Back in 2004, a team at the Harvard School of Public Health had modelled the transmissibility patterns of the 1918 virus, more precisely they calculated its reproductive number, 'R', in relation to its serial interval, 'v'.

早在2004年，哈佛大学公共卫生学院的一个团队就建立了1918年病毒传播模式的模型，他们更精确地计算了病毒的繁殖数量R与序列间隔v之间的关系。