Department of Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, London, UK
Department of Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, London, UK.
BMJ Glob Health. 2024 Nov 18;9(11):e015837. doi: 10.1136/bmjgh-2024-015837.
Thailand was one of the first low- and middle-income countries to publicly fund seasonal influenza vaccines, but the lack of predictability in the timing of epidemics and difficulty in predicting the dominant influenza subtypes present a challenge for existing vaccines. Next-generation influenza vaccines (NGIVs) are being developed with the dual aims of broadening the strain coverage and conferring longer-lasting immunity. However, there are no economic evaluations of NGIVs in Thailand.
We estimated the health impact and cost-effectiveness of NGIVs in Thailand between 2005 and 2009 using a combined epidemiological and economic model. We fitted the model to data on laboratory-confirmed influenza cases and then simulated the number of influenza infections, symptomatic cases, hospitalisations and deaths under different vaccination scenarios based on WHO-preferred product characteristics for NGIVs. We used previous estimates of costs and disability adjusted life years (DALYs) for influenza health outcomes to estimate incremental net monetary benefit, vaccine threshold prices and budget impact.
With the current vaccine programme, there were an estimated 61 million influenza infections. Increasing coverage to 50% using improved vaccines reduced infections to between 23 and 57 million, and with universal vaccines to between 21 and 49 million, depending on the age groups targeted. Depending on the comparator, threshold prices for NGIVs ranged from US$2.80 to US$12.90 per dose for minimally improved vaccines and US$24.60 to US$69.90 for universal vaccines.
Influenza immunisation programmes using NGIVs are anticipated to provide considerable health benefits and be cost-effective in Thailand. However, although NGIVs might even be cost-saving in the long run, there could be significant budget implications for the Thai government even if the vaccines can be procured at a substantial discount to the maximum threshold price.
泰国是最早将季节性流感疫苗纳入公共资助范围的中低收入国家之一，但由于流行时间难以预测，且难以预测优势流感亚型，这给现有疫苗带来了挑战。正在开发下一代流感疫苗（NGIV），其双重目标是扩大菌株覆盖范围并提供更持久的免疫力。然而，泰国尚未对 NGIV 进行经济评估。
我们使用结合了流行病学和经济学的模型，估算了 2005 年至 2009 年期间泰国 NGIV 的健康影响和成本效益。我们根据世界卫生组织（WHO）对 NGIV 产品特性的偏好，根据实验室确诊的流感病例数据对模型进行拟合，然后根据不同的疫苗接种情况模拟流感感染、症状病例、住院和死亡人数。我们使用之前对流感健康结果的成本和残疾调整生命年（DALY）的估计值来估算增量净货币收益、疫苗临界价格和预算影响。
在当前疫苗接种计划下，估计有 6100 万流感感染。使用改进疫苗将覆盖率提高到 50%可将感染人数减少到 2300 万至 5700 万之间，如果使用通用疫苗，感染人数则减少到 2100 万至 4900 万之间，这取决于目标年龄组。根据比较对象的不同，最小改进疫苗的 NGIV 单价范围为每剂 2.80 美元至 12.90 美元，而通用疫苗的单价范围为每剂 24.60 美元至 69.90 美元。
在泰国，使用 NGIV 的流感免疫计划预计将带来巨大的健康收益，并且具有成本效益。然而，即使从长远来看 NGIV 甚至可能具有成本节约效果，但即使可以以最大临界价格的大幅折扣来采购疫苗，泰国政府也可能面临重大预算影响。
