Lecture: Intro to Parasitology Flashcards
The science that deals with the study of living organism that depends on another organism for the purpose of procuring food and securing protection.
Parasitology
Organisms that obtain its food and shelter from another organism and derive all the benefits from the association.
Parasites
Organism that provides physical protection and nourishment to the parasites.
Host
Harbors the adult/sexual stage of the parasites.
Final or Definitive Host
Harbors part or all the larval stages of the parasites.
Intermediate Host
Harbors the early larval stages of the parasites.
First Intermediate Host
Harbors the infective larval stage of the parasite.
Second Intermediate Host
These hosts ensure the continuity of the life cycle of the parasites and act as additional source of infection.
Reservoir Host
Harbors the parasite in an arrested state of development. However, the parasite is capable of continuing its life cycle in a suitable host.
Paratenic Host
A process by which one organism, the parasite, living for or part of its life cycle on or within another, the host, obtains its energy or sustenance from the latter while producing effects that range from no demonstrable effect to severe pathology and death.
Parasitism
A close association between two organisms that is permanent wherein one cannot exist independently.
Symbiosis
An association that is beneficial to both the parasites and the host in which one can still survive even without the other.
Mutualism
Only the parasite benefit from the association while the host is unaffected.
Commensalism
Factors Affecting Transmission of Parasites
The source of infection
An effective mode of transmission and portal of entry
The presence of a susceptible host
Successful entry of the infective stage of the parasite
These parasites require further development in the soil before they become infective.
Soil-Transmitted Group (Soil-Transmitted Helminths, STH)
These group requires further development within the body of snail which serves as their intermediate host before they can become infective.
Snail-Transmitted Group
Some species of insects act as vectors of parasitic diseases such as mosquitoes, sandfly and Tsetse fly
Arthropod-Transmitted Group
Organisms that transmit parasites to man and may serve as intermediate host or definitive host to some parasite.
Vectors
Vector that is essential in the life cycle
Biological Vector
Vector that is inessential in the life cycle
Mechanical/Phoretic Vector
These group requires further development in the flesh of some animals that man consume.
Animal/Food-Transmitted Group
Person to person transmission, wherein the parasites require no further development and are readily infective.
Contact-Transmitted Group
In this case, the infected person is his own source of re-exposure.
Autoinfection (One’s self)
Parasites that are ingested in its infective stage.
Cyst of Entamoeba histolytica
Embryonated egg of Ascaris lumbricoides
Trichuris trichiura
Parasite that is acquired by intimate oral contact/kissing.
Trichomonas tenax
Parasites that are acquired by active larval penetration/skin penetration.
Hookworms
Strongyloides
Schistosomes
Parasites that are acquired by bite of arthropod vector.
Plasmodium
Wuchereria
Parasites that are acquired through sexual intercourse (Genitals)
Trichomonas vaginalis
Entamoeba histolytica
Parasites that are acquired through inhalation (Nose/Intranasal Cavity)
Enterobius vermicularis
Naegleria
Parasites cross the placental barrier (Transplacental)
Toxoplasma gondii
The interval between exposure to the parasites and the appearance of the earliest signs and symptoms.
Clinical Incubation Period
The development of the parasite in a particular host and demonstration of the stages of the parasites in the different specimens.
Biological Incubation Period
The development of a parasite which involves the survival and development in the external environment and in one or more hosts.
Life Cycle
This method of diagnosis is based on the recognition of the characteristic signs and symptoms of the infection of disease.
Clinical Diagnosis
This method of diagnosis is based on the identification of the parasites in the different specimens.
Laboratory Diagnosis
The body of knowledge that concerns diseases in human population or communities rather than in individuals.
Epidemiology
When a disease in human population maintains a relatively steady, moderate level
Endemic
If there is a sharp rise in the incidence or an out-break of considerable intensity occurs.
Epidemic
If the prevalence of a disease in a community is high.
Hyperendemic
The disease covers extensive area of the world.
Pandemic
If it appears only occasionally in one or at most few members of a community.
Sporadic
Parasites that live within the body of the host.
Endoparasite
Parasites that live outside or on the surface of the body of the host.
Ectoparasite
Parasites that cause injury by its mechanical, traumatic or toxic activities.
Pathogenic
Parasites that derives benefits from the host without causing any considerable damage or harm.
Non-Pathogenic
Parasites that takes up a permanent residence and is completely dependent upon its host for existence throughout its life..
Obligate
Parasites that are capable of leading both free and parasitic existence under favorable or appropriate circumstances
Facultative
Parasites that establishes itself in a host in which it does not ordinarily lives.
Incidental
Parasites that are free living during part of existence and seeks only its host intermittently to obtain nourishment.
Temporary
Parasites that remains on or in the body of the host from early life to maturity.
Permanent
Parasites which parasitizes other hosts and recovered in a living or dead state from human excreta; no further development and do not cause injury or damage.
Spurious / Coprozoic
This is the common portal of entry of most intestinal parasites.
Mouth
Parasites that are part of Soil-Transmitted Helminths
Ascaris lumbricoides
Trichuris trichiura
Hookworms
Parasites that are part of Snail-Transmitted Group
Flukes (trematodes)
Parasites that need vectors
Plasmodium
Filarial worms (Wuchereria bancrofti)
Parasites found in raw pork
Trichinella spiralis
Taenia solium
Parasite found in raw beef
Taenia saginata
Parasites that are part of Contact-Transmitted Group
Enterobius vermicularis
Trichomonas vaginalis
Parasites that are part of autoinfection
Enterobius vermicularis
Strongyloides stercolaris
Some infected individual that do not show any signs and symptoms and are known as
Carrier
