中华预防医学杂志
中華預防醫學雜誌
중화예방의학잡지
CHINESE JOURNAL OF
2012年
4期
343-347
,共5页
传染病控制%疾病暴发流行%时滞离散SEIR模型
傳染病控製%疾病暴髮流行%時滯離散SEIR模型
전염병공제%질병폭발류행%시체리산SEIR모형
Communicable disease control%Disease outbreaks%SEIR model with a discrete time delay
目的 应用时滞离散SEIR模型对一起水痘暴发疫情开展预测及控制措施效果理论评价.方法 在对连续SEIR模型作离散化处理的基础上,考虑水痘潜隐期和传染期的时滞效应建立时滞离散模型,以拟合模型得到的理论发病数进行疫情预测.比较实施不同控制措施时的模拟结果,对控制措施效果进行理论评价.结果 不采取控制措施时,模型估计的理论罹患率为30.16％(504/1671),流行过程历时4个月,发病高峰出现在首例发病后的78 d,流行过程可见明显的“代际”现象,每代之间间隔约2周.实际发病数与未采取控制措施的模拟发病数相比减少了 89.48％(451/504).模拟对所有病例在其发病当日进行隔离,在首发病例发病的当天及第14、28、42天开始实施隔离措施,得到的总发病数分别为22、59、127和220例.模拟在首发病例发病的第14天开始实施隔离措施,当隔离率为30％、50％、70％、90％时,得到的总发病数分别为485、457、386和169例.模拟应急接种的接种率为100％,在首发病例发病的当天及第14、28、42天实施接种,得到的总发病数分别为7、26、81和202例.模拟在首发病例发病的第14天实施应急接种,当接种率为30％、50％、70％、90％时,得到的总发病数分别为354、246、127和40例.结论 模型预测的理论发病数可以为水痘暴发时现场控制措施效果评价提供参照.模拟结果表明,越早实施病例隔离和应急接种措施收益越明显,应急接种的效果优于同等条件下实施病例隔离的效果.
目的 應用時滯離散SEIR模型對一起水痘暴髮疫情開展預測及控製措施效果理論評價.方法 在對連續SEIR模型作離散化處理的基礎上,攷慮水痘潛隱期和傳染期的時滯效應建立時滯離散模型,以擬閤模型得到的理論髮病數進行疫情預測.比較實施不同控製措施時的模擬結果,對控製措施效果進行理論評價.結果 不採取控製措施時,模型估計的理論罹患率為30.16％(504/1671),流行過程歷時4箇月,髮病高峰齣現在首例髮病後的78 d,流行過程可見明顯的“代際”現象,每代之間間隔約2週.實際髮病數與未採取控製措施的模擬髮病數相比減少瞭 89.48％(451/504).模擬對所有病例在其髮病噹日進行隔離,在首髮病例髮病的噹天及第14、28、42天開始實施隔離措施,得到的總髮病數分彆為22、59、127和220例.模擬在首髮病例髮病的第14天開始實施隔離措施,噹隔離率為30％、50％、70％、90％時,得到的總髮病數分彆為485、457、386和169例.模擬應急接種的接種率為100％,在首髮病例髮病的噹天及第14、28、42天實施接種,得到的總髮病數分彆為7、26、81和202例.模擬在首髮病例髮病的第14天實施應急接種,噹接種率為30％、50％、70％、90％時,得到的總髮病數分彆為354、246、127和40例.結論 模型預測的理論髮病數可以為水痘暴髮時現場控製措施效果評價提供參照.模擬結果錶明,越早實施病例隔離和應急接種措施收益越明顯,應急接種的效果優于同等條件下實施病例隔離的效果.
목적 응용시체리산SEIR모형대일기수두폭발역정개전예측급공제조시효과이론평개.방법 재대련속SEIR모형작리산화처리적기출상,고필수두잠은기화전염기적시체효응건립시체리산모형,이의합모형득도적이론발병수진행역정예측.비교실시불동공제조시시적모의결과,대공제조시효과진행이론평개.결과 불채취공제조시시,모형고계적이론리환솔위30.16％(504/1671),류행과정력시4개월,발병고봉출현재수례발병후적78 d,류행과정가견명현적“대제”현상,매대지간간격약2주.실제발병수여미채취공제조시적모의발병수상비감소료 89.48％(451/504).모의대소유병례재기발병당일진행격리,재수발병례발병적당천급제14、28、42천개시실시격리조시,득도적총발병수분별위22、59、127화220례.모의재수발병례발병적제14천개시실시격리조시,당격리솔위30％、50％、70％、90％시,득도적총발병수분별위485、457、386화169례.모의응급접충적접충솔위100％,재수발병례발병적당천급제14、28、42천실시접충,득도적총발병수분별위7、26、81화202례.모의재수발병례발병적제14천실시응급접충,당접충솔위30％、50％、70％、90％시,득도적총발병수분별위354、246、127화40례.결론 모형예측적이론발병수가이위수두폭발시현장공제조시효과평개제공삼조.모의결과표명,월조실시병례격리화응급접충조시수익월명현,응급접충적효과우우동등조건하실시병례격리적효과.
Objective To forecast the epidemic trend and to evaluate the effect of outbreak control measures by investigation of a varicella outbreak event with a discrete time delay SEIR model.Methods A discrete time delay model was formulated by discretization method based on a continuous SEIR model with the consideration of the time delay effect on latent period and communicable period.The epidemic trend forecast was carried out based on the number of expected cases.The theoretical effect evaluation was assessed by comparing the results from different emergency control measures.Results Without any control measures,the theoretical attack rate was 30.16％ (504/1671 ).The course of the epidemic lasted for 4 months and the peak epidemic time was 78 days after the onset of the first case.Generation phenomenon had been observed in the course of the epidemic with the interval of two weeks.The actual number of cases was decreased by 89.48％ (451/504) compared with the number of expected cases under no control measure scenario.With the rigorous quarantine measure for all cases on their onset day,when the measure was conducted on 0,14,28,42 days after the onset of the first case,the total numbers of expected cases were 22,59,127 and 220respectively.With the quarantine measure conducted on 14 days after the onset of the first case,when the proportion of quarantine was 30％,50％,70％,90％,the total numbers of expected cases were 485,457,386 and 169,respectively.With the emergent vaccination for all persons,when the measure was conducted on 0,14,28,42 days after the onset of the first case,the total numbers of expected cases were 7,26,81and 202 respectively.With the emergent vaccination conducted on 14 days after the onset of the first case,when the immunization coverage rate was 30％,50％,70％,90％,the total numbers of expected cases were 354,246,127 and 40,respectively.Conclusion The number of expected cases can be regarded as the reference to evaluate the effect of control measures.The simulation results suggest that it will get more benefits to conduct control neasures earlier in varicella outbreak events,and the effect of emergent vaccination is better than that of quarantine measure under the same conditions.
