Dorratoltaj Nargesalsadat, Marathe Achla, Lewis Bryan L, Swarup Samarth, Eubank Stephen G, Abbas Kaja M
Department of Population Health Sciences, Virginia Tech, Blacksburg, VA, United States of America.
Network Dynamics and Simulation Science Lab, Biocomplexity Institute, Virginia Tech, Blacksburg, VA, United States of America.
PLoS Comput Biol. 2017 Jun 1;13(6):e1005521. doi: 10.1371/journal.pcbi.1005521. eCollection 2017 Jun.
The study objective is to estimate the epidemiological and economic impact of vaccine interventions during influenza pandemics in Chicago, and assist in vaccine intervention priorities. Scenarios of delay in vaccine introduction with limited vaccine efficacy and limited supplies are not unlikely in future influenza pandemics, as in the 2009 H1N1 influenza pandemic. We simulated influenza pandemics in Chicago using agent-based transmission dynamic modeling. Population was distributed among high-risk and non-high risk among 0-19, 20-64 and 65+ years subpopulations. Different attack rate scenarios for catastrophic (30.15%), strong (21.96%), and moderate (11.73%) influenza pandemics were compared against vaccine intervention scenarios, at 40% coverage, 40% efficacy, and unit cost of $28.62. Sensitivity analysis for vaccine compliance, vaccine efficacy and vaccine start date was also conducted. Vaccine prioritization criteria include risk of death, total deaths, net benefits, and return on investment. The risk of death is the highest among the high-risk 65+ years subpopulation in the catastrophic influenza pandemic, and highest among the high-risk 0-19 years subpopulation in the strong and moderate influenza pandemics. The proportion of total deaths and net benefits are the highest among the high-risk 20-64 years subpopulation in the catastrophic, strong and moderate influenza pandemics. The return on investment is the highest in the high-risk 0-19 years subpopulation in the catastrophic, strong and moderate influenza pandemics. Based on risk of death and return on investment, high-risk groups of the three age group subpopulations can be prioritized for vaccination, and the vaccine interventions are cost saving for all age and risk groups. The attack rates among the children are higher than among the adults and seniors in the catastrophic, strong, and moderate influenza pandemic scenarios, due to their larger social contact network and homophilous interactions in school. Based on return on investment and higher attack rates among children, we recommend prioritizing children (0-19 years) and seniors (65+ years) after high-risk groups for influenza vaccination during times of limited vaccine supplies. Based on risk of death, we recommend prioritizing seniors (65+ years) after high-risk groups for influenza vaccination during times of limited vaccine supplies.
该研究的目的是评估流感大流行期间疫苗干预措施对芝加哥的流行病学和经济影响，并协助确定疫苗干预的优先次序。在未来的流感大流行中，如2009年甲型H1N1流感大流行那样，疫苗引入延迟、疫苗效力有限且供应受限的情况并非不可能出现。我们使用基于主体的传播动力学模型对芝加哥的流感大流行进行了模拟。将人群按0至19岁、20至64岁和65岁及以上亚人群分为高风险和非高风险组。针对灾难性（30.15%）、强（21.96%）和中度（11.73%）流感大流行的不同发病率情景，与疫苗干预情景进行了比较，疫苗覆盖率为40%，效力为40%，单位成本为28.62美元。还对疫苗依从性、疫苗效力和疫苗开始日期进行了敏感性分析。疫苗优先排序标准包括死亡风险、总死亡人数、净效益和投资回报率。在灾难性流感大流行中，65岁及以上高风险亚人群的死亡风险最高；在强和中度流感大流行中，0至19岁高风险亚人群的死亡风险最高。在灾难性、强和中度流感大流行中，20至64岁高风险亚人群的总死亡人数和净效益比例最高。在灾难性、强和中度流感大流行中，0至19岁高风险亚人群的投资回报率最高。基于死亡风险和投资回报率，可将三个年龄组亚人群中的高风险组列为优先接种对象，并且疫苗干预措施对所有年龄和风险组都具有成本节约效益。在灾难性、强和中度流感大流行情景中，由于儿童的社交网络更大且在学校中有同类相聚互动，其发病率高于成年人和老年人。基于投资回报率以及儿童中较高的发病率，我们建议在疫苗供应有限时，在高风险组之后将儿童（0至19岁）和老年人（65岁及以上）列为流感疫苗接种的优先对象。基于死亡风险，我们建议在疫苗供应有限时，在高风险组之后将老年人（65岁及以上）列为流感疫苗接种的优先对象。
