VACCINATION EXTERNALITIES: THE CONCEPT AND APPLICATION IN PHARMACOECONOMIC STUDIES

ABSTRACTObjective: Externalities, could be positive or negative effects, occur in almost all daily life including vaccination activities. This paper aimed to presentsa literature review of the concept of vaccination externalities and its application in pharmacoeconomic/economic evaluation studies.Methods: The literature review was conducted to achieve the study objectives. Searching of literature used MEDLINE electronic database by PubMedinterface as well as Google scholar search engine and employed a number of keywords.Results: There are three most common types of vaccination externalities, namely: Herd immunity, serotype replacement, and antibiotic resistance.Herd immunity gives positive effects to the benefit of vaccination, the opposite of that of serotype replacement; while antibiotic resistance could giveeither positive or negative effects to the benefit of vaccination. Most emergence of serotype replacement occurred after pneumococcal conjugatevaccine vaccination. Most of pharmacoeconomic studies of vaccination used dynamic models to capture vaccination externalities which often includedonly herd immunity effects. Taking herd immunity into account in pharmacoeconomic studies tends to increase the outcomes and reduce the cost;hence, the cost per outcome or incremental cost-effectiveness ratio will decrease, resulting more favorable cost-effectiveness ratio.Conclusions: Vaccination externalities might have effect on the results of pharmacoeconomic studies. Attentiveness should be made to interpret theresults of pharmacoeconomic studies which potentially altered by the effect of vaccination externalities.Keywords: Vaccination externality, Herd immunity, Serotype replacement, Antibiotic resistance, Pharmacoeconomic, Dynamic model

Predicting Treatment Cost for Bacterial Diarrhoeaat a Regional Hospital in Thailand*

The aim of this study was to estimate the treatment cost and formulate a cost-function for bacterial diarrhoea among patients in a Thai regional hospital. This study was an incidence-based cost-of-illness analysis from a hospital perspective, employing a micro-costing approach. It covered new episodes of both outpatients and inpatients who were diagnosed to have bacterial diarrhoea (ICD-10 code A00-A05) and who received treatment during 1 October 2000–31 July 2003. Retrospective data were collected from medical records of the hospital. The study covered 384 episodes, and the mean age of patients was 24 years. The average treatment costs (at 2002 prices; US$1=approximately 40 Thai baht) were US$ 11.29, 76.78, and 44.72 per outpatient episode, inpatient episode, and outpatient/inpatient combined episode respectively. Furthermore, the positive significant predictor variables were: inpatient care, other Salmonella-associated infections, shigellosis, other bacterial intestinal infections, and the health insurance scheme. The fitted model was able to predict greater than 80% of the treatment cost. The estimation of simulated patients demonstrated a wide range of costs, from US$10 per episode to US$ 163 per episode. Overall, hospital administrators can apply these results in cost-containment interventions

Predicting Treatment Cost for Bacterial Diarrhoea at a Regional Hospital in Thailand

The aim of this study was to estimate the treatment cost and formulate a cost-function for bacterial diarrhoea among patients in a Thai regional hospital. This study was an incidence-based cost-of-illness analysis from a hospital perspective, employing a micro-costing approach. It covered new episodes of both outpatients and inpatients who were diagnosed to have bacterial diarrhoea (ICD-10 code A00-A05) and who received treatment during 1 October 2000\u201331 July 2003. Retrospective data were collected from medical records of the hospital. The study covered 384 episodes, and the mean age of patients was 24 years. The average treatment costs (at 2002 prices; US$1=approximately 40 Thai baht) were US$ 11.29, 76.78, and 44.72 per outpatient episode, inpatient episode, and outpatient/inpatient combined episode respectively. Furthermore, the positive significant predictor variables were: inpatient care, other Salmonella -associated infections, shigellosis, other bacterial intestinal infections, and the health insurance scheme. The fitted model was able to predict greater than 80% of the treatment cost. The estimation of simulated patients demonstrated a wide range of costs, from US$10 per episode to US$ 163 per episode. Overall, hospital administrators can apply these results in cost-containment interventions

Treatment Cost for Typhoid Fever at Two Hospitals in Kolkata, India

The purpose of this study was to estimate treatment cost for typhoid fever at two hospitals in Kolkata, India. This study was an incidence-based cost-of-illness analysis from the providers’ perspective. Micro-costing approach was employed for calculating patient-specific data. Unit costs of medical services used in the calculation were directly measured from the study hospital by standard method. The study hospitals were selected based on accessibility to data and cooperation. Eighty-three Widal-positive and/or culture-confirmed patients with typhoid fever during November 2003–April 2006 were included in the study. Most (93%) patients were children. Eighty-one percent was treated at the outpatient department. The average duration of hospitalization for child and adult patients was 8.4 and 4.2 days respectively. The average cost of treating children, adults, and all patients was US$16.72, 72.71, and 20.77 respectively (in 2004 prices). Recalculation based on 80$ 14.53, 36.44, and 16.11 respectively

Economic burden of beta-thalassemia/Hb E and beta-thalassemia major in Thai children

<p>Abstract</p> <p>Background</p> <p>Hemoglobin E beta-thalassemia (β-thalassemia/Hb E) has a variable severity, and the cost of treatment has not been well studied. The aim of this study was to analyze the societal cost of caring for children with β-thalassemias in Thailand. The study was designed as a prevalence-based cost-of-illness analysis in a societal perspective. Medical records from three public hospitals of children aged 2-18 years with β-thalassemia/Hb E and homozygous β-thalassemia were reviewed for direct medical cost determination. For direct non-medical cost and indirect cost, a family member was interviewed.</p> <p>Findings</p> <p>It was found that 201 patients with β-thalassemia/Hb E (91%) and homozygous β-thalassemia (9%) were recruited for this study. Ninety-two (46%) were severe thalassemia and 109 (54%) were mild to moderate severity. The annual average cost of treatment was US$950; 59% was direct medical cost, 17% direct non-medical cost, and 24% indirect cost. The costs were differentiated by some potential predictors. Significant predictor variables were: hospital, health insurance scheme, blood transfusion pattern, and iron chelation drug use.</p> <p>Conclusions</p> <p>The average annual cost per patient was calculated, and the cost model was estimated. These would be applied for national planning, economic evaluation of treatment and prevention interventions, and budget impact analysis.</p

Economic evaluation of rotavirus vaccination:an important step of the introduction to the national immunization program in Thailand

Introduction World Health Organization recommends rotavirus vaccine for all national immunization programs (NIPs). To provide country-specific evidence, we conducted economic evaluation of a monovalent rotavirus vaccination using specific data of the pilot phase in Thailand. Method A Markov model was adopted to compare the 2020 birth cohort once receiving rotavirus vaccination versus no vaccination from healthcare and societal perspective over five years. Data on disease burden, vaccine effectiveness, costs, and utilities were taken from a cohort study in two provinces of Thailand. Sensitivity analyses were performed to test the robustness of the results. Results Rotavirus vaccination would reduce rotavirus diarrhea and costs of illness by 48% and 71%, respectively, over the first five years of life. At USD 13 per dose, vaccine was cost-effective with the ICERs of USD 4,114 and USD 1,571per QALY gained from healthcare and societal perspective, respectively. Results were sensitive to incidence and vaccine cost. The budget for vaccine purchasing was estimated at USD13 million per year. Conclusion Incorporating rotavirus vaccination into the NIP substantially reduced health and cost outcomes and was cost-effective for both perspectives. However, the government needs to negotiate vaccine price prior to program implementation to achieve favorable budget impact

Treatment Costs of Pneumonia, Meningitis, Sepsis, and Other Diseases among Hospitalized Children in Viet Nam

The aim of this study was to estimate the costs of treatment of children who present with the signs and symptoms of invasive bacterial diseases in Khanh Hoa province, Viet Nam. The study was an incidence-based cost-of-illness analysis from the health system perspective. The hospital costs included labour, materials and capital costs, both direct and indirect. Costs were determined for 980 children, with an average age of 12.67 months (standard deviation±11.38), who were enrolled in a prospective surveillance at the Khanh Hoa General Hospital during 2005-2006. Of them, 57% were male. By disease-category, 80% were suspected of having pneumonia, 8% meningitis, 3% very severe disease consistent with pneumococcal sepsis, and 9% other diseases. Treatment costs for suspected pneumonia, meningitis, very severe disease, and other diseases were US$31, US$ 57, US$73, and US$ 24 respectively. Costs ranged from US$24 to US$ 164 across different case-categories. Both type of disease and age of patient had statistically significant effects on treatment costs. The results showed that treatment costs for bacterial diseases in children were considerable and might differ by as much as seven times among invasive pneumococcal diseases. Changes in costs were sensitive to both age of patient and case-category. These cost-of-illness data will be an important component in the overall evidence base to guide the development of vaccine policy in Viet Nam

A Cost Function Analysis of Shigellosis in Thailand

Objective: The purpose of this study was to develop a cost function model to estimate the public treatment cost of shigellosis patients in Thailand. Methods: This study is an incidence-based cost-of-illness analysis from a provider's perspective. The sample cases in this study were shigellosis patients residing in Kaengkhoi District, Saraburi Province, Thailand. All diarrhea patients who came to the health-care centers in Kaengkhoi District, Kaengkhoi District Hospital and Saraburi Regional Hospital during the period covering May 2002 to April 2003 were tested for Shigella spp. The sample for our study included all patients with culture that confirmed the presence of shigellosis. Public treatment cost was defined as the costs incurred by the health-care service facilities arising from individual cases. The cost was calculated based on the number of services that were utilized (clinic visits, hospitalization, pharmaceuticals, and laboratory investigations), as well as the unit cost of the services (material, labor and capital costs). The data were summarized using descriptive statistics. Furthermore, the stepwise multiple regressions were employed to create a cost function, and the uncertainty was tested by a one-way sensitivity analysis of varying discount rate, cost category, and drug prices. Results: Cost estimates were based from 137 episodes of 130 patients. Ninety-four percent of them received treatment as outpatients. One-fifth of the episodes were children aged less than 5 years old. The average public treatment cost was US$8.65 per episode based on 2006 prices (95$1 = 38.084 Thai baht). The majority of the treatment cost (59.3%) was consumed by the hospitalized patients, though they only accounted for 5.8% of all episodes. The sensitivity analysis on the component of costs and drug prices showed a variation in the public treatment cost ranging from US$8.29 to US$9.38 (−4.20% and 8.43% of the base-case, respectively). The public treatment cost model has an adjusted R2 of 0.788. The positive predictor variables were types of services (inpatient and outpatient), types of health-care facilities (health center, district hospital, regional hospital), and insurance schemes (civil servants medical benefit scheme, social security scheme and universal health coverage scheme). Treatment cost was estimated for various scenarios based on the fitted cost model. Conclusion: The average public treatment cost of shigellosis in Thailand was estimated in this study. Service types, health-care facilities, and insurance schemes were the predictors used to predict nearly 80% of the cost. The estimated cost based on the fitted model can be employed for hospital management and health-care planning