Different animals have distinct ways of socially dealing with contagious diseases depending on their social nature.
Spiny lobsters are very social: denning in groups of 20. Homes in corals, sponges, or rocky crevices on the ocean floor are havens against predators such as triggerfish.
These lobsters are victimized by a virus which kills over half the juveniles it infects. Sick lobsters self-isolate: denning solo until they either recover or die. Healthy lobsters shun sick ones.
Eusocial insects, such as ants and honeybees, know well enough the toll contagious sickness might take on their colony. Forager ants or bees who fall ill self-isolate. As a precaution, foragers who are not sick, but know that an infectious disease is about, reduce their social interactions, and are especially wary for essential workers: the queen and brood nurses.
Birds generally avoid other birds that are sick. But the degree of wariness varies. Birds know their health status. Those with robust immune systems are less cautious than weaker ones.
Guppies, and perhaps other social fish, shun others of their kind that are sick. Like birds, fish know their fitness and exercise more or less caution depending upon their personal health.
Social ties are important to simians. Grooming is the typical way relations are kept close. Like other simians, mandrills avoid grooming the sick unless they are a close relative or vital social connection.
Mongooses are gregarious. Ones in Botswana are subject to a contagious tuberculosis that takes months to kill them. Healthy mongooses do not shun sick ones, which are groomed to the same extent – even though sick mongooses are far less likely to reciprocate. Social distancing may simply be infeasible in species which rely upon close cooperation.
Valerie A. Curtis, “Infection-avoidance behaviour in humans and other animals,” Trends in Immunology (October 2014).
Dana M. Hawley & Julia C. Buck, “Animals apart,” Scientific American (August 2020).
J.C. Buck et al, “Ecological and evolutionary consequences of parasite avoidance,” Trends in Ecology & Evolution (August 2018).