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Duelling timescales of host mixing and disease spread determine invasion of disease in structured populations

P.C. Cross·James O. Lloyd-Smith·P.L.F. Johnson·W.M. Getz
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Abstract

The epidemic potential of a disease is traditionally assessed using the basic reproductive number, R 0 . However, in populations with social or spatial structure a chronic disease is more likely to invade than an acute disease with the same R 0 , because it persists longer within each group and allows for more host movement between groups. Acute diseases ‘perceive’ a more structured host population, and it is more important to consider host population structure in analyses of these diseases. The probability of a pandemic does not arise independently from characteristics of either the host or disease, but rather from the interaction of host movement and disease recovery timescales. The R * statistic, a group-level equivalent of R 0 , is a better indicator of disease invasion in structured populations than the individual-level R 0 .

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P.C. Cross, James O. Lloyd-Smith, P.L.F. Johnson, W.M. Getz. 2005. Duelling timescales of host mixing and disease spread determine invasion of disease in structured populations. https://doi.org/10.1111/j.1461-0248.2005.00760.x

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