Relationship between population density and viral infection: A role for personality?

Ecol Evol. 2019 Aug 18;9(18):10213-10224. doi: 10.1002/ece3.5541. eCollection 2019 Sep.

Abstract

Conspecific density and animal personality (consistent among-individual differences in behavior) may both play an important role in disease ecology. Nevertheless, both factors have rarely been studied together but may provide insightful information in understanding pathogen transmission dynamics. In this study, we investigated how both personality and density affect viral infections both direct and indirectly, using the multimammate mice (Mastomys natalensis) and Morogoro arenavirus (MORV) as a model system. Using a replicated semi-natural experiment, we found a positive correlation between MORV antibody presence and density, suggesting that MORV infection is density-dependent. Surprisingly, slower explorers were more likely to have antibodies against MORV compared to highly explorative individuals. However, exploration was positively correlated with density which may suggest a negative, indirect effect of density on MORV infection. We have shown here that in order to better understand disease ecology, both personality and density should be taken into account.

Keywords: Mastomys natalensis; Morogoro virus; animal personality; arenavirus; density; density dependence; disease ecology; exploration; multimammate mice; stress sensitivity.