中国4种儿童易感传染病传播特性的分析

Analysis of the transmission characteristics of four childhood infectious diseases in China

目的 了解4种传染病发病数的周期性、传染率及其季节性的变化模式,为4种传染病的防控提供理论支持。方法 选取百日咳、猩红热、风疹、腮腺炎这4种有代表性的儿童易感传染病作为研究对象,分别建立时间序列易感者-感染者-恢复者(time series susceptible infected recovered, TSIR)模型,使用马尔科夫蒙特卡洛方法估计模型中的参数,分析这4种传染病传染率的季节性模式;根据不同传染病传染率的季节性模式,采取针对性控制措施,分析对未来发病数的影响效果。结果 4种传染病的传染率呈季节性变化,最低传染率均发生在7―8月,猩红热、风疹、腮腺炎的最高传染率发生在2―3月。传染率季节性受学生放假、春运影响。有无免疫实施不影响传染率的季节性模式。传染率季节性与病原体的异同存在关联性。结论 4种儿童易感传染病的传染率均具有季节性变化的特点,相应的季节性防控措施对减少发病数更为有效。

Objective This research aimed to understand the periodical pattern, transmission rate, and seasonality of four childhood infectious diseases, and to provide theoretical support for prevention and control. Methods We selected four typical childhood infectious diseases, including pertussis, scarlet fever, rubella, and mumps, as research objects. And established time series susceptible infected recovered(TSIR) model respectively for four diseases. The Markov chain Monte Carlo methods were used to estimate the parameters of TSIR models and analyze the seasonal patterns of the transmission rate. According to the seasonal pattern of different infectious diseases’ transmission rates, targeted prevention and control measures were adopted to analyze the effect on the number of future cases. Results The transmission rates of the four infectious diseases showed seasonal changes. The lowest transmission rates occured from July to August. The highest transmission rates of scarlet fever, rubella, and mump were from February to March. The transmission rate was affected seasonally by school holidays and the Spring Festival period. Having or not having immunization implementation did not affect the seasonal pattern of the transmission rate. The seasonality of transmission rate was related to the types of pathogens. Conclusions The transmission rates of the four childhood infectious diseases are characterized by seasonal changes. It is more effective to consider seasonality when implementing prevention and control measures to reduce the number of cases.