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 . 
<triplet> Disease ecology <subj> ecology <obj> subclass of <triplet> Disease ecology <subj> ecology <obj> subclass of