Principles of diseases chapter 14 – Flashcards

is an organism that shelters and supports the growth of pathogens

A normal state in which part or all of the body is not properly adjusted or is incapable of performing normal functions

Disease causing microorganisms

the invasion and growth of pathogens in the body

the scientific study of disease

eitiology (cause), pathogens (development) and effects of disease.

are usually germfree in utero

in and on the surface of the body soon after birth

involve close physical contact between the host

and source of the disease

 are microbes that are present for various periods

and then disappear

is where

Normal microbiota can prevent pathogens

from causing and infection

Normal Microbiota and the host living together

commensalism (one organism benefits and the other is unaffected)

mutualism (both organisms benefit)

Parasitism (one organism benefits and one is harmed)

Do not cause disease under normal conditions

but

can cause disease under special conditions

In some situations,

one microorganism makes it possible for another to

cause a disease or produce more severe symptoms

;

are criteria for establishing that specific microbes cause specific diseases.

1.  the same pathogen must  be present in every case of the disease.

2. the pathogen must be isolated in pure culture.

3. the pathogen isolated from pure culture must cause the same diseasein healthy, susceptible laboratory animal

4. The pathogen must be reisolated from the inoculated laboratory animal.

;

1.; modified to establish etiologies of diseases caused by viruses and some bacteria, which cannot be grown on artificial media

;

2.; Some diseases, such as tetanus, have unequivocal signs and symptoms.

;

3.; Some diseases, such as pneumonia and nephritis, may be caused by a variety of microbes

;

4.; Some pathogens, such as S. pyogenes, cause several different diseases.

;

5.; Certain pathofens, such as HIV, cause disease in humans only

;

;

A patient exhibiting subjective changes in body functions

;

Measurable changes in a patients body functions

;

;

Identification of the disease

;

made by a physician

;

;

A group of symptoms or signs

;

that always accompanies a specific disease

;

;

Are transmitted directly or indirectly

;

from

;

one host to another

;

;

is one that is easily spread

;

from

;

one person to another

;

Are cause; by microorganisms that normally grow outside

;

the human body

;

and are not transmitted

;

from one host to another.

;

incidence (number of people contracting the disease)

;

and

;

prevalence (number of cases at a particular time)

1.; sporadic

(disease occurs occasionally i.e. typhoid fever)

;

2.; endemic;

(disease is constantly present i.e. common cold)

;

3.; epidemic;

(a given area, acquire disease in a;relative short period of time i.e. AIDS, ghonerrhea);;;

;

4.; pandemic

(An epedemic disease that occurs worldwide i.e. influenza/AIDS)

;

;

1.Acute

;

2.chronic

;

3.subacute

;

or

;

4.latent

;

;

One that develops rapidly but lasts only a short time (influenza)

;

develops more slowly

bodys reactions may be less severe

disease likely to continue or recur for long periods

(hepatitis B)

;

;

A disease that is between acute and chronic

(sclerosing panencephalitis)

;

;

a continual source of infection

;

one in which the causitive agent remains inactive for a time,

;

then becomes active to produce symptoms of the disease

;

(shingles - caused by varicella virus)

;

;

;

;

;

presence of immunity to a disease in a most of the population;in a community.;

(example vaccination)

;

affects a small area of the body

;

affects a small area of the body

;

is spread throughout the body via

;

the circulatory system

;

;

;

is an acute infection that causes the initial illness

;

can occur after the host is weakened

;

;from a primary infection

;

(Pneumocystic pneumonia as a consequence of AIDS)

;

;

does not cause any signs of disease in the host

(poliovirus or hepatitis A virus)

;

;

a toxic inflammatory condition arising

;

from the spread of microbes,

;

especially bacteria or their toxins

;

from a focus of infections

;

blood poisoning, is a systemic infection

;

arising from the multiplication of pathogens in the blood.

;

;

presence of toxins in the blood (as occurs in tetanus)

;

;

;

;

refers to the presence of viruses in the blood

;

1.there must be a reservoir for infections as a source of pathogen

2.the pathogen must be transmitted to a susceptible host by direct contact, by indirect contact or vectors

3.; transmission is followed by invasion, in which the; microorganism enters the host and multiplies

4. following invasion the microorganism injures the host through a process called pathogenesis

5. extent of injury depends on the degree to which host cells are damaged, either directly or by toxins

6. The occurence of disease ultimately depends on the resistance of the host to the activities of the pathogen

;

;

;

;

people that have a disease or

are carriers of a disease

;

are diseases that affect wild and domestic animals and

can be transmitted to humans

(west nile virus)

;

;

Soil and water

;

can occur after the host is weakened from primary infection

;

constitutes indirect contact

;

Transmission by medium

by water, food or air

;

transmission via saliva, mucus in coughing or sneezing

;

any infection that is acquired during the course of a hospital stay.

;

;

5 - 15%

are new diseases with increasing incidences

;

the use of antibiotics,

;pesticides,

climactic changes,

travel,

the lack of vaccinations

and improved case reporting

analyzes a particular disease to determine probable cause

;

or

;

group of infected people is compared with and

uninfected group of people

;

;

controlled experiments designed

to test hypotheses are performed

;

provides data on incidence and prevalence to local, state and national health officials.

Mechanical transmission

transmission of pathogens by incests feet or body parts

;

;

biological transmission

athropod bites and infected person or animal

;

makes the body more susceptible to disease

;

(gender is sometimes a predisposing factor - ie. bladder infections)

;

the need of bacteria to cause disease