Confidence in parameter estimation from epidemic data

Emergence of elevated levels of multiple infection in spatial host-virus dynamicsBradford Taylor1, Catherine Penington2, Joshua Weitz3,1 1School of Physics and 3School of Biology, Georgia Institute of Technology2School of Mathematical Sciences, Queensland University of Technologyhttp://ecotheory.biology.gatech.eduQuantitative Laws II

Multiple infection allows intracellular interactions between viruses

La Scola et al, Nature (2008)Coinfection alters ecological parameters

2

Multiple infections alter evolutionary rates due to shared resources

Recombination vs. Complementation

Multiple infection rates are unknown in vivo

4

How does space affect:the distribution of multiplicity of infection (MOI)?

RM Donlan,Emerg infect dis, 2002

Adsorption mediates clusteringLow adsorptionHigh adsorption

Well-mixed model dynamics

HostInfectedhostsViruses

Well-mixed model yields geometric MOI distribution

HostInfectedhostsViruses

Geometric distribution for MOI

MOI distribution follows geometric distribution for low adsorption

Clustered MOI distributions feature fat tails

How many viruses are colocated with a host of a specific MOI?MOI Layer (internal viruses)Viral Layer (external viruses)11

How many viruses are colocated with a host of a specific MOI?MOI Layer (internal viruses)Viral Layer (external viruses)

12

How many viruses are colocated with a host of a specific MOI?MOI Layer (internal viruses)Viral Layer (external viruses)

113

How many viruses are colocated with a host of a specific MOI?MOI Layer (internal viruses)Viral Layer (external viruses)

1214

Random dispersal gives Poisson distribution of viruses

15No clusteringclustering

Clustered Viral distribution skew right with increasing MOI16No clusteringclustering

Clustered Viral distribution skew right with increasing MOI17No clusteringclustering

Clustered Viral distribution skew right with increasing MOI18No clusteringclustering

Clustered Viral distribution skew right with increasing MOI19No clusteringclustering

Clustered Viral distribution skew right with increasing MOI20No clusteringclustering

Well-mixed model yields geometric MOI distribution

HostInfectedhostsViruses

Deviates from geometric distribution

Clustered MOI distributions feature fat tails

Multiple infection dynamics driven by invasions of clusters

Invasions of larger clusters skews viral distributions

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Invasions of larger clusters skews viral distributions

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ConclusionsHigh adsorption leads to clusteringClustering leads to fat tails in MOI distributionCluster invasions drive the dynamics to skew MOI distributions

Future work: spatial models of Virophageviruses of virusesTaylor et al,JTB (2014)

Paired Entry Mode (PEM)

Independent Entry Mode (IEM)

Desnues et al. PNAS (2012)Fischer and Suttle Science (2011)

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AcknowledgementsWeitz Lab (GaTech)Funding: Quantitative Laws IINSF Physics of Living SystemsJames S Mcdonnell FoundationNerem FellowshipBurroughs Wellcome Fund

AcknowledgementsQuestions?

BP Taylor, CJ Penington, JS WeitzbioRxiv: 048876Weitz Lab (GaTech)Funding: Quantitative Laws IINSF Physics of Living SystemsJames S Mcdonnell FoundationNerem FellowshipBurroughs Wellcome Fund

Analogous PDE model31

Parametrize based on prochlorococcussingletime stepSystem size: 500 x 500 lattice pts= ml

32Backup slideList processes