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.

Carga económica de la varicela en niños en Perú, entre 2011 y 2016 / Economic Burden of Varicella in Children in Peru from 2011 to 2016

Objetivo: Describir las complicaciones más frecuentes y la carga económica asociada con la varicela en el Perú. Material y métodos: Estudio multicéntrico de revisión de historias clínicas de pacientes de 1 a 14 años con diagnóstico de varicela entre 2011 y 2016. El uso de recursos de atención médica (URAM) asociados con la varicela, los costos unitarios y la pérdida de trabajo se utilizaron para estimar los costos directos e indirectos, presentados en USD ($). Los datos de costos y URAM se combinaron con estimaciones de carga de enfermedad para calcular el costo total anual de la varicela en el Perú. Resultados: Se incluyeron un total de 179 niños con varicela (101 ambulatorios, 78 hospitalizados). Entre los pacientes ambulatorios, el 5,9 % presentó una o más complicaciones, en comparación con 96,2 % de pacientes hospitalizados. El URAM incluyó el uso de medicamentos de venta libre (72,3 % frente a 89,7 % de pacientes ambulatorios y hospitalizados, respectivamente), medicamentos con receta (30,7 % frente a 94,9 %) y análisis y procedimientos (0,0 % frente a 80,8 %). Los costos directos e indirectos por caso ambulatorio fueron $36 y $62 respectivamente y por caso hospitalizado fueron $548 y $222. El costo anual total asociado con la varicela se estimó en $13 907 146. Conclusión: La varicela está asociada con complicaciones clínicas importantes y elevado URAM en Perú, lo que respalda la necesidad de implementación de un plan de vacunación universal. (AU)

Objective: The purpose of this study was to evaluate the clinical and economic burden associated with varicella in Peru. Methods: This was a multicenter, retrospective chart review study of patients aged 1-14 years with a varicella diagnosis between 2011 and 2016. Healthcare resource utilization (HCRU) associated with varicella, unit costs, and work loss were used to estimate direct and indirect costs, presented in USD ($). The cost and HCRU data was combined with estimates of varicella disease burden to estimate the overall annual costs of management of varicella in Peru. Results: A total of 179 children with varicella (101 outpatients, 78 inpatients) were included. Among outpatients, 5.9% experienced ≥1 complication, compared with 96.2% of inpatients. HCRU estimates included use of over-the-counter (OTC) medications (72.3% vs. 89.7% of outpatient and inpatients, respectively), prescription medications (30.7% vs. 94.9%), tests/procedures (0.0% vs. 80.8%). Among outpatients, direct and indirect costs per case were $36 and $62, respectively; among inpatients, respective costs were $548 and $222. The total annual cost associated with varicella was estimated at $ 13 907 146. Conclusion: Varicella is associated with substantial clinical complications and high HCRU in Peru, supporting the need for implementation of a routine childhood varicella vaccination plan. (AU)

Economic burden of varicella in children 1-12 years of age in Argentina, 2009-2014.

BACKGROUND: In Argentina, varicella vaccination was included in the national schedule for mandatory immunizations in 2015. The vaccine has been shown to substantially reduce the morbidity and mortality associated with the virus. The purpose of this study was to evaluate the clinical and economic burden associated with varicella in Argentina prior to vaccine introduction. METHODS: This was a multi-center, retrospective chart review study among patients aged 1-12 years with a primary varicella diagnosis in 2009-2014 in Argentina. Healthcare resource utilization (HCRU) associated with varicella and its complications, unit costs, and work loss were used to estimate direct and indirect costs. All costs are presented in 2015 United States dollars (USD). RESULTS: One hundred and fifty children with varicella were included (75 outpatients, 75 inpatients), with a mean age of 3.8 (SD = 2.4) and 2.9 (SD = 2.2) years, respectively. One or more complications were experienced by 28.0% of outpatients and 98.7% of inpatients, the most common being skin and soft tissue infections, pneumonia, sepsis, cerebellitis, and febrile seizure. HCRU estimates included use of over-the-counter (OTC) medications (58.7% outpatients, 94.7% inpatients), prescription medications (26.7% outpatients, 77.3% inpatients), tests/procedures (13.3% outpatients, 70.7% inpatients), and consultation with allied health professionals (1.3% outpatients, 32.0% inpatients). The average duration of hospital stay was 4.9 (95% CI = 4.2-5.7) days, and the average duration of ICU stay was 4.8 (95% CI = 1.6-14.1) days. The total combined direct and indirect cost per varicella case was 2947.7 USD (inpatients) and 322.7 USD (outpatients). The overall annual cost of varicella in Argentina for children aged ≤14 years in 2015 was estimated at 40,054,378.0 USD. CONCLUSION: The clinical burden of varicella in Argentina was associated with utilization of significant amounts of healthcare resources, resulting in substantial economic costs. These costs should be reduced with the recent implementation of routine vaccination of children.

How cost effective is universal varicella vaccination in developing countries? A case-study from Colombia.

OBJECTIVE: Varicella vaccination has not been introduced worldwide, especially in developing countries. The present study assesses the potential epidemiological and economic impact of one-dose and two-dose varicella vaccination schemes in Colombia, a south American upper middle-income country. METHODS: A decision-tree based model was developed. Varicella cases were estimated based on previous reports of seropositivity within the country. Cost per life-year gained (LYG) was the main outcome measure. Costs from the health care system perspective were expressed in 2008 American dollars. Deterministic and probabilistic sensitivity analyses were performed. RESULTS: In Colombia, there would be 700,197 varicella cases in an average year plus 60 yearly deaths without vaccination. It was estimated that health care costs for all cases during 30 years period could be around US $88,734,735 (with discount). Cost per LYG of one-dose vaccination was US $2519 and using a two-dose scheme was US $5728. CONCLUSION: Vaccinating against varicella in Colombia, an upper middle-income South American country is cost-effective under the assumptions used in this study. Decision-makers should consider introducing universal varicella vaccination in Colombia, given the effectiveness, safety and cost-effectiveness of this intervention.

Incidence and use of resources for chickenpox and herpes zoster in Latin America and the Caribbean--a systematic review and meta-analysis.

BACKGROUND: Varicella-zoster virus causes chickenpox and herpes zoster. More than 90% of varicella cases occur in childhood. The aim of this study was to gather all relevant information on epidemiology and resource use in Latin America and the Caribbean since 2000. METHODS: Epidemiologic studies published since 2000 with at least 50 cases of varicella or herpes zoster, or at least 10 cases of congenital disease were included. Gray literature was also searched. Outcomes included incidence, admission rate, mortality and case-fatality ratio. Use of resources and both direct and indirect costs associated were extracted. RESULTS: From the 495 records identified, 23 were included in the meta-analysis to report varicella-zoster virus outcomes and 3 in the herpes zoster analysis. The global pooled varicella incidence in subjects under 15 years of age was 42.9 cases per 1000 individuals per year (95% confidence interval: 26.9-58.9); children under 5 years of age were the most affected. Pooled general admission rate was 3.5 per 100,000 population (95% confidence interval: 2.9-4.1) and median hospitalization was 5-9 days. The most common varicella complications reported in studies were skin infections (3-61%), followed by respiratory infections (0-15%) and neurologic problems (1-5%). Direct costs averaged (2011/international dollar [I$]) $2040 per admission (range, I$ 298-5369) and I$70 per clinical visit (range, 11-188 I$). CONCLUSIONS: Limited information was available on the outcomes studied. Improvements in the surveillance of ambulatory cases are required to obtain a better epidemiologic picture. As of 2011, only 2 countries introduced the vaccine in national immunization programs in Latin America and the Caribbean.

Costos directos de varicela complicada en una población pediátrica de Colombia / Direct costs of complicated chicken pox in a Colombian pediatric population

Objetivo Estimar los costos directos de varicela en una población pediátrica de Colombia. Método Se diseño un estudio de casos retrospectivo sobre todos los casos de varicela diagnosticados de 2005-2008 en el Hospital Infantil Napoleón Franco Pareja de Cartagena de Indias, Colombia. Fue utilizada la perspectiva del hospital. Se buscaron costos de atención, laboratorio, imagenología y medicamentos. El microcosteo se realizó en pesos colombianos del 2010. Se realizó un ajuste por inflación. Resultados La mediana de costos totales hospitalarios fue de $ 898 766 (Q1: $ 197 348; Q3: $ 1 195 262). La mediana de costo por día hospitalario fue de $ 221 777 (Q1: $ 97 027; Q3: $ 293 740). En menores de 1 año la mediana de costo fue de $ 980 742 (Q1: $ 905 708; Q3: $ 1 026 031). En pacientes de 5-12 años la mediana de costo fue de $ 105 833 (Q1: $ 39 568; Q3: $ 891 824). Conclusiones. Los resultados se asemejan con estudios previos sobre el tema (en Panamá, e incluso algunos países desarrollados), evidenciando un relativo alto costo de enfermedad por varicela en Colombia. Estos resultados aumentan la evidencia a favor de la vacunación, e invitan a decisores en salud en Colombia a considerar la introducción de la vacunación contra varicela.

Objective Estimating the cost of chicken pox in a Colombian pediatric population. Methodology This was a retrospective case study which searched for all diagnosed chicken pox cases in the Napoleón Franco Pareja children’s hospital (Cartagena, Colombia), during 2005-2008. The hospital’s records/perspective was used. Cost related to health personnel, lab, diagnostic images and drugs were searched. The micro-costing was made at Colombian peso prices for 2010. An adjustment was made for inflation. Results Mean hospital costs were $ 898,766 (Q1: $ 197,348; Q3: $ 1,195,262). Mean hospital cost per day was $ 221,777 (Q1: $ 97,027; Q3: $ 293,740). Mean cost <1 year-old patients was $ 980,742 (Q1: $ 905,708; Q3: $ 1,026,031). Mean cost was $ 105,833 in 5-12 year-old patients (Q1: $ 39,568; Q3: $ 891,824). Conclusions The results were similar to those of previous studies (in Panama and some developed countries) highlighting relatively high illness costs in Colombia. These results increase the evidence in favor of vaccination and invite Colombian public health officials to consider introducing a chicken pox vaccine into Colombia.

[Direct costs of complicated chicken pox in a Colombian pediatric population]. / Costos directos de varicela complicada en una población pediátrica de Colombia.

OBJECTIVE: Estimating the cost of chicken pox in a Colombian pediatric population. METHODOLOGY: This was a retrospective case study which searched for all diagnosed chicken pox cases in the Napoleón Franco Pareja children's hospital (Cartagena, Colombia), during 2005-2008. The hospital's records/perspective was used. Cost related to health personnel, lab, diagnostic images and drugs were searched. The micro-costing was made at Colombian peso prices for 2010. An adjustment was made for inflation. RESULTS: Mean hospital costs were $ 898,766 (Q1: $ 197,348; Q3: $ 1,195,262). Mean hospital cost per day was $ 221,777 (Q1: $ 97,027; Q3: $ 293,740). Mean cost <1 year-old patients was $ 980,742 (Q1: $ 905,708; Q3: $ 1,026,031). Mean cost was $ 105,833 in 5-12 year-old patients (Q1: $ 39,568; Q3: $ 891,824). CONCLUSIONS: The results were similar to those of previous studies (in Panama and some developed countries) highlighting relatively high illness costs in Colombia. These results increase the evidence in favor of vaccination and invite Colombian public health officials to consider introducing a chicken pox vaccine into Colombia.

Prophylaxis against respiratory syncytial virus (RSV), varicella, and pneumococcal infections: Economic-based decision-making.

OBJECTIVE: To compare costs and health benefits of three prophylactic interventions recommended by the American Academy of Pediatrics (AAP) and to help quantify the impact of illness and enhance the physicians' ability to make informed decisions. STUDY DESIGN: Medline search was conducted of English-language cost-effectiveness studies of varicella and pneumococcal conjugate vaccination recommended for all healthy infants and of respiratory syncytial virus (RSV) prophylaxis with palivizumab (Synagis) for infants at high risk for severe RSV infection. Data were collected on cost-effectiveness, burden of illness, and efficacy and analyzed from the societal and payer perspective. Results were discounted by 5% and costs inflated to year 2002 dollars. RESULTS: From the societal perspective, estimates of cost per life-years saved were money savings for varicella, 175,300 US dollars for pneumococcal conjugate vaccination, and 66,200 US dollars for palivizumab prophylaxis; from the payer perspective, estimates were 28,100, 338,400, and 66,400 US dollars, respectively. CONCLUSIONS: Cost-effectiveness estimates for varicella and pneumococcal conjugate vaccination demonstrate that evaluating economic benefits from the societal rather than the payer perspective makes universal prophylaxis very financially attractive. By comparison, this same differential does not exist for the cost-effectiveness estimates of palivizumab from the societal and payer perspectives because its use is in a well-defined high-risk target population. From a societal perspective, prophylaxis is a rational public policy decision, although in target populations, incidence of serious illness and the primary cost components driving the cost offsets vary across prophylactic measures studied.

[Complications in children with varicella in 4 hospitals in Santiago, Chile: clinical spectrum and estimation of direct costs]. / Complicaciones en niños con varicela en cuatro hospitales de Santiago-Chile: espectro clínico y estimación de costos directos.

BACKGROUND: The knowledge of varicella complications and their associated cost may help for a better evaluation of varicella immunization benefits. AIM: To determine frequency, type, outcome and affected population of varicella complications in children requiring hospitalization, and to estimate their direct costs. MATERIAL AND METHODS: Retrospective analysis of medical records of children admitted to four hospitals in Santiago, Chile, due to varicella complications between January 1997 and February 1999. Calculation of direct costs of hospitalizations in a sample of 30 patients. RESULTS: One hundred fifty four patients were identified, 74% were younger than 5 years old, only one was immunocompromised. Complications identified were skin and soft tissue infections in 63%, invasive infections in 25.3%, neurological in 7.1% and miscellaneous in 4.5%. Staphylococcus aureus and Group A beta-haemolytic Streptococcus (GABS) were predominantly isolated. S. aureus was the main agent identified in superficial infections and GABS in invasive infections (sterile sites). Two patients died due to invasive infections (streptococcal toxic shock and S. aureus septicaemia) and 11 required surgical procedures. The average cost per hospitalization was US$ 600 in public hospitals and US$ 1,800 in the private hospital. CONCLUSIONS: Varicella complications requiring hospitalization are due mainly to bacterial infections and they affect immunocompetent toddlers. These complications can be severe and even fatal.

Community impact of childhood varicella infections.

OBJECTIVES: To assess age-specific incidence rates, health care utilization, and lost parental work associated with varicella infection in a population-based cohort of children, and to validate parent-reported health care utilization data. STUDY DESIGN: We conducted a telephone survey of a population-based cohort of 4557 households with children aged birth to 13 years. Medical chart abstraction was used to validate health care utilization information. RESULTS: We report varicella incidence rates in preschool children that are 2 to 2.5 times higher than previous studies. Rates of varicella-related serious complications, hospitalizations, parental work leave, and medication use are comparable with rates reported elsewhere. However, health provider visits occurred only 0.3 to 0.5 times as frequently as estimated in other studies. One hundred percent of reported hospitalizations and serious complications and 92% of provider visits were validated to be within the study time frame through medical chart audits. CONCLUSIONS: Parents are an accurate source of varicella-related health care utilization data. Parent-reported incidence data indicate that varicella infections are increasing in preschool children. This shift to infections in younger children may be related to the increased use of out-of-home care for infants and young children. Furthermore, the shift may after the community burden of varicella because of the observed increased parental work loss and decreased frequency of health care visits in the preschool children.

Childhood vaccination against chickenpox: an analysis of benefits and costs.

OBJECTIVE: To estimate the economic costs and benefits of routine childhood vaccination against varicella infection. DESIGN: Decision-analytic model of the incidence and costs of chickenpox in children assumed to receive varicella vaccine at age 15 months in conjunction with the measles-mumps-rubella vaccine, or not to be vaccinated against varicella. PATIENTS: Hypothetical cohort of 100,000 children. MAIN OUTCOME MEASURES: Costs of vaccination, cumulative incidence of chickenpox to age 25 years, and related disease costs, including medical treatment and work loss. RESULTS: Vaccination of 100,000 children against varicella at age 15 months would cost $4,812,000. The expected number of cases of chickenpox to age 25 years would be reduced from 95,400 to 4800; costs of medical treatment and work loss would correspondingly decline by $1,678,000 and $9,781,000, respectively. On balance, vaccination is estimated to yield net economic benefits of $6,647,000, or $66.47 per vaccinee. CONCLUSION: Vaccination against varicella infection is cost-effective and should be part of the routine immunization schedule for U.S. children.

Fundamentos de la introducción de la vacuna contra la varicela / Fundamentals of the introduction of the varicella vaccine

La Varicela es una enfermedad infectocontagiosa. Es la enfermedad exantemática mas frecuente de la infancia. Se estima que se producen 40000 casos nuevos cada año en Argentina, los cuales se presentan habitualmente en la primera década de vida. Aunque no suele ser considerada un problema prioritario de salud publica, las consecuencias y el impacto socioeconómico de esta enfermedad que afecta prácticamente a todos los niños y que es motivo de ausentismo escolar y laboral, no deben ser subestimados. Es una causa frecuente de consulta médica e internación y en caso de afectar a personas de alto riesgo genera mayor morbilidad. La vacuna contra VVZ es una herramienta importante para reducir en forma significativa la carga de enfermedad y la morbimortalidad por complicaciones o formas graves de presentación, especialmente en poblaciones de riesgo