Videos by CTW: From Within Host Dynamics to the Epidemiology of Infectious Disease
Parallels between metapopulations and disease dynamics
Within host dynamics in diseases is essentially the same as dynamics within metapopulations in an ecological context. I will review results from metapopulation models, and draw parallels to disease dynamics. I will emphasize both similarities and differences. The goal will be to see how various assumptions about within host (equivalently within patch) dynamics reduce th...
Systems biology of epidemiology From genes to environment
Traditional epidemiological models consists of compartmentalizing hosts into susceptible, exposed, infected, recovered (SEIR), and variations of this paradigm (e.g. SIR, SIR/SI, etc.). These models are challenged when the within-host dynamics of disease is taken into account with aspects such as: (i) Simultaneous Infection: Simultaneous presence of several distinc...
Some effects of host movement in vector-borne disease systems
Host movements can have a profound impact on the transmission of vector-borne diseases because they can increase or reduce he rate of contact between hosts and vectors. It is clear that host movement can introduce pathogens to new environments, but models suggest that it can also increase or decrease the basic reproduction number (R0) within an environment by influenci...
Ecological dynamics of a salmon parasite
In this talk I will outline the impact that parasitic sea lice have on the ecology of pacific salmon and the role that parasite spill over and spill back with aquaculture has taken in modifying the ecology of pacific salmon. These modifications are far reaching, and include changes in salmon returns, establishment of nonlinear population thresholds such as Allee e...
Flu in ducks and water - a multiscale modeling study
It has recently been suggested that for avian influenza viruses, prolonged persistence in the environment plays an important role in the transmission between birds. In such situations, influenza virus strains may face a trade-off: They need to persist well in the environment at low temperatures, but they also need to do well inside an infected bird at higher tempe...
Tracking dynamic innate immune responses in experimental malaria infection
Experimental malaria infections in non-human primates (NHPs) are a prime setting to assess the changing biological conditions associated with disease, notably with regards to the host immune system. While much attention has been focused on T-cell and B-cell dependent ("adaptive") responses that are key to vaccine development and long-term protection in m...
Spatial and Temporal Malaria Risk Profiles
The modern era of Amazon frontier expansion in Brazil witnessed the introduction of large-scale colonization projects focused on agriculture and wide-ranging human settlement, as well as the construction of infrastructure, such as roads and dams. These initiatives led to massive human migration, substantial environmental transformation, and severe malaria transmis...
Insights into Plasmodium vivax from spatial maps of human gene polymorphisms: Duffy blood group and G6PD deficiency.
Over a third of the world‚€™s population lives at risk of potentially life-threatening Plasmodium vivax malaria infections. Unique aspects of this parasite‚€™s biology and interactions with its human host make it harder to control and eliminate than the better studied Plasmodium falciparum...
Modeling The Blood Stage Infection In Malaria: Advantages Of Discrete Versus Continuous Approaches
The blood stage of a malaria infection is the final step of the dual-host multi-stage disease. It is at this stage that most symptoms manifest and where the outcome is critical for the future disease trajectory toward either chronic infection or death. The blood stage is marked by the interplay between malarial merozoites, the erythropoietic system, and the immune...
Systems-scale and integrative "omic" analysis of host-pathogen interactions in malaria
As part of the Malaria Host-Pathogen Interaction Center, our goal is to study and model the response of both host and pathogen to the course of malarial infection, treatment, and recurrence or recrudescence, using multiple levels of "omic" data. Detailed mathematical models are a desired ultimate product of our study of malaria, and while there are certa...
Epidemiology of tick-borne Rickettsia spp.
The incidence of tick-borne rickettsial disease in the southeastern United States has been rising steadily through the past decade, and the range expansions of tick species and tick-borne infectious agents, new and old, has resulted in an unprecedented mix of vectors and pathogens. The results of an ongoing 5-year surveillance project describe the relative abundan...
Within-host to population-level modeling of mycoplasmal conjunctivitis in wild birds
The pathogenic bacterium Mycoplasma gallisepticum jumped from poultry into North American House Finch populations during the early 1990s, and has since proven to be an accessible system in which to study the many faces of emerging infectious diseases in vertebrates. In this talk I'll begin by introducing the system, then I'll discuss...
Identifiability and interacting scales in modeling disease dynamics
Disease processes often involve interacting factors at multiple scales, which can affect both how we build models of these systems and the data sets needed to estimate model parameters. In this talk I will discuss some examples of disease transmission models that depend on processes at scales ranging from cellular to environmental, including cholera and human papi...
Disease invasion of community networks with environmental pathogen movement
Consider a set of communities (patches), connected to one another by a network. When can disease invade this network? Intuitively, this should depend upon both the properties of the communities, as well as on the network structure. Here we make this dependence explicit for a broad class of disease models with environmental pathogen movement. In particular, the roo...
Thresholds for Extinction in Stochastic Models of Infectious Diseases: Importance of Time and Location
Relations between Markov chain models and differential equation models for infectious diseases near the infection-free state are derived. Approximation of the Markov chain model by a multitype branching process leads to an estimate of the probability of disease extinction. We summarize some extinction results for multi-patch, multi-group, and multi-stage models of...
Optimal Control and Analysis of a Coupled ODE/PDE Immuno-epidemiological Model.
Optimal control can be used to design intervention strategies for the management of infectious diseases, and has been applied in immunological and epidemiological models separately. We formulate an immuno-epidemiological model of coupled within-host model of ODEs and between-host model of ODE and PDE. Existence and uniquen...
Deterministic within-host viral dynamics
In this talk, I will review the basic features of deterministic models of within-host viral dynamics. I will discuss the global asymptotic behavior of such models, and extensions of the stability results to models including multi-strain competition, antiviral treatment, and immune response.
Scientific Overview and Challenges
With this presentation I will try to set the stage for the modeling efforts to be discussed in the workshop. As the title ‚€œFrom Within Host Dynamics to the Epidemiology of Infectious Disease‚€? directly suggests, infectious diseases involve many scales, with respect to time, space, and organization, with the latter spanning the range ...