Chapter 14 Test 4

Categorize diseases according to severity. (4)

1.Acute disease= one that develops rapidly but lasts only a short time; influenza, hep A 2. chronic disease: develops more slowly and the body's reactions may be less severe, but the disease is likely to continue or recur for long periods; TB, hep B 3. Subacute disease= a disease that is intermediate b/t acute and chronic. 4. Latent disease= a disease in which the CA remains inactive for a time but then becomes active to produce symptoms of the disease; shingles

Identify four predisposing factors for disease.

Gender, Genes, climate/wheather, and life style choices (nutrition, fatigue, exercise ect.)

Identify the function of the CDC

branch of the us public health service; is the central source of epidemiological info about the united states.

Compare commensalism, mutualism, and parasitism, and give an example of each.

commesnsalism= symbiotic relation in which one organism benefits and the other is unaffected. EX: some normal microbiota such as stapholococcus epidermis; does not harm host but benefits. Mutualism= symbiotic relationship in which both organisms benefit. EX: E.coli in the large intestine; synthesize Vitamine K and B and the large intestine provides nutrients to E.coli Parasitism= symbiotic relationship in which one organism benefits and the other is harmed. EX: disease causing bacteria, ticks, ect.

Give an example of contact transmission, vehicle transmission, mechanical transmission, and biological transmission.

contact transmission=, example of contact transmission: Person to person as in sexual intercourse, vehicle transmission Foodborne transmission (improperly prepared food), mechanical transmission (vector) A mechanical vector picks up an infectious agent on the outside of its body and transmits it in a passive manner. An example of a mechanical vector is a housefly. Biological (vector) harbor pathogens within their bodies and deliver pathogens to new hosts in an active manner, usually a bite.

Define reservoir of infection

continual source of the disease organism ex: humans, animal, or nonliving hosts

Distinguish the incidence from the prevalence of a disease.

incidence=# of people in a pop who develop a disease during a particular period (indicator of the spread of the disease) prevelence=the # of people in a pop who develop a disease at a specified time, regardless of when it first appeared.

Put the following in proper sequence, according to the pattern of disease: period of decline, period of convalescence, period of illness, prodromal period, incubation period.

incubation, prodromal, illness, decline, convalescence

compromised host

is one whose resistance to infection is imapaired by disease, therapy, or burns

Define the following terms: morbidity, mortality, and notifiable infectious diseases

morbillity; the incidence of specific notifiable diseases mortallity; the # of deaths from the disease.. notifiable infectious disease; diseases for which physicians are required by law to report

Define normal and transient microbiota.

normal microbiota=the body's MO's that establish less permanent residence(colonization) but DONT cause disease under normal conditions. Transient microbiota= are present for several days, weeks, or month, and then disappear.

Define disease

occurs when an infection results in any change from a state of health.

Explain three methods of disease transmission.

(contact=spread of disease by direct, indirect, or droplet transmission) contact-aka person to person, via physical contact indirect-agent is transmitted from resevoir to host via nonliving object tissues, desks ect. droplet transmission- coughing, sneezing, laughing.

List several probable reasons for emerging infectious diseases, and name one example for each reason.

*GENETIC RECOMBINATION new strains such as cholerae recombination *GLOBAL WARMING and change of weather patterns-malaria *TRAVEL known diseases such as west nile may spread to new areas *MIGRATION AND CHANGE IN ECOSYSTEM previously unrecognized infections b/c of- hemorrhagic fever *ANIMAL CONTROL-lyme disease increasing from killing animal predators

Categorize diseases according to frequency of occurrence. (4)

1. sporadic disease= if a disease only occurs ocaisionally. (ex: typhoid fever) 2. endemic disease= a disease constantly present in a population (ex: cold) 3. epidemic disease=many people in a given area aquire in a short period (ex: influenza, aids in america) 4. pandemic disease= an epidemic disease that occurs world wide. (ex: aids)

List Koch's postulates. Explain some exceptions to Koch's postulates.

1. the same pathogen must be present in every case of the disease 2. the pathogen must be isolated from the diseased host and grown in pure culture. 3. the pathogen from the pure culture must cause the disease when it is inoculated into a healthy suceptible laboratory animal. 4. the pathogen must be isolated from the inoculated animal and must be shown to be the original organism.

Define etiology

=pathology's first concern; the cause

Contrast normal microbiota and transient microbiota with opportunistic microorganisms.

Normal microbiota and transient microbiota contain MO's that can become opportunistic infections for example, E.coli. Access of MO's through broken skin and mucus membranes, ind. that are ill, have weakend immunde systems, aids/hiv, or are elderly are pathways to opportunistic infections.

What are the objectives of pathology? (4)

The cause or etiology of disease, pathogenesis the manner in which disease develops, the structural and functional changes brought by the disease, and their final effects on the body.

Define pathology

The scientific study of disease

What interacting factors result in nosocomial infections?

aquried in hospitals- factors= MO's in hospital, weakened immune system of host, and the chain of transmission in the hospital.

Differentiate a communicable from a noncommunicable disease.

communicable disease= a disease that spreads from one host to another, either directly or indirectly. EX: chick pox, herpes, TB (CONTAGIOUS) noncommunicable disease= is not spread from one host to another. EX: tetanus; produces disease only when introduced into the body via abrasions or wounds. they are diseases cause by opportunistic pathogenic MO's

Define herd immunity. How does herd immunity develop?

herd immunity= when many immune people exist in a pop. this works because when an ind. is immune to a disease, they act as a barrier for that disease. Additionally, they lower the occurrence because they limit the rapid spread to ind who are not immune/vaccinated.

Contrast human, animal, and nonliving reservoirs, and give one example of each. Why are carriers important reservoirs of infection?

human-people who are actively infected or carriers for a disease may pass the germs to another human EX: AIDs. animal-diseases that occur in animals can be transmitted to humans are called zoonoses. Ex: lymes disease and rabies. transmitted by contact with feces, contact with animal, and insect vectors. non living reservoirs- soil and water-botulism and tetanus

local, systemic, and fnocal infectio

local=MO's are limited to an area of body systemic= MO's or their products are spread throughout the body via blood or lymph focal=agents of a local infection that enter the body via blood or lymph and spread to systemic area

Define epidemiology, and describe three types of epidemiologic investigations.

science that studies when and where diseases occur and how they are transmitted. 1 descriptive epidemiology= entails collecting all data that describe the occurrence of the disease under study. 2 analytical epidemiology-analyzes a particular disease to determine its probable cause. 3 experimental epidemiology- begins with a hypothesis about a particular disease; experiments to test the hypthesis are then conducted witha group of peopl.

sepsis, septicemia, toxemia, bacteremia, and viremia

sepsis=toxic inflammatory condition septicemia= aka blood poisoning bacteremia= presence of bacteria in the blood toxemia= presence of toxins in the blood viremia= presence of a virus in the blood

Define infection

the invasion or colonization of the body by pathogenic MO