Experimental infectious pancreatic necrosis infections: propagative or point-source epidemic?

G. Smith; J. Bebak; P. E. McAllister

doi:10.1016/s0167-5877(00)00176-8

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Experimental infectious pancreatic necrosis infections: propagative or point-source epidemic?

G. Smith·J. Bebak·P. E. McAllister

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Abstract

Experimentally initiated epidemics of infectious pancreatic necrosis in rainbow-trout fry were analyzed using a modification of the standard mathematical model for a simple propagative epidemic. Contrary to expectations, the value of the transmission parameter ( β ) was inversely related to initial density of susceptible hosts. This anomaly can be explained if we assume that the experimental epidemics were point-source rather than propagative epidemics. The implications of this conclusion for modeling experimental and natural epidemics are discussed.

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G. Smith, J. Bebak, P. E. McAllister. 2000. Experimental infectious pancreatic necrosis infections: propagative or point-source epidemic?. https://doi.org/10.1016/s0167-5877(00)00176-8

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