E1 Ch 6 Infection

Question 1

microbiology

Answer 1

the study of microorganisms, very small living forms that are visible only with a microscope

Question 2

microorganisms

Answer 2

include bacteria, fungi, protozoa, viruses
can be:
nonpathogenic
-usually do not cause disease unless conditions change
-part of normal flora
- often beneficial
or
pathogenic
-disease-causing microbes

Question 3

bacteria

Answer 3

• no nuclear membrane or nucleus
• function metabolically and reproduce
• cell wall
• do not require living tissues to survive
• can be gram+ or gram-
• flagellae or pili used for mobility or attachment
• may secrete toxins or enzymes that damage tissues or antibiotics
• some form spores, which are highly resistant to heat and disinfectants, and can remain dormant for long periods of time
• reproduces with binary fission
• treated with antibiotics

Question 4

virus

Answer 4

• mutates quickly
• often use vaccines to protect against them
• DNA and RNA
• hijacks human cells to manufacture viral DNA/RNA, lysis of cell allows spread of virus
• can become latent then active later (ex shingles)
• can only live short period on surface
• treated with antivirals

Question 5

protozoa

Answer 5

• may live independently
• lacks cell wall
  -treated with antiprotozoals/antimalarials
  ex: trichomoniasis (trichomonas vaginalis is an STI), malaria (plasmodium found in RBCs, spread by mosquitos)

Question 6

fungi

Answer 6

• rarely pathogenic
• treated with antifungals
• generally topical, though can be symptomatic
• hyphae under microscope
  ex: tinea (tinea pedis: athletes foot, tinea corporis: ringworm, tinea cruris: jock itch), candida (thrush and vaginitis, opportunistic infection), pneumocystis jirovecii (opportunistic organism causing pneumonia, commonly seen with AIDs), histoplasma (can cause neuro disease and can be transmitted to fetus)

Question 7

helminths

Answer 7

• parasites
• treated with antiparasitics
• enter body through skin, ingestion, inhalation
• infections more common in young children

Question 8

normal flora

Answer 8

normal flora live on your skin and protect you from pathogenic infections taking over; found in/on skin, mucous membranes, GI, etc.

Question 9

resident flora present

Answer 9

skin, nose, pharynx, mouth, colon, rectum, vagina

Question 10

sterile area

Answer 10

blood, cerebrospinal fluid, lungs, uterus, fallopian tubes, ovary, bladder, kidney

Question 11

sporadic transmission

Answer 11

in a single individual

Question 12

endemic transmission

Answer 12

continuous transmission within a population

Question 13

epidemic

Answer 13

higher than normal transmission or spread to new geographical area

Question 14

pandemic

Answer 14

transmission has occurred on most continents

Question 15

chain of infection

Answer 15

Question 16

how to prevent infection

Answer 16

PPE, hand washing, covering coughs, rabies vaccines for dogs, avoid sick people, protect immune system, cleaning surfaces, eliminate vectors, mask when sick, treat pathogens

Question 17

1 way to prevent infection

Answer 17

hand hygiene

Question 18

factors that decrease host resistance

Answer 18

age (infancy and older adults), pregnancy, genetic susceptibility, immunodeficiency, malnutrition, chronic disease, severe physical or emotional stress, inflammation or trauma, impaired inflammatory response

Question 19

pathogenicity

Answer 19

capability of a microbe to cause disease

Question 20

virulence

Answer 20

disease producing power, degree of pathogenicity

Question 21

nosocomial

Answer 21

occurs in hospitals, spread by healthcare workers, increased risk with depressed immune system
prevent with proper hand hygiene, clear contaminated objects, clean surfaces

Question 22

standard/universal precautions

Answer 22

PPE to avoid bodily fluid (gloves, goggles, etc.)
others used in addition (airborne, droplet, contact, etc.)

Question 23

local signs of infection

Answer 23

pain, swelling, redness, warmth, purulent exudate (pus) if bacterial, serous clear exudate if viral

Question 24

systemic signs of infection

Answer 24

fever may be present, fatigue and weakness, headache/nausea

Question 25

methods of diagnosis

Answer 25

culture and staining techniques (used to identify causative agent, drug sensitivity tests)
blood tests
- variation in the number of leukocytes (leukocytosis: bacterial infection, leukopenia: viral infection)
- differential count
- c-reactive protein
- erythrocyte sedimentation rate

Question 26

incubation period

Answer 26

body is exposed, asymptomatic

Question 27

prodromal period

Answer 27

nonspecific symptoms

Question 28

acute period

Answer 28

infectious disease develops fully