Disease ecology

Disease ecology is a sub-discipline of ecology concerned with the mechanisms, patterns, and effects of host-pathogen interactions, particularly those of infectious diseases, within the context of environmental factors Disease ecology operates under the assumption that host-pathogen interactions can be conceptually united with other interspecific interactions, such as predation or parasitism.

While the field is often defined within the context of ecology as a whole, disease ecology relates ideas from a wide variety of medical and biological disciplines including immunology, epidemiology, and genetics.

Interactions in Disease Ecology[edit]

Parasitism in disease ecology is important because it can shape the way many habitats function because they are disease carriers. These diseases can alter the timing of events, biogeochemical cycles, and even the flow of energy in a habitat. Parasites are able to limit population growth and reproduction of species which may lead to a shift in the balance of an ecosystem.  Other ways parasites impact systems are through nutrient cycles. Parasites are able to create imbalances of the elements in a system through the relationship they have with a host and the host’s diet. In some cases when a parasite has weakened an animal it will become easier prey for a predator species.

Occasionally predators will prefer feeding on the sick or infected prey even though they carry a parasite because of the opportunity weak prey present. Without the presence of a predator species the prey species would likely exceed manageable numbers therefore leading to the rapid spread of pathogens throughout the prey population. Available host numbers increased when the infected individuals are not removed due to low predation. However, there are some situations where predator feeding can disturb a pathogen that previously was dormant leading to an epidemic that otherwise would not have occurred. Some parasites are able to survive when their host species is consumed leading to the parasite being distributed in the waste of the predator which can continue the spread of disease.