Interplay between competitive and cooperative interactions in a three-player pathogen system

Abstract

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 HIV with antibiotic-resistant and susceptible strains of tuberculosis, or some respiratory infections with Streptococcus pneumoniae strains. 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 co-existence between strains by breaking the spatial symmetry 1 arXiv:1912.07289v1 [q-bio.PE]

Disentangling how multiple traits drive 2 strain frequencies in SIS dynamics with coinfection

“…Epidemiological models of coinfection have a long history of study (Levin and Pimentel, 1981;Adler and Brunet, 1991;Nowak and May, 1994;May and Nowak, 1995;van Baalen and Sabelis, 1995;Mosquera and Adler, 1998;Martcheva, 2009;Thieme, 2007;Alizon, 2013). Examples of multi-strain infectious agents where coinfection processes appear and shape epidemiology include Streptococcus pneumoniae bacteria (Lipsitch, 1997;Gjini et al, 2016), Bordetella pertussis (Nicoli et al, 2015), Mycobacterium tuberculosis (Cohen et al, 2012), Staphylococcus Aureus, (Pinotti et al, 2019) and many others, comprising plants (Susi et al, 2015;Halliday et al, 2020), and also inter-species co-colonization such as between Haemophilus Influenzae and pneumococcus serotypes (Margolis et al, 2010;Cobey and Lipsitch, 2013) and coinfection with different viruses (Furuya-Kanamori et al, 2016). Typically the strain-defining parameters vary much less within than between species.…”

Emergence of synergistic and competitive pathogens in a coevolutionary spreading model

“…Curiously, cases of cooperation have been reported also between distinct variants (quasispecies) of human H3N2 influenza [19,20]. Consequently, the amount of literature about the spreading of cooperative [21][22][23][24][25][26][27] and competitive [28][29][30][31][32][33] pathogens has grown over the years.…”

Is the ZIKV Congenital Syndrome and Microcephaly Due to Syndemism with Latent Virus Coinfection?

“…Certain cases are more susceptible to contracting one or more infectious diseases, which could completely recast the view of the ZIKV system in cases of interactions with other pathogens [ 85 ]. ZIKV can learn, be trained, and acquire numerous functions resulting from its contact with other viruses, which can be cooperative, competitive (e.g., interference), or synergistic interactions (e.g., accommodation) [ 49 , 86 ]. ZIKV and other viruses can encounter one another within an organism at different levels and at different periods of ZIKV illness (e.g., phases of incubation, symptomaticity (viremia), chronicity, and/or persistence) ( Figure 2 ), resulting in changes to the classical definition of ZIKV syndrome in terms of kinetics and disease progression, as well as to complications and also phenotype changes that mirror the tissue tropism effects related to ZIKV ( Figure 2 ) [ 87 , 88 , 89 ].…”