Interplay between competitive and cooperative interactions in a three-player pathogen system
Interplay between competitive and cooperative interactions in a three-player pathogen system
复制标题
DOI：
10.1098/rsos.190305
复制
发表时间：
2020-01-22
影响因子：
3.5
通讯作者：
Poletto，Chiara
中科院分区：
文献类型：
--
作者：
Pinotti，Francesco;Ghanbarnejad，Fakhteh;Poletto，Chiara
在生态系统中，病原体之间的异质相互作用同时发生。例如，当两种病原体合作时，就会发生这种情况，而同时，这些病原体的多个菌株共同循环和竞争。值得注意的例子包括人类免疫缺陷病毒与结核病的耐药和敏感菌株的合作，或一些呼吸道感染与肺炎链球菌菌株的合作。分别关注竞争或合作的模型未能描述这些并发的相互作用如何影响此类疾病的流行病学。我们研究了这个问题，考虑两个合作的病原体，其中一个病原体进一步结构化的两个菌株。传播遵循一个易感染-感染-易感的过程，菌株在传播性和与其他病原体合作的程度上不同。我们结合了平均场的稳定性分析与随机模拟网络考虑良好的混合和结构化的人口。我们观察到一个复杂的相图的出现，其中的条件，较少的传输，但更多的合作应变占主导地位是不平凡的，例如非单调边界和双稳态。与群落结构相结合，合作病原体的存在通过打破空间对称性和动态地创建不同的生态位使菌株之间能够共存。这些结果揭示了可能影响公共卫生关注的疾病流行病学的生态机制。
In ecological systems, heterogeneous interactions between pathogens take place simultaneously. This occurs, for instance, when two pathogens cooperate, while at the same time, multiple strains of these pathogens co-circulate and compete. Notable examples include the cooperation of human immunodeficiency virus with antibiotic-resistant and susceptible strains of tuberculosis or some respiratory infections withStreptococcus pneumoniaestrains. Models focusing on competition or cooperation separately fail to describe how these concurrent interactions shape the epidemiology of such diseases. We studied this problem considering two cooperating pathogens, where one pathogen is further structured in two strains. The spreading follows a susceptible-infected-susceptible process and the strains differ in transmissibility and extent of cooperation with the other pathogen. We combined a mean-field stability analysis with stochastic simulations on networks considering both well-mixed and structured populations. We observed the emergence of a complex phase diagram, where the conditions for the less transmissible, but more cooperative strain to dominate are non-trivial, e.g. non-monotonic boundaries and bistability. Coupled with community structure, the presence of the cooperative pathogen enables the coexistence between strains by breaking the spatial symmetry and dynamically creating different ecological niches. These results shed light on ecological mechanisms that may impact the epidemiology of diseases of public health concern.