For emerging infectious disease with infectivity in incubation period, this paper studies the effect of quarantine measures for close contacts on the transmission of emerging infectious disease with the help of the differential equation model. The results show that as long as measures where close contacts are quarantined are taken, when to take measures is a very important factor. Under a given quarantine intensity, there is a phase transition structure about the start time of taking measures. Only when the start time of taking measure is earlier than the first critical moment of phase transition, the final cumulative number of patients and deaths can be stabilized in low level, so as to control the spread of epidemics. At the same time, whenever quarantine measures are taken, even if the quarantine intensity is not strong enough, the peak value of existing infectious individuals will decrease and the duration when the number of existing infectious individuals is high will be shortened, and the final cumulative number of patients and deaths will be significantly reduced.

对于潜伏期具有传染性的新兴传染病，本文借助微分方程模型研究了近距离接触检疫措施对新兴传染病传播的影响。结果表明，只要采取了隔离亲密接触的措施，何时采取措施是一个非常重要的因素。在给定的隔离强度下，关于采取措施的开始时间存在一个相变结构。只有在采取措施的开始时间早于相变的第一个关键时刻时，最终的患者累积总数和死亡人数才能稳定在较低水平，以控制流行病的蔓延。同时，无论何时采取隔离措施，即使隔离强度不够强，