Summary
International Symposium on Nonlinear Theory and its Applications
2010
Session Number:A1L-A
Session:
Number:A1L-A4
Why scale-free networks are a good thing for controlling disease transmission
Michael Small,
pp.11-14
Publication Date:2010/9/5
Online ISSN:2188-5079
Summary:
The observation of a scale free degree distribution in real disease incidence data tends to suggest that such diseases would be difficult, or in fact impossible to control. Moreover, it has been shown that the fat tail degree distribution for scale free networks implies that (SIS type) disease transmission cannot be eradicated for any nonzero level of infectivity. Nonetheless, we have found that when one considers a voluntary immunisation strategy, or even, disease transmission in multiple waves, the presence of hub nodes actually becomes an advantage. Highly connected nodes will be immunised earlier (or conversely, quickly encounter an early and less virulent strain of infection). As a consequence of the frailty of scale-free networks, the removal of hub nodes will actually reduce the infectivity of the disease. In this paper we consider disease transmission on scale free networks and on more stratified networks, motivated by structures observed in society. We find that the level of infection for scale free networks is actually only moderately higher than for equivalent structured networks. Nonetheless, in finite size networks extinction occurs at a higher threshold for structured (non-scale free) networks. Conversely, these structured networks exhibit broader (in time) peaks in the disease outbreak.