Exam 3: Study Guide Ch. 14/15 DONE

Question 1

Explain what microbiota is and the role it plays in the human body

Answer 1

o Microbiota: Microbes that reside in the body without causing disease
o The role it plays in the body is that it resides in certain sections but if those microbes were to leave their spot they could cause great harm

Question 2

Define pathogen, pathology, pathogenesis, etiology, infection and disease.

Answer 2

o Pathogen: agent of disease
o Pathology: scientific study of disease
o Pathogenesis: manor in which a disease develops
o Etiology: cause of disease
o Infection: invasion, multiplication and colonization of pathogenic microorganisms in the body
o Disease: any change from the general state of good health into an abnormal state

Question 3

Define virulence and explain how microorganisms may have it.

Answer 3

o Virulence: Degree of pathogenicity
o Microorganisms have it due to
 Capsules
 Components of the cell wall that increase adhesion
 Enzymes released to the environment
 Toxins:
* Exotoxins
* Endotoxins (part of bacterial envelope)

Question 4

• List the different sources of infection and define what a reservoir is.

Answer 4

o Diseased human
o Human Carrier (had it, recovered, still contagious)
o Animals (zoonoses)
o Non-living environment
o Self (our own microbiota; moving from where it’s supposed to be)
o Reservoir: Source of infection
 Can be living organism or inanimate object that provides a pathogen with conditions for survival and multiplication and transmission

Question 5

Define resistance, susceptibility, compromised host and human carrier.

Answer 5

o Resistance: ability of the host to ward off disease
o Susceptibility: vulnerability to a disease (lack of resistance)
o Compromised host: resistance is impaired by disease, therapy or burns
o Human carrier: recovered from the disease by continue to shed the disease agents

Question 6

Differentiate between an exogenous and an endogenous infection.

Answer 6

o Exogenous infection: occurs if a pathogen breaches the hosts external defense and enters sterile tissue
o Endogenous Infection: occurs if normal microbiota enters sterile tissue

Question 7

Explain what a subclinical and a nosocomial infection is.

Answer 7

o Subclinical Infection: No noticeable illness but you have the illness
o Nosocomial infection: serious health threats within the healthcare system; getting sick from going to the hospital for something else and picking up germs

Question 8

Describe the progression of a disease and list the different stage.

Answer 8

o Incubation period: time between entry of microbe and when symptoms appear
o Prodromal phase: a time of mild signs or symptoms
o Acute period (Climax): period of full illness, when signs and symptoms are most intense
o Period of decline: when signs and symptoms subside
o Period of convalescence: when body systems return to normal

Question 9

Differentiate between signs and symptoms of a disease.

Answer 9

o Signs: things that can be measured (blood sugar/pressure, temp, etc.)
o Symptoms: things that can’t be measured by can be described by the patients to be associated (headache, nausea, stomach pain, etc.)

Question 10

Explain what a syndrome is.

Answer 10

o Syndrome: collection of signs and symptoms that together are characteristics of a disease

Question 11

Define portal of entry, portal of exit and infectious dose.

Answer 11

o Portal of entry: route an exogenous pathogen uses to enter the body (must enter with a certain number (infectious dose)
o Portal of exit: route an exogenous pathogen uses to exit the body
o Infectious dose: number of microbes entering the body that can establish an infection

Question 12

Differentiate between bacteremia, septicemia, toxemia, fungemia, viremia and parasitemia

Answer 12

o Bacteremia: presence of bacteria in blood
o Septicemia: bacteria multiplying in blood (infection)
o Toxemia: presence of toxin in blood
o Fungemia: presence of fungi in blood
o Viremia presence of viruses in blood
o Parasitemia: presence of parasites in blood

Question 13

Define epidemiology and list the elements that an epidemiologist determines.

Answer 13

o Epidemiology: Scientific study of the causes, transmission and prevention of disease
o Determine:
 Etiology
 Factors or patterns concerning persons affected
 Source and mode of transportation
 Time period
 Incidence: Fraction of the population that contracts the disease in a period of time
 Prevalence: Fraction of the population having the disease at a specified time

Question 14

List and define the different types of diseases.

Answer 14

o Communicable disease: transmittable among hosts in a population
 Contagious-easily spread
o Non-communicable: not transmitted to another host
 They are acquired directly from the environment
o Heredity: Passed though genes
o Degenerative: develops changes in the structure of tissues and organs with consequence of lack of function
o Infectious: caused by a microorganism
o Acute disease: develops rapidly, causes severe symptoms, fades quick
o Chronic disease: linger for long periods of time and are slow to develop and recede
o Subacute: intermediate between acute and chronic
o Latent: Causative agent remains inactive for a period of time but then becomes active to produce symptoms of disease

Question 15

List and define the terms used to describe the frequency in which is disease is found in a population.

Answer 15

o Sporadic: Occasional
o Endemic: Habitually or constantly present at a low level in a certain geographic area
o Epidemic: many people in a given area acquire a disease in a short period of time
o Outbreak: think contained epidemic
o Pandemic: is a worldwide epidemic

Question 16

Describe the role of the Centers for Disease Control in the United States.

Answer 16

o Case reporting: Health care workers report specified disease to local, state, and national offices
o Nationally notifiable diseases: Physicians are required to report occurrence.
o Morbidity: Incidence of a specific notifiable disease.
o Mortality: Deaths from notifiable diseases.
o Morbidity rate: Number of people affected in relation to total population in a given time period.
o Mortality rate: Number of deaths from a disease in relation to total population in a given time period

Question 17

Define symbiosis and list and explain the three types of symbiosis

Answer 17

o Symbiosis: mutually beneficial relationship; live in body without causing disease
o Types:
 Mutualism: Both host and microbe benefit
 Commensalism: Microbe benefits and the host is unaffected

Question 18

List and define the different types of pathogens and infection, and how they may differ in their behavior.

Answer 18

o Primary pathogen - cause disease in the population in general (i.e. occur in otherwise healthy bodies)
o Secondary (a.k.a. opportunistic) cause infections in a body weakened by a primary infection or otherwise compromised host
o Local infections are restricted to a single area of the body
o Systemic or generalized infections disseminate to organs and systems

Question 19

Differentiate between emerging and re-emerging diseases and explain what have led to their development.

Answer 19

o Emerging: new or changing diseases (Covid)
o Re-emerging: resurgent diseases (came back either because people didn’t get vaccines, or they just stopped working

Question 20

List the different routes of transmission as well as the different ways in which infectious agents may be transmitted.

Answer 20

o Routes of Transmission
 Coughing/Sneezing
 Through an open lesion
 In urine
 Through blood
 By an insect bite
 In feces
o Infectious agents may be transmitted
 Direct contact
 Indirect contact
 Common vehicle Airborne
 Vectors