Ecological and evolutionary effects of fragmentation on infectious disease dynamics

• DOI: 10.1126/science.1253621
• Publication Date: 2014-06-12T18:16:10Z
• Authors: Jussi Jousimo; Ayco J. M. Tack; Otso Ovaskainen; Tommi Mononen; Hanna Susi; Charlotte Tollenaere; Anna-Liisa Laine
• Keywords: ta113; 0301 basic medicine; ta114; [SDV]Life Sciences [q-bio]; FINLANDE; 15. Life on land; 3. Good health; [SDV] Life Sciences [q-bio]; [SDE.BE] Environmental Sciences/Biodiversity and Ecology; 03 medical and health sciences; ta318; [SDE.BE]Environmental Sciences/Biodiversity and Ecology; ta116; ta515; ta217

Many connections are not always bad for health

Contrary to expectations, highly connected populations can experience less impact from infectious disease than isolated groups. What happens to pathogens in natural populations has been poorly studied, because they rarely cause devastating disease outbreaks. Thanks to a long-term study of an inconspicuous fungal-plant disease system, we have now gained some surprising insights. During a 12-year study, Jousimo et al. discovered that clustered and linked host-plant patches showed lower levels of fungal damage and higher fungal extinction rates than more distant patches (see the Perspective by Duffy). This phenomenon is explained by high gene flow and rapid evolution of host resistance within the connected patches. Populations of the modest weed Plantago , growing on the Åland Islands in the Baltic, were less than 10% infected by the Podosphaera mildew fungus in any given year, but infection turnover was high. These findings have broad implications for ecology, disease biology, conservation, and agriculture.

Science , this issue p. 1289 ; see also p. 1229