Dissertations / Theses on the topic 'Chickenpox'

Background Chickenpox is a common infectious disease among children. Ever since a live attenuated vaccine was developed in 1970s, different countries have adopted different vaccination program against chickenpox. Hong Kong recently has commenced a routine childhood varicella vaccination program. The objective of this study is to evaluate whether routine childhood varicella vaccination is cost effective and the implications to Hong Kong. Methodology Literature search was done on electronic databases: Medline and Embase for articles relevant to the topic. A total of 9 articles were retrieved for this systemic review. All 9 studies focus on the cost effectiveness of childhood varicella vaccination with comparison to no vaccination or other interventions. Findings Routine childhood varicella vaccination program is cost effective especially from the societal perspective. The longer the vaccination program takes place, the more cost effective it would be. The cost effectiveness ratio is most sensitive to the coverage rate and the vaccine price. Conclusion It remains unclear whether the routine childhood varicella vaccination program in Hong Kong would be cost effective or not. As the Hong Kong program has adopted the most recent recommendations towards varicella vaccines that the review articles were not included.
published_or_final_version
Public Health
Master
Master of Public Health

Вітряна віспа є однією із найбільш висококонтагіозних інфекцій з переважно повітряно- краплинним механізмом передачі, а також вертикальним та контактним (під час пологів). Збудником вітряної віспи є вірус Varicella-zoster. З вітрянкою пов’язний ризик розвитку ускладнень вітряної віспи у вагітних, виникнення тяжких форм перебігу, патології вагітності, вроджених вад розвитку та захворювань, що визначають перинатальну та малюкову смертність.
Varicella-zoster virus is the cause of chickenpox. The most common mechanism of transmission is air-borne but it is also possible vertical. Susceptibility to Varicella-zoster virus is the total except children in the first two months of age. Chickenpox during pregnancy can cause complications, both for the pregnant woman and the unborn baby. However, the actual risk of any complications occurring is low. Chickenpox is a "children" respiratory infection.

Introdução: A varicela é uma doença exantemática benigna da infância, causada por uma infecção primária pelo vírus Varicela-zoster. No Estado de São Paulo, no ano de 2003, foram notificados 58.972 casos de varicela mediante ocorrências de surtos, configurando um ano hiperendêmico para a doença. De um total de 60 óbitos em todo o Estado, 47 ocorreram em menores de 4 anos. Mais da metade dos óbitos incidiu em moradores da Região Metropolitana da Grande São Paulo. Objetivos: Descrever e caracterizar os indivíduos residentes na Região Metropolitana da Grande São Paulo que evoluíram para gravidade ou óbito por varicela em 2003 e estudar os fatores preditores desses eventos. Métodos: Realizou-se um estudo descritivo das variáveis sociodemográficas, clínicas, antecedentes pessoais e epidemiológicos dos casos de varicela, além de uma análise exploratória dos fatores preditores de gravidade e óbito pela doença. A existência de associação entre as exposições de interesse e gravidade ou óbito por varicela foi investigada pelas estimativas não ajustadas e ajustadas do odds ratio, com os respectivos intervalos de confiança de 95%, utilizando-se a regressão logística não condicional. Resultados: As seguintes variáveis demonstraram associação independente com gravidade e óbito por varicela: complicações raras, pulmonares, hemorrágicas e neurológicas. Cirurgia realizada durante a internação por varicela também foi um fator preditor de gravidade. A taxa de mortalidade foi 36 vezes maior na faixa etária de menores de 15 anos em relação à faixa etária de adultos, e 5 vezes maior na faixa de menores de um ano em comparação à faixa de 1 a 14 anos. Conclusão: O amplo conhecimento da epidemiologia da varicela, suas complicações e fatores de risco para gravidade e óbito, é de extrema importância para fundamentar a implementação de estratégias de prevenção e controle deste agravo nos grupos de maior risco.
Introduction: Chickenpox is a benign exanthematous disease of childhood, whose primary infection is caused by the Varicella-zoster virus. In the State of São Paulo, in 2003, 58,972 chickenpox cases were notified following outbreaks, configuring a hyperendemic year for the disease. From a total of 60 deaths in the whole State, 47 happened in children up to 4 years old. More than half of the deaths occurred in residents of the Greater São Paulo Metropolitan Area. Objectives: To describe and characterize those individuals residents in the Greater São Paulo Metropolitan Area who developed chickenpox severity or death during the year 2003, and to study the predictive factors of these events. Method: A descriptive study was performed, analyzing clinical and social-demographic variables, personal and epidemiological records of the chickenpox cases. Besides, an exploratory analysis of the redictive factors of severity and death by the disease was made. Association between exposures of interest and chickenpox severity or death was investigated by unadjusted and adjusted odds ratio estimation, with 95% confidence intervals, using unconditional logistic regression. Results: The following variables keep an independent association with severity and death for chickenpox: development of rare, pulmonary, hemorrhagic and neurological complications. The need of surgery during the chickenpox hospitalization was an independent predictive factor for severity only. The mortality rate was 36 times greater in the age group from 0 to 14 years old than in the adult age group, and 5 times greater in children up to 1 year old than in the age group ranging from 0 to 14 years old. Conclusion: The comprehensive knowledge of the chickenpox epidemiology, its complications and risk factors for severity and death is extremely important to base the implementation of prevention and control strategies for groups at greater risk of infection.

Many infectious diseases are spread through interactions between susceptible and infectious individuals. Keeping track of where each exposure to the disease took place, when it took place, and which individuals were involved in the exposure can give public health officials important information that they may use to formulate their interventions. Further, knowing which individuals in the population are at the highest risk of becoming infected with the disease may prove to be a useful tool for public health officials trying to curtail the spread of the disease. Epidemiological models are needed to allow epidemiologists to study the population dynamics of transmission of infectious agents and the potential impact of infectious disease control programs. While many agent-based computational epidemiological models exist in the literature, they focus on the spread of disease rather than exposure risk. These models are designed to simulate very large populations, representing individuals as agents, and using random experiments and probabilities in an attempt to more realistically guide the course of the modeled disease outbreak. The work presented in this thesis focuses on tracking exposure risk to chickenpox in an elementary school setting. This setting is chosen due to the high level of detailed information realistically available to school administrators regarding individuals' schedules and movements. Using an agent-based approach, contacts between individuals are tracked and analyzed with respect to both individuals and locations. The results are then analyzed using a combination of tools from computer science and geographic information science.

Вітряна віспа – це гостре інфекційне захворювання, яке спричинюється антропопатогеним вірусом герпесу ІІІ типу – Varicella Zoster Virus, з практично універсальним механізмом передачі – повітряно-краплинним, що забезпечує безперервну циркуляцію вірусу в біосфері Землі. Висока контагіозність, майже 100 % сприйнятливість до цієї інфекції, а також відсутність планової вакцинації не сприяє зменшенню захворюваності. Відносно нетяжкий перебіг, низька летальність були причиною «спокійного» ставлення до цієї хвороби. Але сучасні клінічні спостереження дозволяють стверджувати про появу деяких особливостей перебігу.

Uvod: Varičela (Varicella, Ovčije boginje) i herpes zoster (Herpes Zoster) su bolesti koje izaziva virus varicella - zoster. Varičela spada u najčešće dečje osipne groznice. Herpes zoster je bolest ljudi starijeg životnog doba. Imunizacija protiv varičele i herpes zostera je dala značajne rezultate u prevenciji ovih bolesti. Raspoloživi epidemiološki pokazatelji nisu dovoljni za uvođenje adekvatnog programa imunizacije protiv ovih bolesti u našoj zemlji. Cilj istraživanja bio je da se na teritoriji Vojvodine utvrde: seroprevalencija varicella-zoster virusnih antitela, epidemiološke karakteristike obolelih od varičele u periodu 1994−2014. godine i obolelih od herpes zostera u periodu 1997−2005, uzrasno specifične incidencije i udeo hospitalizovanih u ukupnom broju obolelih od varičele odnosno herpes zostera u periodu 2010−2014. godine. Materijal i metode: Istraživanje epidemioloških karakteristika varičele i herpes zostera je sprovedeno retrospektivno, analizom podataka iz epidemiološkog nadzora. Seroepidemiološko istraživanje je sprovedeno prospektivno (april 2015−februar 2016). Prikupljeno je 3.570 rezidualnih seruma uz prethodno informisanje i pisanu saglasnost pacijenata. Uzorak je reprezentativan za populaciju Vojvodine, prema mestu stanovanja, polu i uzrastu. Imunokompromitovani i primaoci transfuzije krvi u poslednjih šest meseci su izuzeti iz istraživanja. Testiranje seruma je sprovedeno ELISA testom u Centru za virusologiju Instituta za javno zdravlje Vojvodine. Referentna evropska laboratorija prosledila je referentni panel seruma koji je testiran pre i tokom testiranja banke seruma. Standardizacija rezultata je sprovedena na osnovu jednačine koju je prosledio Public Health England (PHE). Izračunata je i analizirana seroprevalencija antitela u odnosu na uzrast, pol i područje stanovanja. Istraživanje incidencije hospitalizovanih slučajeva varičele i herpes zostera sprovedeno je retrospektivno prikupljanjem podataka o hospitalizacijama. Statistički značajnim smatrane su vrednosti na nivou značajnosti p < 0,05 a visoko statički značajnim p < 0,01. Rezultati: Seroprevalencija antitela protiv virusa varicella-zoster u testiranom uzorku populacije Vojvodine je 84%. Utvrđen je očekivano visok procenat seropozitivne dece do navršenih devet godina života (73,3%). Osim u uzrasnim grupama < 1 i 1−4 godine, seroprevalencija raste sa uzrastom. Varičela se u Vojvodini održava endemo-epidemijski sa visokim incidencijama. U posmatranom periodu, najviša uzrasno specifična incidencija varičele se registruje u uzrastu 5−9 godina (5.824,6/100.000 stanovnika) i 0−4 godine (5.000,7/ 100.000 stanovnika). Od varičele su češće obolevali muškaraci dok su žene značajno ćešće obolevale od herpes zostera (p = 0,000 < 0,01). Incidencije varičele i herpes zostera se značajno razlikuju u odnosu na mesto stanovanja. Udeo hospitalizovanih u ukupnom broju obolelih od varičele bio je od 0,7 do 0,9%. Najviša uzrasno specifična incidencija hospitalizovanih sa varičelom registrovana je u uzrastu 0−4 godine i opada sa uzrastom. Incidencija herpes zostera najviša je kod starijih od 60 godina života (970,2/100,000 stanovnika), dok je incidencija hospitalizovanih slučajeva herpes zostera najviša kod starijih od 65 godina (105,7/100.000). Udeo hospitalizovanih slučajeva herpes zostera u ukupnom broju obolelih od herpes zostera se kretao u rasponu od 2,2 do 3,6 % ( ≥2% ). Zaključak: Rezultati ovog istraživanja ukazuju da varičela i herpes zoster značajno opterećuju zdravstveno stanje našeg stanovništva zbog čega postoji osnov za uspostavljanje epidemiološkog nadzora i kreiranje adekvatnog programa imunizacije.
Introduction: Varicella (Varicella, Chicken pox) and herpes zoster (Herpes Zoster) are diseases caused by the Varicella- zoster virus. Varicella is the most common children's rash-causing fever. Herpes zoster is mainly a disease of elderly people. Immunisation against varicella and herpes zoster have led to significant results in the prevention of these diseases. Available epidemiological indicators are not sufficient for introduction of an adequate program of immunization against these diseases in our country. The aim of the research was to establish: seroprevalence of varicella-zoster virus antibodies, the epidemiological characteristics of patients with varicella in the period 1994-2014. and patients with herpes zoster in the period 1997-2005, age-specific incidence and share of hospitalized patients in the total number of patients with varicella and herpes zoster in the period 2010-2014, in Autonomous Province of Vojvodina. Material and methods: The study of epidemiological characteristics of varicella and herpes zoster was conducted retrospectively by analyzing data from epidemiological surveillance. Seroepidemiological study was conducted prospectively (April 2015- February 2016). The total of 3.570 residual sera were collected with previously taken written informed consents of patients. Immunocompromised patients and recipients of blood transfusions in the last six months were not included in the survey. The sample was representative by residence, sex and age for population of Vojvodina. Testing of sera was conducted by ELISA tests at the Center for virusology, Institute of Public Health of Vojvodina. Reference European laboratory forwarded the reference panel serum which was tested before and during the testing of serum bank. Standardization of the results was based on the equation previously sent by Public Health England (PHE). Seroprevalence of antibodies was calculated in relation to the age, sex and area of residence. Incidence of hospitalized cases of varicella and herpes zoster was determined by retrospective collection of hospitalization data. Statistically significant was considered values at a significance level of p < 0,05 and highly statistically significant at p < 0,01. Results: The seroprevalence of antibodies against Varicella- zoster virus in the sample of the population of Vojvodina was 84%. High percentage of seropositive children under the age of nine years of age (73,3%) was determined, as expected. The seroprevalence increases with age, except in the age groups <1 and 1-4. Varicella in Vojvodina maintains endemo-epidemic mode with high incidence. In the observed period, the highest age-specific incidence of varicella is registered in the age group 5-9 years (5.824,6/100.000 inhabitants) and at the age of 0-4 years (5.000,7/100.000 inhabitants). Varicella was found significantly more often in men while herpes zoster was more often in women (p= 0,000 <0,01). Incidence of varicella and herpes zoster significantly varied among the population of certain municipalities in Vojvodina. The share of hospitalized patients in the total number of patients with varicella ranged from 0,7 to 0,9%. The highest age-specific incidence of hospitalized patients with varicella was registered in the age of 0-4 years and decreases with age. The incidence of herpes zoster is highest in people over 60 years of age (970,2/100.000 inhabitants), whereas the incidence of hospitalized cases of herpes zoster was highest in patients over 65 years (105,7/100.000). Proportion of hospitalized cases in the total number of patients with herpes zoster ranged from 2,2 to 3,6% . Conclusion: The results of this study suggest that varicella and herpes zoster are significant burden of the health status of our population and there is a basis for the establishment of epidemiological surveillance and creation of an adequate program of immunization.

Objetivos: Descrever a morbidade associada à varicela em crianças usuárias de creches Municipais de Taubaté e o conhecimento de seus familiares sobre a doença. Casuística e Métodos: Estudo de corte transversal, realizado através de inquérito com responsáveis por 664 crianças que contraíram varicela após admissão às creches. Os responsáveis pelas crianças foram entrevistados por um único examinador, que utilizou um formulário previamente testado. Os dados foram compilados em banco de dados e analisados utilizando o programa Epi-info versão 6.01. Resultados: A varicela acometeu crianças de seis meses a sete anos de idade (mediana = 36 meses) e 8,4% tiveram a doença antes de um ano. Os principais sintomas foram: exantema (100,0%), febre (85,4%), anorexia (39,6%) e cefaléia (15,3%)
Objective: To evaluate the morbidity associated to varicella in day cares centers of Taubaté and the parent's knowledge about the disease. Subjects and Methods: Cross-sectional study, including 664 children that had varicella after admission to the day care centers. Parents of children were interviewed by one of the participant of the study that filled in previously tested form. Data were compiled in database and analyzed in program Epi-info version 6.01. Results: Children had varicella at six months to seven years of age, (median = 36 months) and 8.4% of cases occurred in children under 12 months of age. The most frequent symptoms were: exantema (100.0%), fever (85.4%), anorexia (39.6%) and headache (15.3%). Five hundred and seventeen children (77.9%) were taken for medical visits, 80.6% were medicated, and 73 children (11.0%) were medicated with anti-inflammatory drugs and 52 children (7.8%) with antibiotics

Introdução: Conhecida desde os tempos de Hipócrates, a varicela é autolimitada e isenta de complicações na maioria dos casos, mas responde por absenteísmo escolar das crianças e laboral dos cuidadores, além de hospitalizações e óbitos em pacientes previamente hígidos. Após a incorporação da vacina varicela no calendário americano em 1995, diversos países têm verificado suas epidemiologias para análise de custo-benefício da vacinação; alguns já vêm publicando resultados do impacto da vacina. O Brasil incluiu a vacina no calendário vacinal para crianças de 15 meses em 2013 e vem avaliando o seu impacto. Objetivos: Aprimorar dados pré-vacinais num hospital universitário de atenção secundária, descrevendo atendimentos de Pronto-Socorro Infantil (PSI), hospitalizações e internações em unidade de terapia intensiva (UTI) por varicela; caracterizar o perfil etário, sazonalidade e diagnósticos das complicações da doença, além de analisar possíveis fatores de risco para internação e evolução grave. Metodologia: Estudo retrospectivo descritivo de crianças e adolescentes menores de 15 anos com varicela, no período entre janeiro de 2003 e dezembro de 2012. Relacionamos os resultados à população local para calcular taxas de incidência, hospitalização, internação em UTI e óbito relacionadas à doença. O registro informatizado do hospital forneceu a lista de pacientes com diagnóstico de varicela no atendimento de PSI ou na internação; prontuários foram consultados para coleta de dados que foram submetidos a análise em programas estatísticos. Resultados: Ocorreram 8520 atendimentos em PSI com varicela, 508 destes (6,0%) sendo hospitalizados, 36 destes últimos (7,1%) necessitando de UTI e 2 óbitos (0,4% dos internados), fornecendo as seguintes taxas médias anuais: 887,5 atendimentos, 52,9 hospitalizações, 3,8 internações em UTI e 0,21 óbitos para 100.000 habitantes até 15 anos. Crianças abaixo de 5 anos representaram 75% dos atendimentos, 92,3% das hospitalizações e 88,9% das internações em UTI. Lactentes entre 12 e 15 meses representaram 4,5% dos atendimentos, 6,5% das hospitalizações e 6,1% das internações em UTI. O segundo semestre do ano representou 89,4% dos atendimentos de PSI. Os menores de 5 anos atendidos no PSI tiveram 4,3 vezes maior chance de internação que os maiores de 5 anos, mas a idade não representou diferença no risco para necessidade de UTI. Infecções de pele e partes moles causaram 72,6% das hospitalizações, enquanto problemas respiratórios e neurológicos responderam por 20,1% e 1%, respectivamente. O motivo principal da indicação de UTI foi instabilidade hemodinâmica; 58,3% necessitaram de drogas vasoativas. Comparando os que necessitaram de UTI e os que não necessitaram, os primeiros apresentavam maior tempo de varicela à admissão, febre mais prolongada após internação, maior quantidade absoluta e relativa de neutrófilos e suas formas jovens, Proteína C reativa mais alta e plaquetas reduzidas nos exames admissionais. Conclusão: As taxas epidemiológicas verificadas neste estudo se mostraram dentro do descrito em literatura; as infecções secundárias de pele e partes moles na varicela, sem CID10 específico, prevalecem sobre complicações como pneumopatia, meningite e encefalite, que possuem descritores específicos, como causas de internação e dados de história e exames admissionais podem ajudar a apontar gravidade
Introduction: Known since Hippocrates times, varicella is self-limited and complication-free in most cases, but it responds to school and labor absenteeism of children and caregivers, as well as previously healthy patients hospitalizations and deaths. After varicella vaccine was recommended for routine use in United States in 1995, several countries reviewed their epidemiology for cost-benefit analysis of vaccination; some of then published vaccine impact results. Brazil included varicella vaccine in immunization routine for 15 months child in 2013 and has been appraising its impact. Objectives: Improve pre-vaccination data from secondary care university hospital describing pediatric urgent care (PUC) assessment, inpatient department and pediatric intensive care unit (PICU) hospitalizations; define age profile, seasonality and varicella complications diagnoses and analyze hospitalization and severe evolution possible risk factors. Methods: This report is aimed to retrospectively discriminate children and adolescents under 15 years with varicella from January 2003 to December 2012. Local population was considered to propose varicella-related PUC visit, hospitalization, PICU stay and death rates. Hospital registration provided computerized varicella-diagnosed PUC assessment, inpatient and PICU patient list; data collected from its charts were submitted to statistical program analysis. Results: 8520 PUC varicella cases were reported, 508 of them (6.0%) were hospitalized, 36 of them (7.1%) required PICU and 2 died (0.4% of hospitalized patients), providing following annual rates: 887.5 assessments, 52.9 hospitalizations, 3.8 PICU admissions and 0.21 deaths per 100,000 inhabitants up to 15 years. Children younger than 5 years accounted for 75% of PUC visits, 92.3% of hospitalizations and 88.9% of PICU admissions. Infants between 12 and 15 months represented 4.5% of PUC visits, 6.5% of hospitalizations and 6.1% of PICU admissions. Second half of the year accounted 89.4% of PUC attendances. Under 5 years PUC child had 4.3 more hospitalization risk than those older than 5 years, but age did not represent difference in PICU risk. Skin and soft tissue infections caused 72.6% of hospitalizations, while respiratory and neurological problems accounted for 20.1% and 1%, respectively. The main reason for PICU indication was hemodynamic instability; 58.3% required vasoactive drugs. Comparing those who needed PICU and those who did not need them, the former had longer time of varicella on admission, longer fever after hospitalization, greater absolute and relative amount of neutrophils and their young forms, higher C-reactive protein levels and reduced platelets in admission exams. Conclusion: epidemiological rates verified in this study were within described in literature; secondary skin infections and soft tissues in varicella, without specific ICD-10, overcome complications as pneumopathy, meningitis, and encephalitis, which have specific descriptors; anamnesis and admission examinations data may help predict severity

A infecção é causa de morbimortalidade no paciente com insuficiência renal crônica (IRC), facilitada pela uremia, que leva a resposta imune insuficiente, inclusive após a vacinação. Foram avaliadas a situação vacinal e a presença de anticorpos para sarampo e varicela, de 83 crianças e adolescentes com IRC. A adesão dos pacientes às vacinas foi BCG 100%, poliomielite 98,8%, DPT 97,6%, sarampo monovalente 96,4%, tríplice viral 88%, hepatite B 68,7%. Ausência de anticorpos para sarampo e varicela ocorreu em 14,5% e 26,5% dos pacientes. A susceptibilidade ao sarampo em vacinados, predominou acima de seis anos (P < 0,00001) e à varicela (infecção natural) abaixo de sete anos (P < 0,001). O renal crônico pediátrico deve receber esquema vacinal amplo, com avaliação periódica de títulos de anticorpos
Infections are a cause of morbidity and mortality in chronic renal failure (CRF) patients, facilitated by uremia, which promotes a deficient immune response and hinders response to vaccination. We evaluated the immunization status and antibody titers against measles and varicella in 83 CRF children and adolescents. Adhesion to vaccination was 100% BCG, 98,8% poliomyelitis, 97,6% DPT, 96,4% measles, 88% MMR, 68,7% hepatitis B. Non-detectable antibodies against measles and varicella occurred in 14,5% and 26,5% patients. Susceptibility to measles, after vaccination, increased above 6 years (P < 0,00001) and to varicella (natural infection), below seven years of age (P < 0,001). Pediatric CRF patients should receive a robust immunization program with periodic antibody titer assessment

INTRODUÇÃO: A escolha entre diferentes modelos de análise de decisão introduz variabilidade nos resultados das avaliações econômicas. Modelos estáticos não captam os efeitos indiretos da vacinação comprometendo a avaliação geral dos benefícios da vacinação. Neste trabalho foram desenvolvidos um modelo dinâmico e um modelo estático para a análise de custo-efetividade (ACE) da vacina contra varicela e foram comparados os resultados obtidos com os dois modelos. MÉTODOS: Avaliação econômica completa do tipo ACE usando modelagem. As análises compararam duas estratégias: 1) introdução da vacinação infantil de rotina aos 12 meses de vida; versus 2) situação existente (vacinação após os surtos em creches e vacinação de imunodeprimidos). As análises foram conduzidas no horizonte temporal de 30 anos. RESULTADOS: O modelo dinâmico estimou que na ausência do programa de vacinação ocorreriam 2 915 294 casos de varicela por ano no Brasil, resultando em 879 095 casos ambulatoriais, 4 507 hospitalizações, 119 mortes e 4 casos de sequela. O custo total anual da varicela foi estimado em R$27 378 957 para a sociedade e em R$14 412 610 para o sistema de saúde. A razão de custo-efetividade incremental (RCEI) por ano de vida salvo foi R$14 749 na perspectiva da sociedade e R$16 582 na perspectiva do sistema de saúde. O modelo estático estimou que na ausência do programa de vacinação ocorreriam 1 656 547 casos de varicela por ano no Brasil, resultando em 629 488 casos ambulatoriais, 5 120 hospitalizações, 82 mortes e 1 caso de sequela. O custo total anual da varicela foi estimado em R$17 311 412 para a sociedade e em R$9 570 551 para o sistema de saúde. A RCEI por ano de vida salvo foi R$35 254 na perspectiva da sociedade e R$36 599 na perspectiva do sistema de saúde. Aplicando o limiar de custoefetividade da Organização Mundial de Saúde (OMS) aos resultados obtidos com o modelo dinâmico a vacinação foi considerada uma estratégia custo-efetiva o mesmo não aconteceu com os resultados do modelo estático. Na análise de sensibilidade da taxa de incidência utilizada no modelo estático a RCEI por ano de vida salvo foi R$19 905 na perspectiva da sociedade e R$21 176 na perspectiva do sistema de saúde e a vacinação foi considerada custo-efetiva. CONCLUSÃO: A estimativa de custo-efetividade de programas de vacinação exige o uso de um modelo apropriado. O que é julgado como apropriado será influenciado pelo contexto da avaliação proposta, conhecimento da epidemiologia da doença, disponibilidade de dados e existência de uma equipe qualificada para construir e interpretar os resultados desses modelos.
BACKGROUND: The choice between different decision analysis models introduces variability in the results of economic evaluations. Static models do not take into account the indirect effects of vaccination, thus compromising the overall assessment of vaccination benefits. This work developed two models one dynamic and another static to conduct cost-effectiveness analyses (CEA) of varicella vaccine, comparing the results of the two. METHODS: Comprehensive economic evaluation CEA using modeling. The analysis compared two strategies: 1) introduction of routine vaccination for children under 12 months, versus 2) current situation (vaccination after outbreaks in nurseries and vaccination of immunocompromised). The time horizon of the analysis was 30 years. RESULTS: The dynamic model estimated that in the absence of the vaccination program, 2 915 294 cases of varicella occurred every year in Brazil, resulting in 879,095 outpatient cases, 4,507 hospitalizations, 119 deaths and 4 sequela cases. The total annual cost of varicella was estimated at R$ 27,378,957 for the society and at R$ 14,412,610 for the health care system. From the perspective of society, the incremental cost-effectiveness ratio (ICER) was R$ 14,749 per life-year saved, while from the perspective of the health care system, it amounted to R$ 16,582. The model estimated that, in the absence of a vaccination program, there would be 1,656,547 cases of varicella every year in Brazil, resulting in 629,488 outpatient cases, 5,120 hospitalizations, 82 deaths and 1 case of sequela. The total annual cost of varicella was estimated at R$ 17,311,412 for the society, and at R$ 9,570,551 for the health care system. The ICER was R$ 35,254 and R$ 36,599 from the perspective of society and the health care system, respectively. When applying the World Health Organization (WHO)\'s cost-effectiveness threshold to the dynamic model results, vaccination was considered a cost-effective strategy; this was nevertheless not the case with the static model. In the sensitivity analysis for the incidence rate employed in the static model, the ICER was R$ 19,905 per life-year saved from the perspective of society, and R$ 21,176 from the perspective of the health care system, with vaccination deemed cost-effective. CONCLUSION: Estimating the cost-effectiveness of vaccination programs requires the use of an appropriate model. Establishing an appropriate course of action will depend on the context of proposal evaluation, understanding of disease epidemiology, availability of data, and the existence of a qualified team to build these models and interpret their results.

碩士
國立臺灣大學
流行病學研究所
89
Abstract Backgropund. ─Whether a routine varicella vaccination program is cost-effective has not been fully addressed in Taiwan. Objective.─To perform an economic evaluation to determine whether it is worthwhile to initiate a routine varicella vaccination program for healthy children at age of 15 months old against varicella in Taiwan from health care payer’s perspective and the societal perspective. Methods.─Decision analysis using a mathematical Markov model was conducted to compare the balance between costs and benefit/effectiveness/utility for a routine vaccination program against no vaccination. The vaccine efficacy was relied on published and/or unpublished data. Medical utilization rates and costs were collected from an empirical survey in 4 different districts in Taiwan. Results.─From health care payer’s perspective, the discounted net cost for vaccination program is NT$ 281 millions. The discounted indirect cost saved by vaccination program is estimated at NT$ 733 millions. This yields NT$ 452 millions net saving due to vaccination program from the societal perspective. The marginal cost-effectiveness ratios are calculated as NT$ 1,417, NT$ 249,556, NT$ 46 millions, and NT$ 92 millions for preventing an additional chickenpox case, major complication, death, and long-term disability, respectively, from health payer’s perspective. The marginal cost-utility ratio for the vaccinated group against the unvaccinated group is calculated as NT$ 461 per QALY gained from health care payer’s perspective. The vaccinated group dominates the unvaccinated group from the societal viewpoint. From health care payer’s perspective, a varicella vaccination program can only save NT$ 0.34 in discounted costs for each dollar incurred in a vaccination program whereas save NT$ 2.06 from the societal viewpoint. Conclusions The present study suggests that a routine varicella vaccination program is worthwhile from the societal perspective provided that the vaccine price not beyond NT$2,270

碩士
東海大學
工業工程與經營資訊學系
106
The medical institutions are the high-risk places exposed to infectious diseases. Therefore, the institusions should provide the health care, necessary inspections, follow-up, and prevention measures to their employees. The purpose of this study is to investigate the vaccine antibody titer in the newly recruits of medical institutions and the distribution of antibodies of hepatitis B, varicella, measles and German measles. According to the understanding the vaccine antibody titer of conventional application and the consideration of group immunization, we could establish the referrence of providing additional vaccination policies for newcomers in medical institutions. From January 2016 to April 2017, we collect the database of the health check-ups of new recruits in a medical center in central China. Two hundrend ninty-eight cases were enrolled. We try to find the correlation of the positive rates of hepatitis B, chickenpox, measles, and measles antibodies, gender, age, and the job title. The results showed that the antibody positive rate of hepatitis B, varicella, measles, and German measles were 90%, 86%, 31%, and 68% respectively. On the other hand, using multivariate logistic regression model analysis, age and position are important factors for varicella antibody and hepatitis B antibody. Measles antibodies and German measles antibodies are important factors for each other. We expect to increase the positive rate of antibody in new medical staff and avoid tangible and invisible loss caused by cluster infection.