Data from: Seasonal variation in daily patterns of social contacts in the European badger Meles meles

Social interactions among hosts influence the persistence and spread of infectious pathogens. Daily and seasonal variation in the frequency and type of social interactions will play an important role in disease epidemiology and, alongside other factors, may have an influence on wider disease dynamics by causing seasonal forcing of infection, especially if the seasonal variation experienced by a population is considerable. We explored temporal variation in within-group contacts in a high-density population of European badgers Meles meles naturally infected with Mycobacterium bovis (the causative agent of bovine tuberculosis). Summer contacts were more likely and of longer duration during the daytime, while the frequency and duration of winter contacts did not differ between day and night. In spring and autumn, within-group contacts peaked at dawn and dusk, corresponding with when they were of shortest duration with reduced potential for aerosol transmission of pathogens. Summer and winter could be critical for transmission of M. bovis in badgers, due to the high frequency and duration of contacts during resting periods, and we discuss the links between this result and empirical disease data. This study reveals clear seasonality in daily patterns of contact frequency and duration in species living in stable social groups, suggesting that changes in social contacts could drive seasonal forcing of infection in wildlife populations even when the number of individuals interacting remains similar.

宿主间的社会互动可影响传染性病原体的存续与传播。社会互动的频率与类型兼具日节律与季节变化，这在疾病流行病学领域具有重要意义；与其他因素一道，这类变化可通过引发感染的季节强制作用（seasonal forcing）影响更广泛的疾病传播动态，尤其当种群所经历的季节波动幅度较大时。
本研究针对自然感染牛分枝杆菌（Mycobacterium bovis，牛结核病的致病菌）的高密度欧洲獾（Meles meles）种群，探究了种群内接触行为的时间变化规律。夏季的接触行为更为频繁且持续时间更长，且多集中于日间；而冬季的接触行为频率与时长在昼夜间无显著差异。春秋两季的种群内接触行为在黎明与黄昏达到峰值，此时接触持续时间最短，病原体的气溶胶传播潜力也随之降低。
由于休憩时段的接触行为频率高、持续时间久，夏季与冬季或为獾群中牛分枝杆菌传播的关键时期；本研究还讨论了该结果与实际疾病观测数据之间的关联。
本研究揭示了稳定社会群动物的接触频率与时长的日节律存在显著季节特征，这表明即便参与互动的个体数量保持恒定，社会接触的变化仍可驱动野生动物种群的感染季节强制作用。