one dose as post exposure prophylaxis in cases had the lowest varicella rate (1.0%).There was a clear protective effect within two years after one dose of VarV inoculation, VE was 63.1%(95% CI =11.0%-84.7%).@*Conclusion@#The vaccine effectiveness of one dose VarV was limited. Post exposure prophylaxis as early as possible was highly effective in decreasing secondary attack rate.

Where are the vesicles? A case report of Ramsay Hunt syndrome.

A 1-year-10-month-old child developed left-sided Ramsay Hunt syndrome (RHS) without vesicles 1 month after an episode of varicella zoster infection. No ear symptoms, including hearing loss, tinnitus, or imbalance, were reported. The external ear and otoscopic examinations were unremarkable. He achieved adequate recovery with corticosteroid treatment. This case report discusses the unusual presentation of RHS without vesicles, the diagnostic dilemma in young children, varicella zoster virus hepatitis, treatment modalities, and the role of vaccination in its prevention.

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.

Impact of six years of routine varicella vaccination on the disease-related hospitalizations at Minas Gerais, Brazil.

INTRODUCTION: The varicella vaccine was first introduced into the Brazilian immunization schedule in September 2013 as a single dose for children aged 15 months. In 2018, a second dose was recommended for individuals between 4 and 6 years old. This study aims to assess the impact of routine varicella vaccination on the number and profile of hospitalized varicella patients during the single dose period, as well as in the first two years after the adoption of the second dose. METHODS: An observational retrospective study was conducted in an infectious disease pediatric hospital, in Minas Gerais, Brazil. Clinical as well as epidemiological data from patients hospitalized due to varicella between 2010 and 2019 were collected. Patients were split into groups based on the vaccine introduction: pre-vaccine period, single dose and two-dose period. They were compared by age, sex, reason for admission, illness-related complications and clinical outcome. RESULTS: There were 1193 admissions due to varicella during the studied period. When compared with the pre-vaccine period, the number of hospitalizations decreased in 61.5% during the single-dose regime, reaching 95.2% in the two-dose period. Hospitalization rates decreased in all age groups, including non-vaccinated individuals such as those younger than 12 months (92.1%). As for reasons of admission, secondary bacterial skin infections were perceived to be the most common cause (>70%). A reduction was also seen in admission of immunocompromised or HIV positive patients (84.8%). CONCLUSION: The collected data shows a significant impact in the number of hospital admissions due to varicella after six years of the implementation of the vaccine, positively affecting both vaccinated and non-vaccinated individuals. Further reduction was seen after the second dose was initiated, but its true impact will only be understood fully after a longer period of continuous vaccination.

Correlación entre casos de varicela y búsquedas en Google en Perú

Resumen Con el objetivo de determinar la correlación entre los casos de varicela notificados en Perú y las búsquedas sobre varicela realizadas en Google a nivel nacional y por regiones se realizaron análisis de correlación de Spearman para las semanas epidemiológicas del 2016 al 2019, así como antes y después de la introducción de la vacuna para varicela en el Perú. A nivel nacional, se encontró una alta correlación antes del inicio de la vacunación (Rho 0,778, p = 0,001) y moderada durante el periodo de vacunación (Rho 0,441, p = 0,001). Algunas regiones tuvieron una correlación baja o muy baja y dejaron de ser estadísticamente significativas luego de la introducción de la vacuna en el Perú. Además, el cambio en la estacionalidad de la varicela durante el periodo de vacunación también tuvo un impacto en las búsquedas que realiza la población en Google.

Abstract In order to determine if there is a correlation between chickenpox cases reported in Peru and the chickenpox searches carried out on Google at national level and by regions, Spearman's correlation analyzes were carried out for the epidemiological weeks from 2016 to 2019, as well as before and after the introduction of the chickenpox vaccine in Peru. At the national level, a high correlation was found before the start of vaccination (Rho 0.778, p = 0.001) and moderate during the vaccination period (Rho 0.441, p = 0.001), some regions had a low or very low correlation and stopped to be statistically significant after the introduction of the vaccine in Peru. In addition, the change in the seasonality of chickenpox during the vaccination period also had an impact on the searches carried out by the population on Google.

Waning Effectiveness of One-dose Universal Varicella Vaccination in Korea, 2011-2018: a Propensity Score Matched National Population Cohort.

BACKGROUND: Despite high coverage (~98%) of universal varicella vaccination (UVV) in the Republic of Korea since 2005, reduction in the incidence rate of varicella is not obvious. The study aimed to evaluate the vaccine effectiveness (VE) of one-dose UVV by timeline and severity of the disease. METHODS: All children born in Korea in 2011 were included for this retrospective cohort study that analyzed insurance claims data from 2011-2018 and the varicella vaccination records in the immunization registry. Adjusted hazard ratios by Cox proportional hazard models were used to estimate the VE through propensity score matching by the month of birth, sex, healthcare utilization rate, and region. RESULTS: Of the total 421,070 newborns in the 2011 birth cohort, 13,360 were matched for age, sex, healthcare utilization rate, and region by the propensity score matching method. A total of 55,940 (13.29%) children were diagnosed with varicella, with the incidence rate 24.2 per 1000 person-year; 13.4% of vaccinated children and 10.4% of unvaccinated children. The VE of one-dose UVV against any varicella was 86.1% (95% confidence interval [CI], 81.4-89.5) during the first year after vaccination and 49.9% (95% CI, 43.3-55.7) during the 6-year follow-up period since vaccination, resulting in a 7.2% annual decrease of VE. The overall VE for severe varicella was 66.3%. The VE of two-dose compared to one-dose was 73.4% (95% CI, 72.2-74.6). CONCLUSION: We found lower long-term VE in one-dose vaccination and waning of effectiveness over time. Longer follow ups of the vaccinated children as well as appropriately designed studies are needed to establish the optimal strategy in preventing varicella in Korea.

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.

Varicella incidence and vaccination of children in kindergarten and primary school of Longhua District in Shenzhen / 中国学校卫生

Objective@#To understand the situation of varicella prevalence and vaccination of susceptible population in Longhua District，and to provide reference for the varicella immunization program.@*Methods@#A total of 23 706 children from 30 childcare facilities and primary schools in 6 streets were randomly selected throughout the Longhua District. Date on age, grade, recent year and dosage of vaccination, varicella incidence, the overview of vaccination were collected and analyzed.@*Results@#The rate of vaccination in childcare facilities and primary schools was 86.01%, including 55.61% of 1 dose and 30.41% of 2 doses of vaccine. The differences of rate vaccination rate between the childcare facilities and primary schools had statistical significance(χ2=154.95, P<0.05).Rate of no-vaccination,1 dose vaccination and 2 doses vaccination across 6 streets differed significantly(χ2=146.09, 103.93, 127.31, 146.09, P<0.05). There was an increasing positive association between grades and attack rate(χ2=8.65，P<0.05). The differences of attack rate between the childcare facilities and primary schools was of statistical significance(χ2=478.69, P<0.05). The differences of attack rate in street of no vaccination,1 dose vaccination and total attack rate showed statistical significance(χ2=54.49, 74.59, 151.49，P<0.05). There was an increasing linear trend of attack rate of primary school childrenby each year(χ2=24.28，P<0.05). The attack rate increased with time after 1 dose vaccination, immune protection was obtuined for a longer period time after additional doses of vaccine.Negative association was found between grades and protective efficacy rate of varicella. The protective rate and efficacy index of different doses of vaccine in different grades were correlated(r=0.80，0.63，P<0.05). It was most effective after 1 dose vaccination among children in junior grade in kindergarten and 2 dose vaccination in senior grade.@*Conclusion@#After the implementation of vaccination program in Longhua District, the vaccination rate of 2 doses significantly increased, but not for a long time. Varicella vaccine should be included in immunization programme to protect vulnerable populations.

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)

Short-term immunogenicity and safety of hepatitis-A and varicella vaccines in HIV-exposed uninfected and HIV-unexposed South African children.

BACKGROUND: HIV-exposed uninfected (HEU) children have increased risk of infectious morbidity during early childhood. We evaluated the short-term immunogenicity and safety of single dose inactivated hepatitis-A virus (HAV) vaccine and live attenuated varicella zoster virus (VZV) vaccine in South African children. METHODS: 195 HIV-unexposed and 64 HEU children received either one dose of HAV or VZV vaccine at 18 months of age. Blood samples were tested for hepatitis-A or VZV antibodies before and one month after vaccination by chemiluminescent microparticle immunoassay and enzyme-linked immunosorbent assay, respectively. All children were evaluated for solicited adverse events (AEs). RESULTS: One-month post-vaccination, a similar percentage of HIV-unexposed (91.8%) and HEU (82.9%) children were seropositive for hepatitis-A (p = 0.144). VZV antibody geometric mean fold-rise was also similar in HIV-unexposed (5.6; 95%CI: 4.6-6.7) and HEU children (5.1; 95%CI: 3.7-7.2); however, only 44% HIV-unexposed and HEU seroconverted (titers > 50 mIU/ml). AEs occurred with similar frequency and severity between groups, except for more systemic AEs after VZV vaccination in HEU than HIV-unexposed children. CONCLUSIONS: Single dose HAV and VZV vaccine was similarly immunogenic in HIV-unexposed and HEU children. We did not identify differences in short-term humoral immunity after administration of either a live attenuated or inactivated vaccine. Seroconversion rates after a single dose of VZV vaccine were, however, lower compared to reports from previous studies (85-89%). CLINICAL TRIALS REGISTRATION: NCT03330171.

Varicella vaccine dose depended effectiveness and waning among preschool children in Hong Kong.

In Hong Kong, universal varicella vaccination was introduced in July 2014 with a two-dose schedule but the vaccines had been available in the private market since 1996. With data from varicella notification and surveys on immunization coverage, we used the screening method to estimate dose-specific varicella vaccine effectiveness (VE) among preschool children in Hong Kong before universal vaccination. We estimated the VE of one- and two-dose varicella vaccination against all notified varicella as 69.4% (95% confidence interval (95% CI) 69.5-71.2) and 93.4% (95% CI 91.7-94.7), respectively. We found that VE did not decrease with time since receipt. Varicella vaccine was more effective against complications (85.4% [95% CI 48.8-95.8] for one dose and 100% [95% CI -Inf to 100] for two doses) and against hospital admission (75.2% [95% CI 53.4-86.8] for one dose and 93.1% [95% CI 47.1-99.1] for two doses). Lower protection of one-dose varicella vaccine resulted in breakthrough varicella. Under universal vaccination, second-dose varicella vaccine (given as combined measles, mumps, rubella and varicella vaccine) was first scheduled for children when they reach primary one (about 6 years of age) and was recently advanced to 18 months of age. Shortening the interval between the first dose and second dose of varicella vaccination should reduce breakthrough varicella and outbreaks in preschool.

Evaluation of impact of one dose varicella vaccine on the incidence of chickenpox in Argentina.

INTRODUCTION: Varicella, also known as chickenpox is one of the most common immunizable diseases. In 1998, the World Health Organization (WHO) recommended to incorporate this vaccine in the national immunization programs, which Argentina did in 2015. OBJECTIVES: To describe the behavior of the varicella time series for the 2005-2017 period, and to evaluate the impact of the vaccine in Argentina. METHODOLOGY: An ecological observational study was performed, using the varicella cases reported in the National Health Monitoring System, and the data of the National census as secondary data sources. A model based time series analysis of the notified varicella cases in Argentina was performed, using a Negative Binomial Mixed Model. For the verification of the vaccine impact, the 2005-2014 period was selected, and a prognosis for the following years was performed. Impact was evaluated by comparing the rates and confidence intervals between the predicted and observed values. RESULTS: Argentina reported 1,775,587 varicella cases for the 2005-2017 period. The series exhibited seasonality, and, a decreasing trend in the number of cases was observed in 2016 and 2017. A reduction of the incidence rate after the implementation of the vaccine was observed. The transmission risk decreased in the country after vaccine implementation. CONCLUSIONS: This study is the first concrete evidence of the varicella incidence decline after the implementation of a single dose application program in Argentina.