Tracking the dynamics of pathogen interactions: modeling ecological and immune-mediated processes in a two-pathogen single-host system.
Traditionally, epidemiological studies have focused on understanding the dynamics of a single pathogen, assuming no interactions with other pathogens. Recently, a large body of work has begun to explore the effects of immune-mediated interactions, arising from cross-immunity and antibody-dependent enhancement, between related pathogen strains. In addition, ecological processes such as a temporary period of convalescence and pathogen-induced mortality have led to the concept of ecological interference between unrelated diseases. There remains, however, the need for a systematic study of both immunological and ecological processes within a single framework. In this paper, we develop a general two-pathogen single-host model of pathogen interactions that simultaneously incorporates these mechanisms. We are then able to mechanistically explore how immunoecological processes mediate interactions between diseases for a pool of susceptible individuals. We show that the precise nature of the interaction can induce either competitive or cooperative associations between pathogens. Understanding the dynamic implications of multi-pathogen associations has potentially important public health consequences. Such a framework may be especially helpful in disentangling the effects of partially cross-immunizing infections that affect populations with a pre-disposition towards immunosuppression such as children and the elderly.
Vasco
Daniel A
DA
Institute of Ecology, University of Georgia, Athens, GA 30602, USA. vasco@uga.edu
Wearing
Helen J
HJ
Rohani
Pejman
P
D000368:Aged; D002648:Child; D003141:Communicable Diseases / Q000276:immunology* / Q000382:microbiology / Q000635:transmission; D004196:Disease Outbreaks; D004198:Disease Susceptibility / Q000276:immunology / Q000382:microbiology; D018562:Disease Transmission, Infectious; D006801:Humans; D007108:Immune Tolerance / Q000276:immunology; D008433:Mathematics; D008954:Models, Biological; D011790:Quarantine