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NURS 2228 - Microbiology > Midterm #1 Material > Flashcards

Midterm #1 Material Flashcards

1
Q

Define Microbiology

A

Study of microscopic agents

- 95% of microbes do NOT cause disease

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2
Q

What are the two kinds of acellular microbial agents? (non-cellular, lack cell features)

A
  1. Prions

2. Viruses

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3
Q

What is a prion?

A

Infectious proteins with no genetic material

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4
Q

What is a virus?

A

Obligate intracellular parasite (cannot replicate without a host) with either RNA or DNA as genome

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5
Q

What are the two main categories of cellular microbial agents?

A
  1. Prokaryotes

2. Eukaryotes

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6
Q

What is a defining feature of prokaryotes? What is an example?

A

They lack membrane-bound organelles.

Ex - bacteria

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7
Q

What is the defining characteristic of eukaryotes?

A

“True” cells - have typical cellular features such as nucleus, and organelles

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8
Q

What are the two different kinds of prokaryotes?

A
  1. Gram positive (stain purple) - MRSA, E-coli

2. Gram negative (stain pink)

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9
Q

What are the three different kinds of eukaryotes?

A
  1. Fungi
  2. Protozoa
  3. Other parasites (multi-cellular and typically larger
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10
Q

Are fungi single-celled or multi-celled?

A

Both!
Yeasts are single-celled
Molds are multi-celled

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11
Q

What is the defining characteristic of protozoa?

A

Unicellular

single celled organism

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12
Q

What happens when we are exposed to PrPsc?

A

PrPsc = abnormal forms (infectious) prions

- they change our normal prions to abnormal prions

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13
Q

What do abnormal prions due to the brain tissue?

A

Causes plagues or holes to form in the brain tissue

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14
Q

What is TSE?

A

Transmissible Spongiform Encephalopathy

  • prion disease
  • fatal, incurable
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15
Q

What is an example of a prion disease in sheep and in cows?

A 
Sheep = Scrapie
Cattle = Bovine Spongiform Encephalopathy (BSE) "Mad Cow Disease"
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16
Q

What are the different kinds of prion diseases in humans?

A
  1. Creutzfeldt-Jakob Disease (CJD - 2 kinds; classic and variant)
  2. Kuru Disease
  3. Fatal Familial Insomnia
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17
Q

What is the difference between classic and variant CJD?

A 
Classic = genetic predisposition to it
Variant = from eating cattle that are infected
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18
Q

What is the median duration of illness?

A

Time the patient will remain alive after diagnosis

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19
Q

What is the median age at death, median duration of illness and clinical signs and symptoms of Classic CJD?

A

Median age at death = 68
Median duration = 4-5 month
S and S = dementia, early neurologic signs

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20
Q

What is the median age at death, median duration of illness and clinical signs and symptoms of Variant CJD?

A

Median age at death = 28
Median duration = 13-14 months
S and S = Psychiatric/behavioural symptoms, painful sense of touch, delayed neurological signs

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21
Q

What does obligate intracellular parasite mean?

A

Must be inside a suitable living host cell in order to propagate - highly specific virus-host cell relationship

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22
Q

What does MERS-cov stand for?

A

Middle East Respiratory Syndrome Coronavirus

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23
Q

When was the first identified case of MERS-cov?

A

April 2012 in Saudi Arabia

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24
Q

What are signs and symptoms of MERS-cov?

A
  • fever, cough, SOB, breathing difficulties
  • pneumonia
  • gastrointestinal symptoms (diarrhea)
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25
Q

What does SARS stand for?

A

Sever Acute Respiratory Syndrome

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26
Q

What is the mode of transmission of MERS-cov and SARS?

A

Droplet (coughing/sneezing)

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27
Q

What is an incubation period?

A

Time between exposure to disease and when you show symptoms

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28
Q

What is Period of Communicability?

A

Time during which an infectious agent can be transmitted directly or indirectly from an infected person to another person

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29
Q

What is the incubation period of SARS? MERS?

A 
SARS = 2-10 days
MERS = 2-14 days
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30
Q

What is the period of communicability of SARS? MERS?

A

SARS =

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31
Q

Which has a higher fatality rate, MERS or SARS?

A

MERS (36%) compared to SARS (10.8)

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32
Q

Why will the estimated number of infected people always be a little low?

A

Because there will always be some infected people that don’t go the hospital b/c the symptoms weren’t that bad (to warrant hospitalization)

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33
Q

How is Ebola spread?

A

By direct contact with body fluids (blood) of a SYMPTOMATIC infected person (or one who has died from the disease)

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34
Q

What is the incubation period (IP) of Ebola?

A

8-10 days

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35
Q

What is the fatality rate of Ebola?

A

25-90%

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36
Q

What are some signs and symptoms for Ebola?

A

Fever, severe headache, fatigue, muscle pain, followed by diarrhea, vomiting, abdominal pain and unexplained hemorrhage

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37
Q

How can an individual help to minimize the spread of Ebola?

A
  • wash hands (soap and water)

- do NOT touch an infected person OR their body fluids

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38
Q

What are the 4 ways that Zika virus can be spread?

A
  1. Mosquito bites
  2. Sexual contact
  3. Congential transmission (infected mother to fetus)
  4. Blood transfusion and laboratory exposure
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39
Q

What happens to the body when it is infected with the Zika virus?

A

Virus attacks the brain cells, there is then not enough pressure on the developing skull - results in skull collapse (microcephaly)

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40
Q

What two types of mosquitoes spread the Zika virus? Why is it not a concern in Canada?

A
  1. Aedes aegypti
  2. Aedes albopictus
    Those species don’t live in Canada
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41
Q

When do the species of mosquitoes that carry Zika virus feed? West nile virus?

A

Zika = Daytime

West Nile = Dusk to Dawn

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42
Q

What is the name of the mosquitoes species that carries the West Nile virus?

A

Culex

- we have these in Canada!

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43
Q

What are some signs and symptoms of Zika virus?

A

Fever, rash, joint pain, conjunctivitis, muscle pain and maybe headache

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44
Q

What are the current challenges of the Zika virus (3)?

A
  • incubation period is unknown
  • when and how it is passed from mother to fetus is unknown
  • no FDA approved commercially diagnostic test
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45
Q

What are the two most common causes of healthcare associated infections?

A
  1. Gram-positive (C. diff, MRSA, VRE)

2. Gram-negative (E.coli)

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46
Q

What are the two types of fungi (eukaryotes)?

A
  1. Yeasts (unicellular)

2. Molds (multicellular)

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47
Q

What is toxoplama?

A

Single-celled eukaryotes

  • spread by contact with cats/cat litter
  • consumption of raw/undercooked meat from infected animals
  • ingestion of contaminated water
  • infected mother to fetus
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48
Q

What group/class do parasitic worms fall into?

A

Eukaryotes, multicellular

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49
Q

What are three different kinds of parasitic worms?

A
  1. Taeniasis (tapeworm)
  2. Anisakiasis (from eating raw fish)
  3. Snail/Brazilian fever - contact with contaminated water
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50
Q

What is the mode of transmission?

A

How the disease is transmitted

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51
Q

What is the portal of entry?

A

How the disease infects the new host

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52
Q

What is the portal of exit?

A

How the disease leaves the infected individual

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53
Q

What is epidemiology?

A

Study of the distribution of a disease
(or an event [what], and their determinants [how], in a given population [who] and location [where] during a defined period [when])

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54
Q

What is Dr. John Snow (Father of Epidemiology) credited with?

A

Discovered the source of cholera outbreak in London in 1854 was WATER

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55
Q

What is GIS and how does it help with epidemiology?

A

Geographic Information System

- used to help investigate outbreak and prepare for outbreak management

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56
Q

Define communicable or infectious diseases

A

Illnesses caused by an infectious agent and/or its toxin that can be transmitted directly and/or indirectly from human-human or animal-human

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57
Q

What is the only disease that we were able to eradicate worldwide through vaccination?

A

Smallpox!

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58
Q

What is the name for diseases that are transferable from animals to humans?

A

Zoonotic diseases

- rabies, avian flu, lyme disease, west nile virus

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59
Q

What are the three possible outcomes after getting exposed to a disease?

A
  1. No illness
  2. Colonization
  3. Carrier state
  4. Illness (with mild to severe s and s)
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60
Q

What does it mean if you are colonized with a disease?

A

Presence and multiplication of microbes in a host without tissue invasion/damage
- symptomatic transmission

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61
Q

What does it mean if you are in a carrier state?

A

You have the disease (but do not show signs and symptoms) and can transmit the disease AT ANY TIME
- asymptomatic transmission

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62
Q

What is the incubation period?

A

Time between exposure to an infectious agent and the appearance of first signs and symptoms

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63
Q

What is the prodromal period?

A

Early stage of signs and symptoms

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64
Q

What is the period of invasion?

A

Worsening of signs and symptoms, reaching the height of infection (possibly death)

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65
Q

What is the convalescent period?

A

Signs and symptoms diminish and disappear eventually (recovery)

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66
Q

What are the 4 clinical stages of infectious disease?

A
  1. Incubation period
  2. Prodromal period
  3. Period of invasion
  4. Convalescent period
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67
Q

When is a person contagious?

A

During the period of communicability

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68
Q

Define communicability

A

The number of people an infected person can infect in a large susceptible population [Ro]

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69
Q

What does it mean if Ro is > 1? And

A

The greater the Ro, the more contagious the disease

-

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70
Q

What is the basic reproductive number?

A

The Ro

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71
Q

Why is the Ro number important?

A
  • helps predict how fast and far a disease can spread
  • help to estimate morbidity and mortality
  • helps with resource allocation
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72
Q

What is the incidence of disease?

A

Number of NEW cases in a given time period

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73
Q

What is the prevalence of a disease?

A

All cases in a given time period (OLD + NEW cases)

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74
Q

What is the tip of the iceberg effect?

A

Many people could be infected but don’t show any signs or symptoms

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75
Q

When comparing the incidence and prevalence of HIV, why are the numbers different?

A

Prevalence is a higher number b/c people living with HIV are living LONGER (effective drug treatments)

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76
Q

What is disease surveillance?

A

Systematic approach to collect, analyze, interpret and disseminate disease data to all stakeholders in a timely fashion

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77
Q

What are the two categories for reportable diseases?

A
  1. Schedule A: reportable by ALL SOURCES (dr, RN, labs, public)
  2. Schedule B: reportable by LAB ONLY
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78
Q

What is prevalence data NOT useful for?

A

Detecting outbreaks and identifying determinants of disease

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79
Q

Define sporadic occurance

A

Randomly occurring cases of disease - not related epidemiologically

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80
Q

Define endemic

A

Cases of disease persistent in a given location in a relatively stable fashion (Lyme disease)

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81
Q

Define epidemic

A

Incidence exceeds the historical number (mean) of cases (ex. seasonal flu epidemic)

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82
Q

Define pandemic

A

World-wide or global epidemic (H1N1)

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83
Q

What are healthcare-associated infections (HAIs)?

A

Infects that occurs during or after hospitalization or stay in a health-care insitutution

  • 48 hours after hospital admission
  • up to 3 days after discharge
  • up to 30 after an operation
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84
Q

What is CA-MRSA?

What is HA-MRSA?

A 
CA = community acquired
HA = Heathcare acquired
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85
Q

What age group does CA-MRSA affect? HA-MRSA?

A 
CA = teenagers and younger adults
HA = older age groups (50+, 80+)
86
Q

What are some common types of HAIs?

A
  • UTI (catheter-associated) (30-40%)
  • Lower respiratory tract infections (10-20%)
  • Surgical site infections (15-25%)
  • Blood (central line-associated blood stream infections) (5-15%)
87
Q

What is cystitis?

What drug is used?

A

A bladder infection

- Nitrofurantoin (resistance is uncommon)

88
Q

What is pyeleonephritis?

What drug is used?

A

Kidney infection

- IV ceftriaxone

89
Q

What are carbapenems?

A

ESBLs

(extended spectrum beta lactamases

90
Q

What is an SSI?

A

Surgical site infection

91
Q

What are the classifications of SSIs?

A
  1. Incisional
    - Superficial
    - Deep
  2. Organ/space
92
Q

What does a superficial surgical site infection involve?

A

Involves only skin and subcutaneous tissue

93
Q

What does a deep surgical site infection involve?

A

Involves deep soft tissues (fascia and muscle)

94
Q

What does an organ/space surgical site infection involve?

A

Involves any part of anatomy other than incision opened or manipulated

95
Q

What is septicemia?

A

Bloodstream infections

96
Q

What is primary septicemia?

A

Direct introduction of microbes into blood (from patient themselves, HCWs, or through central lines)

97
Q

What is secondary septicemia?

A

The spread of microbes from a pre-existing distant infection

98
Q

What are the clinical signs and symptoms of SSIs (surgical site infections)?

A
  • Febrile
  • Redness (Erythema)
  • Swelling
  • Warm
  • Tender/pain
  • Drainage?
99
Q

Approximately how many patients will acquire an HAI?

A

5-10%
= > 200,000 cases per year
= > 8,000 deaths per year

100
Q

What are the direct costs of HAIs?

A

Associated with providing care to patients (estimated to be $1 billion

101
Q

What are the indirect costs of HAIs?

A
  • Loss of productivity (someone calls in sick)
  • Loss of business income
  • Lawsuits (medical malpractice)
102
Q

Which disease had the biggest economic impact of HAIs?

A

SARS

- $30-50 billion USD

103
Q

What is an agent?

A

The cause of an infectious disease (microbial toxins, bacteria, viruses, fungi, protozoa, parasites, prions)

104
Q

What is a host?

A

A living organism that harbours an infectious agent

105
Q

What is the definition of environment (pertaining to the epidemiological triangle)?

A

Settings external to the host that allows for transmission of the agent

106
Q

Why can an agent survive in a host?

A

Because the host allows for the sustained survival of the infectious agent that resides in/on its body UNDER NATURAL CONDITIONS (not produced in a lab)

107
Q

True or false:

The infectious agent may or may not produce a disease in the host but is provided opportunities for transmission

108
Q

What are the three types of relationships that humans can have with microbes?

A
  1. Mutualistic
  2. Commensal
  3. Parasitic
109
Q

What is a mutualistic relationship?

A

Benefits both parties

110
Q

What is a commensal relationship?

A

No harm but not benefit either

111
Q

What is a parasitic relationship?

A

Infectious agent benefits; host is harmed

112
Q

What are normal microbiota?

A

Agents that permanently live in the human body

113
Q

What are transient microbiota?

A

Agents that may inhabit and reproduce in a host briefy, but the hosts natural defenses do not allow them to become permanent

114
Q

What are some of the benefits of normal microbiota?

A
  • aid in development and maturation of host immune system

- protect host from pathogens (via competition or production of antimicrobial substances)

115
Q

What is the potential harm of normal microbiota?

A

If the host becomes immunocompromised, they could become opportunistic pathogens

116
Q

What is an opportunistic pathogen?

A

Pathogens that take advantage of a weaker host (in normal conditions they would not cause problems)

117
Q

What is an obligate pathogen?

A

Agents that always cause disease/damage in the host in order to be transmitted

118
Q

What is a primary immunodeficiency?

A

Person is born with a genetic defect in the immune system (genetic susceptibility)

119
Q

What is a secondary immunodeficiency?

A

An acquired susceptibility (AIDS & TB)

120
Q

What are 3 examples of medical conditions that cause secondary immunodeficiencies?

A

Cancer, cystic fibrosis, co-morbidities (diabetes and obesity)

121
Q

What are 3 examples of medical therapies that cause secondary immunodeficiencies?

A
  1. Anti-inflammatory agents
  2. Anti-rejection drugs (transplant patients)
  3. Oncology interventions (radiation and chemotherapy)
122
Q

What are some examples of factors that affect the host’s immune system (making them more susceptible to acquired immunodeficiencies)? Why?

A
  1. Chronic stress
  2. Lifestyle habits (alcohol, smoking, drugs)
  3. Age
  4. Sex (differences in anatomy, hormones, pregnancy, etc)
123
Q

Why do chronic stress, lifestyle habits, age, sex, and malnutirion affect the host’s susceptibility to acquired immunodeficiencies?

A

Impairs the amount and/or functions of cells and chemical messengers associated with inflammatory and immune responses

124
Q

Why is breastfeeding good for a child? What happens to the antibodies that the mother give to the child?

A

Mother shares antibodies in utero with the fetus.
Neonates receive some protection from breastfeeding
- but it doesn’t last forever (they are MOM’s antibodies, not the CHILD’s, so the child will actually attack them - they are foreign bodies)

125
Q

Why does the mother not reject her baby as a foreign thing?

A

Mother’s are immunosuppressed (to a degree)

126
Q

What are MORE factors that influence a host’s risk of infection?

A
  • socioeconomic status
  • occupational exposure
  • travel history
  • person hygiene
  • vaccination
  • exercise/physical activity
  • risk activities (needle sharing)
127
Q

What are MORE factors that influence a host’s risk of a HAIs?

A
  • invasive dwelling devices
  • lengthy instrumentation and/or surgery
  • long stay in healthcare facility
  • prior and prolonged use of antimicrobials
  • presence of existing wounds
128
Q

What are 6 different kinds of agents?

A
  1. Bacteria
  2. Viruses
  3. Protozoa
  4. Fungi
  5. Parasite and prions
  6. Microbial toxins
129
Q

Define communicability

A

Ease of transmission of the agent

130
Q

What are 3 agent factors that influence the risk of infection?

A
  1. Communicability
  2. Survivability
  3. Adaptability
131
Q

What is the formula for communicability?

A

Ro = C * P * D

C = number of contacts
P = probability of transmission per contact
D = Duration of infectiousness (POC)
132
Q

Define the infectious dose (ID)

A

Minimum number/dose of agents required to cause an infection

- infection will occur if exposure exceeds infective dose

133
Q

Define survivability

A

How well an agent survives on a surface

134
Q

What happens if a person comes into contact with a disease that is over the clinical infection threshold?

A

Person will acquire the disease

135
Q

What happens if a person comes into contact with a disease that is over the subclinical infection threshold?

A

Exposure level still exceeds infective dose; person will have mild or no s/s

136
Q

Which agents have the highest survivability? The lowest?

A 
Highest/best = prions
Lowest/worst = viruses with lipid envelopes
137
Q

What is the virulence factor?

A

Intrinsic characteristics of an agent that enable them to cause tissue damage/disease

138
Q

What are 2 pieces of the virulence factor?

A
  1. Ability to evade and/or subvert the host’s defenses

2. Survival in the host (longer period of communicability = greater chance of transmission)

139
Q

How does an agent adapt to or in the host’s environment?

A
  1. Mutation

2. Genetic exchange

140
Q

Define direct transmission

A

Transmission from infected host to another

141
Q

Define indirect transmission with intermediate hosts and adaptation

A

Agent may adapt and become more efficient

- adapt to different host species

142
Q

What is reassortment?

A

A mutant strain of the agent

  • avian flu and the human flu strains mix with a mutation
  • we ALL lack immunity!
  • if it has aspects of the human flu strain, it will be more successful at human-human transmission
143
Q

What are factors that affect the virulence of an agent?

A
  1. Adherence/attachment
  2. Toxigenicity
  3. Invasiveness
  4. Evasion/subversion of host defenses
  5. Immunopathology
144
Q

Define toxigenicity

A

Ability to produce toxins

- endotoxins or enterotoxins

145
Q

Define immunopathology

A

Sometimes the immune response is too strong and causes damage to the host from itself

146
Q

What is a micro-environment?

A

Where the agent is located

147
Q

What is the macro-environment?

A

Where the host is located

148
Q

What are 5 micro-environmental factors that influence how well an agent survives, grows and transmits?

A
  1. Oxygen
  2. Water
  3. Temperature
  4. pH
  5. Nutrients
149
Q

What is an obligate aerobe?

A

Needs oxygen

  • will die without it
  • neutralizes toxic forms of oxygen
150
Q

What is an example of an obligate aerobe?

A

Mycobacterium

151
Q

What is a facultative anaerobe?

A

Increased growth in the presence of oxygen

- both aerobic and anaerobic

152
Q

What is an example of a facultative anaerobe?

A
  • Streptococcus
  • Staphylococcus
  • Enterobacericeae
  • MRSA
  • VRE
153
Q

What is an obligate anaerobe?

A

Can only survive is oxygen is absent

- will die in the presence of O2

154
Q

What is an example of an obligate anaerobe?

A

Clostridum

155
Q

What is an aerotolerant anerobe?

A

Does not care if oxygen is present or not

- does NOT use O2

156
Q

What is an example of an aerotolerant anaerobe?

A

Lactobacillus

157
Q

What is a microaerophil?

A

Requires low concentrations of oxygen for growth

158
Q

What is an example of a microaerophile?

A

Neisseria gonorrhoeae

159
Q

What are capnophiles?

A

Agents that prefer high concentrations of CO2

160
Q

What temperatures do psychrophiles prefer?

A

Cooler temperatures - freezing will not kill them, only slow their growth

161
Q

What temperatures do thermophiles prefer?

A

Extremely high temperatures

162
Q

What temperatures do mesophiles prefer?

A

30-40 degrees C

= HUMAN BODY temperatures!

163
Q

If a container of food in the fridge contained Clostridium Botulinum, where in the container would they be found?

A

AT THE BOTTOM
- obligate anerobic
(further away from oxygen source)

164
Q

True or False:

The optimum pH range for an agent is high

A

False:

The optimum pH range for an agent is quite narrow

165
Q

What pH range are infectious agents typically? What are they called?

A

pH 5.5-8

Neutrophiles

166
Q

What is the name for agents that prefer acidic environments?

A

Acidophiles

167
Q

What is the name for agents that prefer basic environments?

A

Alkalophiles

168
Q

Do fungi or bacteria prefer a more acidic environment?

A

Fungi prefer a more acidic environment

169
Q

What does a low Aw value mean?

A

The agent can survive WITHOUT a lot of water

170
Q

What is the water activity level (Aw)?

A

Amount of water available in a micro-environment (such as food)

171
Q

What can you add to food to lower the Aw value?

A

Salt or sugar

Dry it!

172
Q

What happens to bacteria in a hypertonic environment?

A

Water will leak out of the bacteria and into the solution (to try to dilute it)
- plasmolysis

173
Q

What are the 6 essential nutrients?

A 
Carbon
Nitrogen
Hydrogen
Sulfur
Phosphate
Minerals
174
Q

Define heterotroph

A

Organism that needs to eat or absorb their energy source

175
Q

Define chemoheterotroph

A

Organism that uses the metabolic conversion of the nutrients from other organisms for energy

176
Q

Define autotroph

A

Organism that makes it’s own food

  • Photoautotroph
  • Chemoautotroph
177
Q

What are some macro-environmental factors that influence infectious disease transmission?

A
  • poor sanitation
  • overcrowding
  • construction activities
  • contaminated air
178
Q

How can staffing affect infectious disease transmission?

A
  • inadequate staffing
  • inexperienced staff
  • indifferent attitude
  • knowledge deficit
  • failure to identify cases
179
Q

What are the 6 steps in the chain of transmission?

A
  1. Infectious agent
  2. Reservoir
  3. Portal of exit
  4. Mode of transmission
  5. Portal of entry
  6. Susceptible host
180
Q

What is a microbial reservoir?

A

A living or non-living object that permits sustained survival and transmission of an infectious agent

181
Q

How is a secondary reservoir different from a primary reservoir?

A

Secondary doesn’t support replication

182
Q

What are the three types of carriers?

A
  1. Incubatory
  2. Convalescent
  3. Healthy
183
Q

What does it mean if the source of infection is endogenous?

A

Patient themselves (self-infection) is the source of infection

184
Q

What does it mean if the source of infection is exogenous?

A

Living reservoirs: (OTHER patients), health care workers or Non-living reservoirs: air, water, food, catheter, IV fluids, ventilators

185
Q

What are the two main modes of transmission?

A
  1. Direct (transmitted by direct contact between reservoir and host)
  2. Indirect (transmitted to host via intervening agent)
186
Q

What are the 5 categories of modes of transmission?

A
  1. Air-borne
  2. Droplet spread
  3. Direct contact
  4. Indirect contact
  5. Common vehicle
187
Q

What is vertical transmission?

A

Transmission from mom to baby

  • trans-placental
  • intrauterine transmission
  • infected birth canal
188
Q

What is horizontal transmission?

A

Transmission from person to person

189
Q

What are examples of viral diseases that are transmitted through direct implantation or biting?

A 
Rabies
Bloodborne virses (hepatitis B and B, HIV)
190
Q

What are example of bacterial diseases that are transmitted through direct implantation or biting?

A 
Tetanus (Clostridium tetani)
Capnocytophaga canimorsus (found in dog's mouths)
191
Q

What are examples of diseases that are spread through direct droplet transmission?

A
  • SARS
  • Influenza
  • Measles
  • Mumps
  • Rubella
  • Common cold
  • Meningitis
192
Q

How is airborne transmission different than droplet transmission?

A

Airborne = smaller droplets (1-5 micro meters in diameter)

  • can stay suspended in air indefinitely
  • agents remain viable and infectious for an extensive period of time
193
Q

What is an example of a disease that is an airborne transmissions?

A
  • TB (mycobacterium tuberculosis)

- Legionnaire’s disease

194
Q

What is a vector?

A

Living organisms that transmit an infectious agent to a host

195
Q

Vectors are normally, what kind of living thing?

A

Arthropods (mosquitoes, ticks)

196
Q

What are the two kinds of vectors?

A
  1. Biological

2. Mechanical

197
Q

What is a biological vector?

A

An organism which not only transports a pathogen, but also plays a role in the life cycle of the pathogen

198
Q

What is a mechanical vector?

A

An organism which ONLY transports a pathogen

199
Q

True or False:

Biological vectors are reservoirs and hence can be considered a mode of direct transmission

A

TRUE!

- because they can survive, live, and multiply in a BIOLOGICAL vector

200
Q

True or False:

Non-living objects do not act as an intermediary for indirect transmission

A

FALSE!

Non-living object DO act as an intermediary for indirect transmission

201
Q

What is a common vehicle?

A

Infects multiple hosts (ex. food and water during an outbreak)

202
Q

What is a fomite?

A

Non-living objects that can act as intermediaries for indirect transmission

203
Q

What does the route of transmission often refer to?

A

Portal of entry (ingestion route) but sometimes can include both portals of entry AND EXIT (fecal-oral route)

204
Q

What are the portals of exit and entry?

A

Body parts/substances through which infectious agents leave and enter the body respectively

205
Q

What are some common portals of entry?

A
  • mucous membrane
  • conjunctiva
  • respiratory tract
  • gastrointestinal tract
  • genitourinary tract
  • skin
206
Q

What is the parenteral route?

A

Through punctures, injections, bites, cuts, wounds, and surgical incisions

207
Q

What does IPCT stand for?

A

Infection Prevention and Control Team

208
Q

What are the roles and responsibilities of IPCT?

A

To develop, implement, and monitor the effectiveness of IPC policies and procedures by:

  • establishing guidelines
  • providing advice
  • auditing
209
Q

What is the main objective in contact tracing?

A

To identify those who have come into direct contact with person(s) who have a highly contagious and/or dead infectious disease

  • to prevent further spread of the infection
  • to provide required interventions
210
Q

What is mupirocin (Bactroban)

A

Antibiotic used for intranasal decolonization

211
Q

What is cholorhexidine gluconate?

A

Antiseptic for bathing patients

212
Q

What is photo-disinfection?

A

Use non-thermal light energy to decolonize nasal carriage

NURS 2228 - Microbiology (9 decks)

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