台灣5歲以下兒童b型嗜血桿菌（Hib）疫苗接種之成本效益分析

Cost-Effectiveness Analysis of Hemophilus influenzae type b (Hib) Vaccination under 5 years of age in Taiwan

佘紫瀅(Tzu-Ying She)

指導教授 ： 譚秀芬

長榮大學/健康科學學院/醫務管理學研究所/碩士(2007年)

https://doi.org/10.6833/CJCU.2007.00103

摘要

B型嗜血桿菌（Hemophilus influenzae type b , Hib）通常好發於5歲以下的幼童，且會引起嚴重的侵襲性疾病，如腦膜炎、肺炎、敗血症、蜂窩組織炎及會厭炎等，其中腦膜炎佔最大比例（52％）且會導致永久性的後遺症甚至死亡。未廣泛疫苗接種前，五歲以下Hib腦膜炎年發生率在美國為每十萬名兒童中有40-60名病例，法國為每十萬人中有28名病例，瑞典為每十萬人中有54名病例，實施全面Hib疫苗接種後，由於疫苗的保護，能有效的預防疾病的發生及減少死亡人數，在美國的成果更是顯著能有效減少Hib的發生率達95％。
而台灣在1997年及2000年的發生率分別為每十萬人中約5.57名及3.22名病患，由於發生率不高，目前一直未將Hib疫苗列為免費疫苗全面注射，但是有部分專家認為Hib發生率有可能被低估，因此本研究的目的在於重新推估2001-2003年0-5歲兒童Hib之流行趨勢，並估計國內Hib疫苗接種實施前後，相關病症之發生情形及醫療成本，進而分析Hib疫苗接種之成本效益。
本研究有兩大主題，分別為疾病發生率的推估以及成本效益分析。我們利用以下三個步驟推估出Hib在台灣的發生率：一、醫學中心病歷分析，二、推估可能受各相關因素影響的比例，包括於檢驗前接受抗生素治療而導致無法驗出菌株、曾否接受菌株培養的比例，三、利用健保資料庫推估全台Hib發生病例數，進而估算出疾病發生率。在成本效益部分，本研究以台灣於92年的出生世代為基礎群體（N=227,070），計算所有幼兒自出生至五歲間接受3劑Hib疫苗所衍生之成本，並以Quality-adjusted life-years(QALYs)作為效益單位，最後與未進行全面接種計畫作成本效益比較，計算Incremental cost effectiveness。
研究結果，2001-2003年0-5歲兒童Hib相關病症發生率分別為每十萬人中有18.01人、24.61人及23.44人。在成本效益部分，實施全面疫苗計畫會比未全面疫苗計畫多付出4.6億元總成本，而效益多13.73個QALY。而成本效益比（CER）分別為未全面疫苗接種計畫5,437,610.30，全面疫苗接種計畫383,617,955.13。增加成本效益比（ICER），以未全面接種計畫為參考組，得出全面接種計畫的ICER值為-3,567,016.03元，亦即是實施疫苗接種計畫比起未接種計畫，雖會減少13.73個QALY lost，但是卻需多花成本3,567,016.03元，遠超過我國平均年生產毛額（約新台幣45萬元），故全面施打Hib疫苗計畫不具經濟效益。

關鍵字

b型嗜血桿菌 ； 疫苗 ； 發生率 ； 成本效益分析

並列摘要

Hemophilus influenzae type b (Hib) usually causes children younger than five years old series invasive diseases such as meningitis, pneumonia, septicemia, cellulitis, and epiglottitis etc. The most common form is meningitis (52%), which leads to severe sequelae and even death in some children. Without the vaccination program, there are approximately 40-60 cases in United States , 28 cases in France and 54 cases in Sweden of meningitis (per 100,000) children aged 0-5 years. However, after the Hib vaccination program, according to the protection of Hib vaccine, the diseases are effectivly prevented. Therefore, much less children are dead. In United States, the incidence of Hib invasive disease has declined by >95%.
There are about 5.57 and 3.22 Hib cases (per 100,000) in Taiwan in years 1997 and 2000 respectively. Due to the low incidence, Taiwan government has no vaccination program of Hib till now. But, some professors indicate that the incidence of Hib may be underestimated. Therefore, the first propose of this thesis is to re-estimate the incidence of Hib among children aged 0-5 years during 2001-2003. Then, evaluate the probability and cost of each situation before and after Hib vaccination program. Finally, analysis the cost-effectiveness of Hib vaccination program.
There are two main objects in our research. One is to estimate the incidence of Hib. The other is to evaluate the cost-effectiveness. We estimate the incidence of Hib in Taiwan by the following three steps: 1. chart review; 2. estimating the real number of Hib cases in 1. under every separating conditions (including the number of Hib cases with and without antibiotic treatment before CSF/Blood culture test and the number of Hib cases whose bacteria had and had not been cultured); 3. evaluating the incidence of Hib by applying the results in 2. into the National Health Insurance Research Database (NHIRD). From the cost-effectiveness analysis (CEA) perspective, we take the birth cohort of years 2003 as the base population (N = 227,070) to estimate the cost of vaccinating 3 doses of Hib vaccine to them and the direct and societal costs of Hib vaccination program among the children during 0 to 5 years old. Besides, we express the effectiveness of vaccination program by the Quality-Adjusted Life-Years (QALYs) and compare the cost-effectiveness between with and without vaccination program. Finally, we also calculate the Incremental Cost Effectiveness (ICE).
As the results, the real numbers of Hib cases among the children during 0 to 5 years old are 18.01, 24.61 and 23.44 (per 100,000) in years 2001, 2002 and 2003 respectively. As the CEA point of view, the government should pay more NT$ 0.46 billion for vaccination program and gain more 13.73 QALYs. The Cost Effectiveness Ratio (CER) of no Hib vaccination program is 5,437,610.30 and that of Hib vaccination program is 383,617,955.13. The Incremental Cost Effectiveness Ratio (ICER) of Hib vaccination program which take no Hib vaccination program as reference is -3,567,016.03. That is to say that although Hib vaccination program reduce 13.73 QALYs lost but spends more NT$ 3,567,016.03. Therefore, Hib vaccination program is non-cost effect in Taiwan.

並列關鍵字

hemophilus influenza type b ； Vaccine ； Incidence ； Cost-effectiveness analysis

參考文獻

文羽苹、許玫玲（2005）。預防保健的成本效益評估：以乳癌篩檢為例。台灣衛誌，24（6），519-528。

行政院衛生署疾病管制局全球資訊網：疫情統計，2005。URL: http://www.cdc.gov.tw。

曾弘富、譚秀芬（2005）。台灣地區b型嗜血桿菌疫苗接種成本效益評估。行政院衛生署疾病管制局九十四年度委託研究計畫。

林奏延、王清虹（1995）。台灣侵襲性流行性感冒嗜血桿菌疾病之流行病學調查。 行政院衛生署八十四年度科技研究發展報告書。

Bijlmer, H. A., & van Alphen, L. (1992). A prospective, population-based study of haemophilous influenzae type b meningitis in the gambia and the possible consequences. J Infect Dis., 165(suppl), S29-S32.