Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ 08544, USA.
J R Soc Interface. 2011 Nov 7;8(64):1584-93. doi: 10.1098/rsif.2011.0062. Epub 2011 Apr 20.
Rotavirus is a major cause of mortality in developing countries, and yet the dynamics of rotavirus in such settings are poorly understood. Rotavirus is typically less seasonal in the tropics, although recent observational studies have challenged the universality of this pattern. While numerous studies have examined the association between environmental factors and rotavirus incidence, here we explore the role of intrinsic factors. By fitting a mathematical model of rotavirus transmission dynamics to published age distributions of cases from 15 countries, we obtain estimates of local transmission rates. Model-predicted patterns of seasonal incidence based solely on differences in birth rates and transmission rates are significantly correlated with those observed (Spearman's ρ = 0.65, p < 0.05). We then examine seasonal patterns of rotavirus predicted across a range of different birth rates and transmission rates and explore how vaccination may impact these patterns. Our results suggest that the relative lack of rotavirus seasonality observed in many tropical countries may be due to the high birth rates and transmission rates typical of developing countries rather than being driven primarily by environmental conditions. While vaccination is expected to decrease the overall burden of disease, it may increase the degree of seasonal variation in the incidence of rotavirus in some settings.
轮状病毒是发展中国家死亡的主要原因，但人们对这些地区轮状病毒的动态了解甚少。轮状病毒在热带地区的季节性通常较弱，尽管最近的观察性研究对这种模式的普遍性提出了挑战。虽然有许多研究探讨了环境因素与轮状病毒发病率之间的关系，但在这里，我们探讨了内在因素的作用。通过将轮状病毒传播动力学的数学模型拟合到来自 15 个国家的病例年龄分布，我们获得了当地传播率的估计值。仅基于出生率和传播率差异的模型预测的季节性发病率模式与观察到的模式显著相关（Spearman's ρ = 0.65，p < 0.05）。然后，我们检查了在一系列不同出生率和传播率下预测的轮状病毒的季节性模式，并探讨了疫苗接种可能如何影响这些模式。我们的研究结果表明，许多热带国家观察到的轮状病毒季节性相对较弱，可能是由于发展中国家典型的高出生率和传播率所致，而不是主要由环境条件驱动。虽然疫苗接种有望降低疾病的总体负担，但它可能会增加某些情况下轮状病毒发病率的季节性变化程度。
