摘要
目的建立戊肝多途径传播的动力学模型,并将其应用于长沙市戊肝疫情,评估干预措施的效果。方法建立有、无干预措施的易感者-潜伏期者-染病者/隐性感染者-移出者-传播介质模型,利用长沙市戊肝发病数据、人口学数据、干预措施的特点和模型假设,估计模型的各参数,设定初始值,使用Matlab7.1进行模型仿真。结果当有效再生数λc(2008年以前)=0.226、λc(2008年以后)=0.201时,模型模拟的疫情与实际疫情最为接近。无干预情况下,2011年开始疫情发展速度加快,2020年将达到疫情的高峰,之后便开始下降。模拟结果显示:若从2010年12月开始采取干预措施,单纯去除外界传播介质,疫情持续约2个月后开始迅速下降,至2012年疫情结束;若同时去除外界传播介质和隔离患者,则2011年疫情便已结束。若每月仅对1‰的易感者接种疫苗,疫情有所控制,但仍存在;当每月接种比例为2‰时,戊肝疫情被有效控制;当每月接种比例为3‰时,疫情控制效果与当每月接种比例为2‰时基本相当。结论 SEIARW模型能较好地模拟长沙市戊肝疫情。单纯去除外界传播介质能较好地控制长沙市戊肝疫情,去除外界传播介质同时隔离患者的联合干预措施控制疫情的效果更好。当每月疫苗接种达到2‰时,仅靠疫苗接种就能很好控制戊肝疫情。
Objective To develop a multiple transmission pathways dynamic model of Hepatitis E and to apply it to assess the effects of interventions in Changsha. Methods We developed a susceptible-exposed-infectious/asymptomatic-removed-water/food （ SE- IARW） model and expanded the SEIARW model by including intervention measures. Based on the data of Hepatitis E epidemic and de- mography of Changsha, available intervention measures and model assumptions, we estimated parameters of model and determined the ini- tial values, and then simulated the effects of intervention measures using Matlab7.1 software. Results We determined the values of basic reproduction number pre-2008 （Ac = 0. 226） and since-2008 （Ac = 0. 201 ） because the simulated data were most close to actual data when A c = 0. 226 and 0. 201. When no interventions were taken, since 2011, the epidemic of Hepatitis E began to develop quickly and would reach the peak in 2020 ; after then, the epidemic would fade down. Simulated results showed： if the propagation medium of outside environ- ment was removed from December,2010 ,the epidemic would last for 2 months ,and end in 2012 ; if both the removal of propagation medi- um and case quarantine were implemented, the epidemic of Hepatitis E would end in 2011 ; if merely 1%o of susceptible persons were vac- cinated monthly,the epidemic would be prevented partly. When 2%o of susceptible persons were vaccinated every month, the epidemic would be prevented effectively. Compared with 2%o of susceptible persons were vaccinated every month, the prevention effect was almost the same when 3%o of susceptible persons were vaccinated every month. Conclusion SEIARW model is good in modeling the epidemic of Hepatitis E in Changsha. The removal of propagation medium can effectively curb the epidemic of Hepatitis E in Changsha. The effect would be better when the removal of propagation medium and case isolation are taken together. The epidemic of Hepatitis E could be pre- vented effectively when ≥2% of susceptible persons are vaccinated every month.
出处
《中国卫生统计》
CSCD
北大核心
2014年第2期257-262,共6页
Chinese Journal of Health Statistics
基金
湖南省卫生厅科研项目(B2012-138)
2009教育部新世纪人才计划项目(NCET-10-0782)资助
关键词
动力学模型
戊肝
多途径传播
隔离
疫苗
Dynamic model
Hepatitis E
Multiple transmission pathways
Isolation
Vaccine
