Definition of Quarantine

Today is our topic of discussion Definition of Quarantine

Definition of Quarantine

Definition:

It is the limitation of freedom of movement of such well persons or domestic animals exposed to communicable disease for a period of time not longer than the longest usual incubation period of the disease, in such manner as to prevent effective contact with those not so exposed.

Advantage:

Quarantine helps to limit the spread of the disease and thus makes control measure easy.

Notification

Definition:

An official report notifying an appropriate authority of the occurrence of a specified communicable or other disease in humans or in animals.
Example – Acute flaccid paralysis (AFP) in suspected polio. Diseases in humans are reported to the local health authority and those in animals to the veterinary & livestock department. Few diseases in animals, also transmissible to humans, are reportable to appropriate (both health & livestock) authorities; such as anthrax.

Advantage:

It helps to initiate prompt action by the appropriate authority for control measure.

Vector

Definition:

A ‘vector’ is defined as an arthropod or any living carrier (e.g. pet) that transports an infectious agent to a susceptible individual.

Types of vector:

Biological vector:

An arthropod vector in whose body the infecting organism develops or multiplies before becoming infective to the recipient individual. Example – Haematophagous (feeding on blood) arthropods such as mosquitoes (e.g. plasmodium) and other biting insects such as sandfly (LD body).

Mechanical vector:

An arthropod vector which transmits an infective organism from one host to another but which is not essential to the life cycle of the parasite. Example – Flies for transport of amoebal cysts.

Host

Definition:

A person or other animal, including birds and arthropods that afford subsistence or lodgment to an infectious agent under natural conditions.

Types of host:

Definitive/primary host –

A definitive host is an organism that hosts the adult (sexual) form of the parasite or the host in which the parasite attains maturity.
Example: Sandfly for promastigote form of the protozoa Leishmania donovani, mosquito for plasmodium (malarial parasite).

Obligate host

means the only host. Example: Man in measles and typhoid fever.

Intermediate/secondary host –

An intermediate host is an organism that hosts the larval/asexual form of the parasite. Humans for amastigote form of the protozoa Leishmania donovani, man for malarial parasite.

Transport/paratenic host

is a carrier in which the organism remains alive but does not undergo development.
Example: Humans can act as paratenic hosts to dog roundworm by ingesting eggs (which contain already fully-developed larvae) contained in infested dog’s feces. The larvae can hatch, survive and migrate in the human body, but do not develop further.

Reservoir host:

A host that serves as a source of infection and potential reinfection of humans and as a means of sustaining a parasite when it is not infecting humans.
A reservoir host can harbour pathogen indefinitely with no ill effects. A single reservoir host may be reinfected several times. Example – Humans for gonococci & sheep, cattle, horses and humans are for some trypanosoma species.

Dead-end/incidental/accidental host:

It is an intermediate host that generally not allows transmission to the definitive host, thereby preventing the parasite from completing its life cycle. For example, humans are dead-end hosts for Echinococcus tapeworms.

As infected humans are not usually eaten by dogs, foxes etc. Although it causes serious disease in the dead-end host – is unable to infect the primary host and so mature]