CH5 - Infection

Question 1

A state of tissue destruction resulting from invasion of microorganisms:

Answer 1

Infection

Question 2

Any microorganisms that can cause a disease ➡️ must be able to bind to human host cells

▫️directly destroys host cells
▫️interferes host cells metabolic capabilities
▫️exposes host cell to toxins

Answer 2

Pathogens

Question 3

pathogenicity- qualities that allow microorganism to promote a disease.

Answer 3

▫️virulence
▫️infectivity
▫️toxigenicity
▫️antigenicity
▫️antigenic variability 
▫️pathogenic defense mechanisms

Question 4

The majority of _____ are harmless to humans and may even be beneficial to our lives ➡️ could not survive w/o them

▫️antibiotic
▫️insulin
▫️food industry: in bread making, yogurt, cheese

Answer 4

Microorganisms

Question 5

The beneficial population of microbes (bacteria, viruses, Protozoa) that live in and on our bodies
▫️nose, pharynx 
▫️mouth, colon, rectum
▫️vagina
▫️distal urethra and perineum

Answer 5

Normal flora

Question 6

Manifestation of infection - Systemic

Answer 6

▫️fever
▫️weakness 
▫️headache
▫️malaise 
▫️anorexia
▫️nausea

Question 7

Manifestation of infection - Local

Answer 7

▫️heat
▫️incapacitation
▫️Pain 
▫️edema
▫️redness
▫️lymphadenitis
▫️purulent exudate

Question 8

Classes of microorganisms

Answer 8

▫️bacteria
▫️viruses
▫️Protozoa
▫️fungi

Question 9

Sterile areas of the body:

Answer 9

▫️blood, CSF
▫️Lungs
▫️stomach
▫️ uterus, Fallopian tubes, ovaries
▫️bladder and kidneys

Question 10

▫️A single-called microorganisms
▫️do not require living tissues to survive
▫️vary in size and shape
▫️divide by binary fission - can occur outside of host cells
Components: cell membrane, indiscrete nucleus, cytosol

Answer 10

Bacteria - a full living cell

can essentially duplicate

Question 11

Living requirements of bacteria

Answer 11

▫️moisture 
▫️food
▫️electrolyte balance 
▫️adequate temperature 
▫️adequate O2
▫️adequate pH
▫️adequate light

Question 12

released from cell walls of bacteria when they are lysed.

Answer 12

Endotoxins

Question 13

A unicellular organisms that do not require living tissue to survive. They vary in size, shape, and arrangement

Answer 13

Bacteria

Question 14

A bacterium has one or two types of cell walls, which differ in chemical composition.

Answer 14

Gram-positive or gram-negative

Question 15

Some bacteria secrete toxic substances, toxins, and enzymes.
Toxins consists of two types:

Answer 15

Exotoxins and endotoxins

Question 16

A latent form of bacterium with coating that is highly resistant to heat and other adverse conditions. bacteria resume a vegetative state and reproduce.

Ex. Tetanus and botulism

Answer 16

Spores

Question 17

Are produced by some bacteria and are a source of damage to the host tissues or cells. promote spread of infection

Ex: hemolysin

Answer 17

Enzymes

Question 18

A non-living intracellular parasites -requires host cells to survive

Answer 18

▫️Viruses

Question 19

Viruses consists of:

Answer 19

▫️protein coat or capsid (comes in many shapes sizes and undergoes change relatively quickly in the evolution of the virions)
▫️ genetic material (either DNA or RNA)

Question 20

A large microorganisms found throughout environment
▫️on animals, plants, humans, food
▫️unicellular ➡️ yeast
▫️multicellular ➡️ moods and mushrooms

Answer 20

Fungi

Question 21

Fungi infections are termed ?..

Answer 21

▫️mycoses or mycotic infections

Question 22

Only few fungi are pathogenic, causing infection on the skin or mucous membranes. such as:

Answer 22

▫️pneumonia
▫️thrush mouth
▫️ring worm (scalp)
▫️vaginitis (candidiasis)
▫️athletes foot

Question 23

Benefits of Fungi:

Answer 23

▫️major role in decomposition of dead matter, providing nutrients for other organisms
▫️antibiotic drugs (e.g. penicillin)
▫️food production (yogurt, bread)
▫️also keep bacteria, viruses at bay (ex.resident flora)

Question 24

Complex unicellular organisms found in water, soil ➡️ important in food chain as producers and decomposers

Transmission occurs through contaminated food or water, sexual contact,mor a vector.

Answer 24

Protozoa

Question 25

Common protozoal diseases:

Answer 25

▫️malaria
▫️traveler’s diarrhea
▫️dysentery

Question 26

Phases of Acute infection:

🔺infection is established if host’s defense s are insufficient to destroy pathogens

Answer 26

1. Exposure
2. Incubation
3. Prodrome
4. Clinical illness
5. Convalescence

Question 27

complications of infection:

Answer 27

▫️septicaemia

▫️chronic infection

Question 28

Common Laboratory and Diagnostic test to Detect infection

Answer 28

1. WBC count
2. Serum antibody levels
3. Cultures
4. Sensitivities

Question 29

elevation in WBC w/c may indicate an infectious process, often bacterial in origin

Answer 29

Leukocytosis

Question 30

decrease in WBC, which may indicate a viral infection or a problem with suppression of WBC production

Answer 30

Leukopenia

Question 31

A lab test that identifies w/c anti microbial drugs would be most effective for a specific pathogen

Answer 31

Sensitivities

Question 32

Certain factors decrease host resistance to infection

Answer 32

▫️age
▫️genetic susceptibility 
▫️immunodeficient individual
▫️severe physical and emotional stress
▫️malnutrition

Question 33

Modes of transmission of infectious Agents:

Answer 33

▫️direct contact
▫️droplet transmission
▫️airborne transmission
▫️vector transmission