Scientists have found that sick wild bats spend less time with their relatives. This slows down the rate at which the disease spreads.
As the pathogen spreads through the population, changes in social behavior can affect the spread of the disease. The transmission rate can increase when parasites change the host’s behavior, or decrease when healthy people avoid sick people.
The researchers conducted an experiment to study how the behavior of animals changes during illness. Scientists caught 31 adult female bats, and then simulated the disease within the group. To do this, the researchers injected randomized half of the bats with an immunity-inducing substance, lipopolysaccharide, while the control group received saline injections.
The researchers then glued the proximity sensors to the subjects for three days and released them back. During the experiment, scientists observed 16 “sick” bats and 15 bats from the control group in vivo.
Compared to control bats, the “sick” ones spent less time with others and were less socially associated with healthy individuals. During the treatment period, the sick bats spent 25 minutes less communicating with each partner. These differences diminished after the bats recovered.