Chaos and complexity in measles models: a comparative numerical study.
Recurrent epidemics of measles in developed countries offer a proving ground for current theories of complicated dynamics in ecological and epidemiological systems. This paper contrasts the basic forced SEIR model for measles with a variety of more complicated and realistic models, showing that variations in seasonal forcing and age-structured mixing patterns can generate a wide range of global dynamics. The well-known chaotic dynamics of the forced SEIR model appear to be absent from more realistic models, suppressed by the buffering effect of a low-risk group of pre-school children. These results, and the variety of measles dynamics seen in real populations with different demographic and geographic patterns, point out the need for age- and spatially-structured measles models and suggest caution in the construction of models for complicated systems.
Department of Zoology, Cambridge University, UK.
B
B
Bolker
D000367:Age Factors; D002648:Child; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008433:Mathematics; D008457:Measles / Q000453:epidemiology* / Q000276:immunology / Q000635:transmission; D015233:Models, Statistical; D012621:Seasons