Wong Carlos, Jiang Minghuan, You Joyce H S
School of Pharmacy, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, N.T, Hong Kong.
PLoS One. 2016 Dec 22;11(12):e0169030. doi: 10.1371/journal.pone.0169030. eCollection 2016.
The influenza vaccine coverage rate of children is low in Hong Kong. Microneedle patches (MNPs) is a technology under development for painless delivery of vaccines. This study aimed to examine the potential clinical outcomes and direct medical costs of an influenza program offering MNP vaccine to children who have declined intramuscular (IM) vaccine in Hong Kong.
A decision model was designed to compare potential outcomes between IM vaccine program and a program offering MNP vaccine to those declined IM vaccine (IM/MNP program) in a hypothetical cohort of children over one-year time horizon. The model outcomes included direct medical cost, influenza infection rate, mortality rate, and quality-adjusted life-years (QALYs) loss. Model inputs were retrieved from published literature. Sensitivity analyses were performed to examine the robustness of model results.
In base-case analysis, IM/MNP program was more costly per child (USD19.13 versus USD13.69; USD1 = HKD7.8) with lower influenza infection rate (98.9 versus 124.8 per 1,000 children), hospitalization rate (0.83 versus 1.05 per 1,000 children) and influenza-related mortality rate (0.00042 versus 0.00052 per 1,000 children) when compared to IM program. The incremental cost per QALY saved (ICER) of IM/MNP program versus IM program was 27,200 USD/QALY. Using gross domestic product (GDP) per capita of Hong Kong (USD40,594) as threshold of willingness-to-pay (WTP) per QALY, one-way sensitivity analysis found ICER of IM/MNP to exceed WTP when duration of illness in outpatient setting was <5.7 days or cost per MNP vaccine was >1.39-time of IM vaccine cost. In 10,000 Monte Carlo simulations, IM/MNP program was the preferred option in 57.28% and 91.68% of the time, using 1x and 3x GDP per capita as WTP threshold, respectively.
Acceptance of IM/MNP program as the preferred program was subject to the WTP threshold, duration of illness in outpatient settings, and cost of MNP vaccine.
香港儿童流感疫苗接种率较低。微针贴片（MNPs）是一种正在研发的用于无痛接种疫苗的技术。本研究旨在探讨在香港为拒绝接种肌肉注射（IM）疫苗的儿童提供MNPs流感疫苗接种计划的潜在临床结局和直接医疗成本。
设计了一个决策模型，在一个假设的儿童队列中，比较IM疫苗接种计划与为拒绝IM疫苗的儿童提供MNPs疫苗接种计划（IM/MNP计划）在一年时间范围内的潜在结局。模型结局包括直接医疗成本、流感感染率、死亡率和质量调整生命年（QALYs）损失。模型输入数据来自已发表的文献。进行敏感性分析以检验模型结果的稳健性。
在基础病例分析中，与IM计划相比，IM/MNP计划每个儿童的成本更高（19.13美元对13.69美元；1美元=7.8港元），流感感染率更低（每1000名儿童中98.9例对124.8例）、住院率更低（每1000名儿童中0.83例对1.05例）以及流感相关死亡率更低（每1000名儿童中0.00042例对0.00052例）。IM/MNP计划相对于IM计划每挽救一个QALY的增量成本（ICER）为27,200美元/QALY。以香港人均国内生产总值（GDP）（40,594美元）作为每个QALY的支付意愿（WTP）阈值，单向敏感性分析发现，当门诊患病时长<5.7天或每剂MNPs疫苗成本>IM疫苗成本的1.39倍时，IM/MNP计划的ICER超过WTP。在10,000次蒙特卡洛模拟中，分别以1倍和3倍人均GDP作为WTP阈值时，IM/MNP计划在57.28%和91.68%的情况下是首选方案。
IM/MNP计划是否被接受为首选方案取决于WTP阈值、门诊患病时长以及MNPs疫苗成本。
