Number of individuals (determined directly of indirectly) of a particular parasite species in each infected host (i.e., in a infrapopulation) in a sample. Frequently expressed as a numerical range.
Margolis L, Esch GW, Holmes JC, Kuris AM, Schad GA (1982) The use of ecological terms in parasitology (report of an ad hoc committee of the American Society of Parasitologists). J Parasitol 68:131–133