Agent-Based Modelling Laboratory, York University, Toronto, Ontario M3J 1P3, Canada.
Immunization & Policy Translation, 16 Fire Route 105, Trent Lakes, Ontario K0M 1A0, Canada.
Vaccine. 2018 Mar 14;36(12):1681-1688. doi: 10.1016/j.vaccine.2018.01.047. Epub 2018 Feb 16.
The preceding decade has witnessed the emergence of severe community-acquired acute infections caused by Haemophilus influenzae serotype a (Hia), with alarming incidence rates in North America, particularly among indigenous populations. The remarkable success of Hib conjugate vaccine over the past 20 years signify the development of an Hia vaccine candidate as a prevention measure to reduce the incidence of invasive Hia disease. However, quantifications of the long-term epidemiologic and economic impacts of vaccination are needed to inform decision on investment in Hia vaccine development and immunization programs. We sought to evaluate the cost-effectiveness of an Hia vaccine with a similar routine infant immunization schedules currently in practice for Hib in Canada. We developed and parameterized an agent-based simulation model using age-specific incidence rates reported for Nunavut, a Canadian territory with predominantly aboriginal populations. Our results, based on statistical analyses of the incremental cost-effectiveness ratio, show that an Hia conjugate vaccine is highly cost-effective. Sustaining an immunization program with vaccine coverages of 77% for primary series and 93% for booster dose over a 10-year period reduces the incidence of invasive disease by 63.8% on average from 9.97 to 3.61 cases, per 100,000 population. The overall costs of disease management in year 10 are reduced by 53.4% from CDN $1.863 million (95% CI: $1.229-$2.519 M) to CDN $0.868 million (95% CI: $0.627-$1.120 M). The findings suggest an important role for a conjugate vaccine in managing Hia disease as a growing public health threat.
在过去的十年中，甲型流感嗜血杆菌（Hia）引起的严重社区获得性急性感染已经出现，在北美，尤其是在土著人群中，发病率令人震惊。过去 20 年来，Hib 结合疫苗的显著成功表明，开发 Hia 疫苗候选物作为预防措施来降低侵袭性 Hia 疾病的发病率是可行的。然而，需要对疫苗接种的长期流行病学和经济影响进行量化，以便为 Hia 疫苗开发和免疫规划的投资决策提供信息。我们旨在评估与目前在加拿大 Hib 常规婴儿免疫接种计划中使用的类似免疫计划的 Hia 疫苗的成本效益。我们使用特定年龄组报告的发病率数据，为加拿大努纳武特地区（一个以土著居民为主的地区）开发并参数化了基于代理的模拟模型。我们的结果基于对增量成本效益比的统计分析，表明 Hia 结合疫苗具有很高的成本效益。在 10 年内维持疫苗覆盖率为初级系列 77%和加强剂量 93%的免疫计划，可使侵袭性疾病的发病率平均降低 63.8%，从每 10 万人中 9.97 例降至 3.61 例。第 10 年疾病管理的总费用从 186.3 万加元（95%CI：122.9-251.9 万加元）降至 86.8 万加元（95%CI：62.7-112.0 万加元），降低了 53.4%。研究结果表明，作为日益严重的公共卫生威胁，结合疫苗在管理 Hia 疾病方面发挥着重要作用。
