Data and Code supporting manuscript from Quantifying the consequences of measles-induced immune modulation for whooping cough epidemiology

Measles, an acute viral disease, continues to be an important cause of childhood mortality worldwide. Infection with the measles virus is thought to be associated with a transient but profound period of immune suppression. Recently, it has been claimed that measles-induced immune manipulation lasts for about 30 months and results in increased susceptibility to other co-circulating infectious diseases and more severe disease outcomes upon infection. We tested this hypothesis using model-based inference applied to parallel historical records of measles and whooping cough mortality and morbidity. Specifically, we used maximum likelihood to fit a mechanistic transmission model to incidence data from three different eras, spanning mortality records from 1904 to 1912 and 1922 to 1932 and morbidity records from 1946 to 1956. Our aim was to quantify the timing, severity and pathogenesis impacts of measles-induced immune modulation and their consequences for whooping cough epidemiology across a temporal gradient of measles transmission. We identified an increase in susceptibility to whooping cough following recent measles infection by approximately 85-, 10- and 36-fold for the three eras, respectively, although the duration of this effect was variable. Overall, while the immune impacts of measles may be strong and clearly evident at the individual level, their epidemiological signature in these data appears both modest and inconsistent.This article is part of the theme issue ‘Detection, forecasting and control of infectious disease epidemics: modelling outbreaks in humans, animals and plants Part 1’.

麻疹作为一种急性病毒性传染病，至今仍是全球范围内儿童死亡的重要病因之一。既往研究认为，麻疹病毒感染会引发一段短暂但显著的免疫抑制期。近期有研究提出，麻疹诱导的免疫调控异常可持续约30个月，会使宿主对其他同期流行的传染病易感性升高，且感染后病情更为严重。本研究采用基于模型的推断方法，结合麻疹与百日咳（whooping cough）的平行历史死亡与发病数据，对该假说进行了验证。具体而言，我们采用极大似然法（maximum likelihood），将机械传播模型（mechanistic transmission model）拟合至三个不同时期的发病数据：其中死亡数据覆盖1904年至1912年、1922年至1932年，发病数据则取自1946年至1956年。本研究旨在量化麻疹诱导的免疫调节效应的发生时序、严重程度及致病机制影响，并阐明其在麻疹传播的时间梯度下对百日咳流行病学特征的影响。我们发现，在三个研究时期中，近期麻疹感染后宿主对百日咳的易感性分别升高约85倍、10倍与36倍，不过该效应的持续时长存在差异。总体而言，尽管麻疹的免疫效应在个体层面可能较为显著且易于观测，但在本研究的数据中，其流行病学特征却表现得较为温和且缺乏一致性。本文属于专题刊《传染病流行的检测、预测与防控：人类、动物与植物暴发疫情建模（第一部分）》的组成部分。