parasitology Flashcards
ectoparasite
lives on the outer surface of its host
endoparasite
lives inside its host
facultative parasite
establishes a relationship with a host if the opportunity presents itself
obligatory parasite
physiologically and metabolically dependent on the host, can only survive with host
aberrant parasite
characteristic of the host (often found with the host), but found in an unusual location within the host
accidental/incidental parasite
found on a host other than its normal host
definitive host
one in which the parasite reaches sexual maturity, or the most important host. if no sexual reproduction occurs
intermediate host
one in which some developmental/asexual reproduction occurs, but sexual maturity does not occur
reservoir host
a “living source” of the parasite; not a host of primary concern
vector
intermediate host that actively transmits a disease organism (usually an arthropod), is required for the life cycle of the parasite
direct life cycle (monoxenous parasite)
involves only a single host, commonly called “hand-to-mouth” cycles
indirect life cycle (heteroxenous parasite)
involves two or more hosts
epidemiology
literally means “as it falls upon the people.”
working definition is the ecology of disease/study of disease ecology
includes all aspects of the pathogen, host(s), environment, social conditions, etc. that contribute to, or influence the maintenance of, a disease
endemic
a disease pathogen is present in an area and is expected to be there
epidemic
the presence of a disease is at levels higher than what normally is expected
pandemic
an epidemic that is worldwide in scope
etiologic agent
the causative agent of a disease
neglected tropical diseases (NTD)
diseases that generally don’t attract the interest or funding that are directed toward diseases of more affluent populations
affect more than one billion people particularly those living in poverty
zoonosis/zoonotic disease
a disease that exists in non-human animals, but can and does spread to humans
incidence
number of new cases of infection (disease) in a given time period divided by number of infected and susceptible hosts at the beginning of the time period
intensity
number of parasites in a given host
mean intensity
total number of parasites recovered, divided by the number of infected hosts in a given population
density
number of parasites per unit area, weight, or volume of tissue (e.g., number of parasite eggs per gram of feces)
prevalence
number of infected hosts, divided by the number of hosts examined at a point in time
overdispersed
parasite infections where relatively few hosts harbor the majority of all parasites in a population
underdispersed
population of hosts that all have a relatively similar number of parasites
hematophagous arthropod
animals (normally insects/tics) that feed on the blood of other animals
commonly actively transmit pathogens
vector competence
ability of a vector to support development and/or replication of a pathogen
demands physiologic and genetic compatibility between vector and pathogen
extrinsic incubation period
time it takes for the pathogen to develop from the time it was taken up to the time it was transmitted
anthropophilic/anthropophagic
having an attraction to, or preference for, humans
organisms that feed on humans
ornithophilic
having an attraction to, or preference for, birds
mammalophilic/zoophilic
having an attraction to, or preference for, mammals/animals
diurnal
organisms that feed during the day