Lecture 2 ANI SCI 320 : Introduction to Infection

Question 1

What is the ratio of human cells to colonizing cells?

Answer 1

1:1

Question 2

What is normal flora?

Answer 2

Microorganisms that normally reside at a given site and under normal circumstances do not cause disease

Question 3

What are 2 reasons why normal flora is essential for health?

Answer 3

1. Creates an environment that may prevent infections
2. Enhances most human defenses

Question 4

Why do we say that internal organs, tissues, and fluid are relatively microbe free?

Answer 4

Because most organs are meant to be microbe free but this can be disrupted with injuries and medical proceedures?

Question 5

What are the 2 types of flora?

Answer 5

1. Transient Flora
2. Resident Flora

Question 6

What is transient flora?

Answer 6

Flora that only occupies the body for short periods and that is picked up during daily activities, and is often eliminated very easy

Question 7

What is resident flora?

Answer 7

Resident flora are permanently established flora for long periods of time.

Question 8

What is the mutualism relationship with microbiome? Give an example.

Answer 8

Relationship where both the host and microbe benefit
EX : Ruminants and their gut microorganisms

Question 9

What is the commensalism relationship with microbiome?

Answer 9

One partner benefits and the other neither benefits nor is harmed?

Question 10

What is the parasitism relationship with microbiome?

Answer 10

One organism benefits and the expense from the host

Question 11

What do external parasites cause?

Answer 11

Infestation

Question 12

What do internal parasites cause?

Answer 12

Infection

Question 13

What is the pathogenic relationship with microbiome?

Answer 13

Organism that causes damage to the host during infection. The worst relationship.

Question 14

When does initial colonization happen for humans?

Answer 14

The uterus and contents normally are sterile and remain so just until birth.

Question 15

What has a large impact on an infants gut microbiome?

Answer 15

Mode of birth

Question 16

What is sterile womb paradigm?

Answer 16

Fetus and placenta are sterile. The gut microbiome is acquired after birth.

Question 17

What is in utero colonization hypothesis?

Answer 17

Placenta harbors its microbiome. Colonization of the gut begins in utero

Question 18

What are 6 factors that influence maternal initial colonization?

Answer 18

1. Gut microbiota
2. Vaginal Health
3. Genetics
4. Diet
5. Antibiotics
6. Periodontal Disease

Question 19

What are 5 postnatal factors that influence initial colonization?

Answer 19

1. Genetics
2. Breastfeeding v Formula Milk
3. Medications and Antibiotics
4. Diet
5. Environment

Question 20

What are the 6 infectious agents?

Answer 20

1. Viruses
2. Bacteria
3. Fungi
4. Protozoa
5. Worms
6. Prions

Question 21

What is an infection?

Answer 21

Condition in which infectious agent penetrates host defenses

Question 22

What is an infectious disease?

Answer 22

An infection that causes damage or disruption to tissues and organs and or physiological homeostasis

Question 23

What are endogenous infections?

Answer 23

Occurs when normal flora is introduced to a site that was previously sterile

Question 24

What are exogenous infections?

Answer 24

Infections caused by organisms that are not normally present in the body, but have gained entrance from the environment

Question 25

What are the two types of pathogens?

Answer 25

1. True Pathogen
2. Opportunistic Pathogen

Question 26

What is a true pathogen?

Answer 26

Infectious agent that causes disease in virtually any susceptible host

Question 27

What is a opportunistic pathogen?

Answer 27

Normally harmless, but causes disease when the normal flora is disrupted or when the host is immunocompromised

Question 28

What are the 3 patterns of infection?

Answer 28

1. Localized
2. Systemic
3. Focal

Question 29

What is a localized infection?

Answer 29

Infectious agent that enters the body and remains confined to a specific tissue

Question 30

What is a systemic infection?

Answer 30

Infection that spreads to several sights and tissue fluids, usually in the bloodstream

Question 31

What is a focal infection?

Answer 31

Infectious agent breaks loose for a local infection and is carried to another tissue

Question 32

What are the three patterns of infection?

Answer 32

1. Mixed infection
2. Primary Infection
3. Secondary infection

Question 33

What is a mixed infection?

Answer 33

Several microbes grow simultaneously at the infection site

Question 34

What is a primary infection?

Answer 34

Refers to the first time you are exposed to a specific pathogen

Question 35

What is a secondary infection?

Answer 35

Another infection by a different microbe, succeeding a primary infection

Question 36

What are the three things that define a disease?

Answer 36

1. Signs
2. Symptoms
3. Syndrome

Question 37

What is a sign? Is it objective or subjective?

Answer 37

Objective

Something that can be detected and measured by someone else

Question 38

What is a symptom?

Answer 38

Something that must be described by the one suffering the disease

Question 39

What is a syndrome?

Answer 39

The complete set of signs and symptoms associated with a specific disease

Question 40

What is an acute infection?

Answer 40

Comes on rapidly, with severe but short lived effects

Question 41

What is a chronic infection?

Answer 41

Infection that progresses and persists over a long period of time

Question 42

What is an asymptomatic infection?

Answer 42

Although infected the host does not show signs of disease

Question 43

What is communicable infection?

Answer 43

Infected host can transmit the infectious agent to another host

Question 44

What is a non-communicable infection?

Answer 44

Infection does not arise through transmission from host to host

Question 45

What nosocomial infections?

Answer 45

Infections acquired or developed during hospital stay