Sick animals isolate themselves, limit disease transmission

ZURICH, Switzerland, Aug. 22 (UPI) -- New research suggests sick animals protect the health of their social group by isolating themselves.

Scientists have previously documented the ways wild animals change behavior when they get sick, though previous research efforts have mostly ignored the effects of illness and social interactions.

In a recent study involving wild house mice, researchers found sick specimens became less active and isolated themselves. Scientists triggered an immune response and generalized symptoms by injecting specimens with a lipopolysaccharides, part of a bacteria cell wall.

Previous studies have shown mice can detect when another mouse is sick, but in the most recent experiment, other mice continued to interact with sick specimens as they normally would.

"It was the sick mouse that removed itself from the group," Patricia Lopes, an evolutionary biologist at the University of Zurich, said in a news release.

Researchers used their observations to inform a mathematical model designed to predict the spread of disease. The model suggests self-isolating mice help limit the spread of disease to their social group and their family.

"When we account for the behavioral changes and how they affect social contacts, we find that the speed and the extent of disease spread are greatly reduced," Lopes explained.

By studying how group dynamics among wild mice affect the spread of disease, researchers hope to develop better models for predicting the spread of disease among human populations.

Lopes and her colleagues published their latest research this week in the journal Scientific Reports.