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Flashcards in Chapter 11 Deck (197)
1

Microorganisms that are normally present in and on the
body are called ____>

normal microbiota

2

Biological survival advantage to the
microbe to live in a host
that can provide both nutrients and _____.

protection

3

The host benefits as _____ can help to exclude
potential
pathogens

microbiota

4

Some microbiota can even improve _______ to the host.

improve
i.e. E. coli in the intestines can produce vitamin K

5

______ we have a peaceful coexistence with out microbiota.

normally

6

Out microbiota outnumber our human cells ____ or there are ___ more bacterial cells than human cells.

10:1
10x

7

Sites with Microbiota

Skin and its adjacent mucous membranes
respiratory tract
gi tract (various parts)
outer opening of urethra
external genitalia
vagina
external ear canal
external eye (lids, conjunctiva)

8

Most areas of the body in contact with the outside environment harbor _____.

resident microorganisms

9

Sites that have no contact with the external environment (directly or indirectly) should be _____ - internal tissues adn organs along with their fluids (CSF, blood, muscles, etc. )do not harbor normal microbiota.

sterile

10

Each site of _______ has a relatively constant
population, although it can alter a bit over time and as we
move environments

resident microbes

11

_____ are typically passing through

transient microbes

12

_____ are normal microbiota that can sometimes cause opportunistic infections.

opportunistic microbes

13

Opportunistic microbes can occur in hosts with ____ or suppressed immune systems.

weakened host defenses

14

Opportunistic microbes can occur when host defenses are ____ such as during surgery.

breached

15

Uterus and
contents normally
_____ during embryonic
and
fetal development

sterile

16

Passing through the birth canal exposes the baby to the
mother’s
vaginal ____. This begins the colonization
process.

biota

17

C-section babies are exposed via adult
____
biota when
they are held

skin

18

Microbiota colonization ______ as the baby interacts
with the environment and even breathes.

continues

19

Within ____ hours after delivery, a vaginally
delivered
baby has been colonized by
Streptococci, Staphylococci,
and Lactobacilli

8 - 12 hours

20

______ babies start with a mixed population of coliforms, Lactobacilli, Strep & Staph

formula fed

21

_____ babies tend to start with Bifidobacterium whose growth is favored by a growth factor in breast milk. The organisms colonies milk duct and passes to baby.

breast fed

22

________ continues as the infant comes into contact with family members, health care personnel, the environment.

colonization

23

By the time babies ____ or ____ anything other than formula or breast milk, their normal microbiota is about the same.

eat or drink

24

______ have the potential to cause disease in every individual (healthy and immunocompromised)

true pathogens

25

_____ cause disease in immunocompromised hosts and not typically healthy individuals (unless their immune systems are breached or they are temporarily immunocompromised)

opportunistic pathogens

26

_____ is a microbe that can cause disease is a susceptible individual.

pathogen

27

_______ is an organism's potential to cause infection or disease. The more pathogenic an organism, the more severe its disease process is.

pathogenicity

28

______ is any characteristic or structure of the microbe that contributes to its virulence

virulence factor

29

The majority of pathogens are adapted to a specific portal of _____.

entry

30

For many pathogens, if they enter the ____ portal, they will not be infectious.

wrong
i.e. influenza causes disease via entrance tot eh nasal mucosa but will not cause a skin infection

31

Occasionally, ______ portal can be used for entry.

more than one
i.e. Mycobacterium tuberculosis can enter through both the respiratory and gastrointestinal tracts to cause disease

32

The _____ is a portal of entry via nicks, abrasions, punctures, mucous membranes of the lips, burrow through the skin, via insect bites, and conjunctiva of the eye.

skin
i.e. Staph bolis
Tetanus
Herpes simplex 1

33

The _____ is a portal of entry by eating/drinking contaminated foods and fluids via fomites.

GI tract
i.e. Salmonella
E. coli

34

The ____ is a portal of entry via inhalation of offending organism.

Respiratory tract
i.e. influenza
measles

35

The ______ is a portal of entery through the skin/mucosa of penis, external genitalia, vagina/cervix, urethra; may enter through an unbroken surface or through a cut or abrasion.

Urogenital tract
i.e. HIV
HSV-2

36

Some microbes can cross the ____ and harm the fetus.

placenta
i.e. Treponema causing Syphilis

37

Other infections occur perinatally, when the child is contaminated by pathogen in the _____.

birth canal
i.e. Herpes

38

_____ infections is an acronym for a group of diseases that cause congenital (present at birth) infections.

TORCH

39

What does TORCH stand for?

Toxoplasmosis, "other", rubella, cytomegalovirus, and herpes simples

40

_____ is the minimum number of microbe needed to cause disease (for an average individual)

infectious dose (ID)

41

ID50 is the number of microbes needed to cause infection in ___ of a population.

50%

42

For most individuals, infection only proceeds if the proper infectious ____ is present.

dose

43

Microorganisms with smaller IDs have greater ______. Only a few microbes needed to cause disease.

virulence

44

ID for tuberculosis about ___ cells.

10

45

ID for gonorrhea is ____ cells.

1000

46

ID for cholera is _____ cells

1,000,000,000

47

Adhesion to the host is dependent on binding between specific molecules on both the host and _____. Often this is proteins on the surface of the pathogen binding to host cell receptors.

pathogen

48

A pathogen is limited to only those cells (and organisms) to which it can successfully bind. Colonization depends on ____.

interaction

49

Firm attachment is almost always a prerequisite for causing ____ since the body has so many mechanisms for flushing microbes from tissues.

disease

50

Occasionally microbes can cause disease via toxins without ____.

colonization

51

An example of an adhesion is ______ fimbriae attach to genital epithelium.

Neisseria gonorrhoeae

52

An example of adhesion is Strep pyogenes adheres via its _____.

sticky capsule

53

An example of adhesion is Influenza binds via its spikes binding to ______.

host cell receptors

54

An example of adhesion is when parasitic worms use suckers, hooks, and ____ to attach to host tissues.

barbs

55

______ are white blood cells that engulf and destroy foreign materials and pathogens. These are part of your immune system. (3rd step - surviving host defenses)

Phagocytes

56

______ are secreted by some pathogens to avoid pahgocyte attack. (3rd step - surviving host defenses)

antiphagocytic factors

57

An example of surviving host defenses is when ____ are toxic to white blood cells. Produced by Streptococcus and Stp\aphylococcus species.

Leukocidins

58

______ makes it difficult for the phagocyte to engulf the pathogen, for example Neisseria species.

Capsule (3rd step - surviving host defenses)

59

Some pathogens can _____ after ingestion (bypassing their killing mechanisms).

survive inside phagocytes
i.e. mycobacterium
(3rd step - surviving host defenses)

60

Three main ways that microorganisms cause damage to their hosts.

1.directly through the action of enzymes which damage host cells and tissues
2.directly through the action of toxins which cause damage to host cells and tissues
3. indirectly by inducing the host’s defenses to
respond excessively or
inappropriately, resulting in the host’s immune system causing damage or even shock and
death.

61

Extracellular enzymes, ____, are secreted enzymes that break down and damage tissues or dissolve the host's defense barriers.

exoenzymes

62

_____ degrade mucus making it easier for pathogens to access mucus lined tissues.

Mucinase

63

_____ degrade keratin making it easier for pathogens to colonize and remain in keratin rich tissues (like skin)

keratinase

64

_____ degrade collagen. Collagen found in connective tissues in the body.

collagenase

65

_____ degrade hyaluronic acid. Hyaluronic acid found between cells in the body.

Hyaluronidase

66

_____ are a potent source of cellular damage.

bacterial toxins

67

____ is a specific chemical product that is poisonous to other organsisms.

toxin

68

Toxins are named according to their ___.

target.

69

____ act on the nervous system.

neruotoxins

70

____ act on the intestines.

enterotoxins

71

_____ lyse red blood cells

hemotoxins

72

____ damage the kidneys

nephrotoxins

73

Characteristics of bacterial toxins

toxicity
effects on teh body
chemical composition
immune response
fever stimulation
manner of release
typical sources

74

_______ are proteins secreted by some bacterial species. Exotoxins have a strong specificity for a target cell and extremely powerful, sometimes deadly effects.

exotoxins

75

_____ are lipopolysaccharide (LPS), part of the outer membrane of the gram-negative cell walls

endotoxin

76

Exotoxins toxicity is toxic in ____.

minute amounts

77

Exotoxins effects on the body are specific to a ____.

cell type (liver, blood nerve)

78

Exotoxins chemical composition is made of ____.

small proteins

79

Exotoxins immune response ____.

stimulates antitoxins

80

Exotoxins _____stimulate fever

usually doesn't

81

Exotoxins manners of release is ____.

secretion from a live cell

82

Exotoxins typical sources are _____.

a few gram positive and gram negative

83

_____ is a bacterial species that can produce endospores and a potent exotoxin.

C. tetani
(Clostridium tetani)

84

Disease occurs most often when wounds become _______ with C. tetani endospores from the environment.

contaminated

85

Once in the host, a nice warm environment, the endospores germinate (bacterial cells grow) and the growing cells begin to ____ that migrates through the host body.

produces toxins

86

Endotoxin toxicity occurs in ____.

high doses

87

Endotoxin effects the body via ______.

system: fever, inflammation

88

Endotoxin chemical composition is a ____.

lipopolysaccharie of cell wall

89

Endoxtoxin immune response ___ stimulate antitoxins.

does not

90

Endotoxin _____.

stimulates fever

91

Endotoxins maner of release is by the ____.

cell via shedding or during lysis

92

Endotoxins typical sources are ____.

gram negative bacteri

93

____ disease progression begins with the toxin migration along neural paths from the wound to site to the CNS. Once at teh CNS, the toxin affects the _______. Disease results in progressive rigidity and violent spasms of the torso and limb muscles. Pharyngeal muscles affected and death typically results in respiratory failure.

tetanus
neuromuscular junctions

94

C. botulinum produces ____, one of the most lethal toxins known.

botulinum toxin

95

C. botulinum is commonly found in ___ in the form of endospores.

soil

96

When the endospores find a hospitable environment they will germinate into growing cells and begin producing endotoxin with ______.

C. botulinum

97

with C. botulinum happens occasionally happens in the canning process with ____ cans that indicate that something is growing inside producing gases which expand the can.

puffed out cans

98

____ disease is most often an intoxication and not a bacterial infection. In these cases people ingest the toxin which alone can cause disease without the ingestion or colonization of bacterial cells.

botulism

99

When ____ botulism can happen when a baby ingest C. botulinum that colonizes and produces toxin inside the body.

infant

100

Infant botulism can happen from ___ contaminated with soil containing endospores. This is why babies under ___ should not be given honey.

honey
under 1 years old

101

Botulism disease process begins with ingestion and the toxin is absorbed by the upper GI tract and passes into the blood stream. The exotoxin moves to the peripheral neuromuscular synapses and blocks the release of the neurotransmitter _____. This results in paralysis.

acetycholine

102

Wounds can also become contaminated with ____, resulting in a wound botulism.

endospores

103

Treatment for botulism, if caught early, you can use an ___ that blocks the action of neurotoxin circulating in the blood.

antitoxin

104

The mortatiity rate for untreated botulism is ___.

50%

105

C. diptheriae causes ____, a toxin mediated disease.

diptheria

106

Fatality rate for diphtheria is ____ (higher in the persons younger than 5 and older than 40)

5-10%

107

Transmission of ____ occurs from direct respiratory or physical contact with patient or carrier.

C. diptheriae

108

In areas where diptheria is endemic, C. diphtheriae in as _______ nasopharyngeal flora is common.

normal

109

C. diptheriae is gram _______ that does not produce endospores.

gram positive

110

Diphtheria disease is characterized by sore throat, fever, and the formation of ______ on the tonsils, pharynx, and/or nasal cavity.

a membranous coating

111

The membranous coating caused by Diphtheria is thick and strong fibrous coating that can result in ____.

suffocation

112

Diptheria toxin causes ____ of host cells and tissues.

death (necrosis)

113

A form of diptheria can affect the skin causing _____.

tissue necrosis

114

_____ are any objective evidence of disease as noted by an observer.

sign
i.e bacteria in a blood sample

115

____ are subjective evidence of disease as sensed by the patient.

symptom
i.e. headach or feeling bad

116

______ when a disease can be identified or defined by a certain complex of signs and symptoms.

syndrome

117

When microbes enter the body, remain confined to a specific tissue is called _____.

localized infection
i.e. boils, warts,

118

An infection spreads to several sites and tissue fluids (usual via the bloodstream), but may travel by other means such as nerves (rabies) and cerebrospinal fluid (meningitis) is called _____.

systemic infection
i.e. mumps, rubella, aids, chickenpox

119

Infectious agent spreads from a local site and is carried to other tissues is called a ____.

focal point
i.e. tb, pharyngitis

120

Several agents establish themselves simultaneously at the infection site is called ___.

mixed infection or polymicrobial infection i.e. human bite infections, wound infections, gas, gangrene

121

The initial infection is called the ___.

primary infection
i.e. can be any infection

122

A second infection caused by a different microbe, which complicates a primary infection; often a result of lowered host immune defenses is called a ____.

secondary ifnection
influenza, complicated by pneumonia

123

Infection comes on rapidly with sever but short lived effects is called a ____.

an acute infection
influenz

124

Infection that progresses and persists over a long period of time is called ____.

chronic infection
i.e. HIV

125

Signs of infection in the blood.

leukocytosis
leukopenia
septicemia
bacteremia or viremia

126

_____ is a sign of blood infection that increases the level of white blood cells.

leukocytosis

127

____ is a sign of infection, when white blood cells decrease.

leukopenia

128

______ is a general state in which microorganisms are multiplying int he blood and are present in large numbers when there is an infection in the blood.

septicemia

129

____ or viremia is a bacteria or viruses that are present in the blood but not multiplying.

bactermia

130

Stage of infection

1. finding a portal of entry
2. attaching firmly
3. surviving host defenses
4. causing damage (disease)
5. exiting host

131

_____ is the primary habitat in the natural world from which a pathogen can be found living.

reservoir

132

_____ include any area that is not living (not a live host). These tend to be environmental such as soil and water for examples.

non-living reservoirs

133

____ are the host in which this organism can be found consistently including animals, insects, humans for example.

living reservoirs

134

A ____ carrier is an individual who carries a pathogen without disease symptoms and is capable of spreading it to others.

human

135

Recovery of the host does not always mean the microbe has been removed or destroyed by ___.

host defenses

136

____ is a dormant state of microbes in certain chronic infectious diseases.

latency

137

_____ occurs with herpes simples, herpes zoster, hepatitis, HIV

viral latency

138

_____ occurs with syphilis, thyphoid fever, tuberculosis.

bacterial latnecy

139

Progression of Infection

1. incubation period
2. prodromal
3. invasion
4. convalescensce

140

____ period is the time from initial contact with the infectious agent (at the portal of entry) to the appearance of the first symptoms. This can last from 2 to 30 days.

incubation

141

_____ period is when the earliest notable symptoms of most infections appear as a vague feeling of discomfort. This short period lasts 1-2 days.

prodromal

142

_____ period occurs when the infectious agent enters, during which it multiplies at high levels, exhibits it greatest virulence, and becomes well established in its target tissues. This period if often marked by fever and other prominent and more specific signs and symptoms, which can include cause, rashes, severe pain, etc. The length of the this period is extremely variable.

invasion

143

As the patient begins to respond to the infection, the symptoms decline sometimes dramatically, other times slowly. During the recovery that follows, called the ______, the patient's strength and health gradually return owing to the healing nature of the immune response. During this period, many patients stop taking their antibiotics, even though there are still pathogens in their system. The bacteria that are left to repopulate are the ones with the higher resistance.

convalescent period

144

Review stages of infection and disease graph p 303

.

145

____ is a living organism that transmits an infectious agent from one host to another

vector

146

The majority of vectors are biting arthropods like ____ and ____.

ticks and mosquitoes

147

_____ is an infection indigenous to animals but naturally transmissble to humans.

zoonosis

148

Rabies, Anthrax, and salmonella are types of ____.

zoonosis

149

Rabies is passed from mammals to ____.

humans

150

Anthrax is passed from ______ to humans.

liverstock/cattle

151

Salmonella is passed from _____, ____, reptiles, rodents to humans.

mammals, birds

152

____ participates in a pathogen's life cycle in some way.

biological vectors
i.e. plasmodium species causing malaria need the human host and mosquito to complete a life cycle

153

_____ transport the infectious agent without being infected.

mechanical vectors
i.e. a fly landing on dog feces in one yard and landing on food at a picnic in another yard

154

_____ is when an infected host can transmit to another host and establish infection in that host.

communicable disease

155

______ does not arise through transmission of the infectious agent from host to host.

non-communicable disease
i.e. invaded by his or her own microbiota

156

_____ shelter a pathogen, spreads it to others without any notice, and who may not have experienced disease.

carrier

157

Direct transmission of communicable infectious diseases

1. contact - sex, kiss
2. droplets - cold, chickenpox
3. vertical - HIV, syphilis
4. biological vector - west nile, malaria

158

Indirect transmission of communicable infectious diseases

1. fomites - S. aureus
2. food, water, biological products - E. coli, salmonella
3. Air - tb

159

____ or ____ diseases are disease must be reported to authorities. Still other disease are reported on a voluntary basis.

reportable or notifiable diseases

160

Review reportable diseases pg 315

.

161

_____ deals with the incidence, distribution, and possible control of diseases. who, what, when , where...

epidemiology

162

_____ is the total number of deaths in a population due to a disease.

mortality rate

163

_____ is the total number of existing cases with respect to the entire population. This allows us to determine a person's likelihood of having a disease in that population.

prevalence

164

Prevalence is a measure often used to determined the level of _____ in a population.

morbidity

165

_____ measures the number of new cases over a certain time period. This allows us to determine a person's probability of being diagnosed with a disease during a given period of time.

incidence

166

_____ laid the foundations of modern epidemiology.

Florence Nightingale

167

Before the discovery of the germ theory, Florence Nightingale understood that _____ contributed to disease.

poor hygiene

168

Florence Nightingale instituted revolutionary methods in military field hsopitals, including ____ and towels fore each patient, cleaning of floors, and unclogging of sewage pipes.

separate linens

169

Florence Nightingale's notes demonstrated that more men died of disease than ____ during war.

traumatic injuries

170

An infectious disease that exhibits a relatively steady frequency over a long time period in a particular geographic locale

Endemic occurrence

171

When statistics indicate that the prevalence of an endemic or sporadic disease is increasing beyond what is expected for that population, the pattern is described as ______.

epidemic occurrence

172

When occasional cases are reported at irregular intervals in random locales. i.e.e tetanus

sporadic occurrence

173

The spread of an epidemic across continents is a ______. i.e. AIDS, influenza

pandemic occurrence

174

Koch's postulate theory has 4 exceptions.

1. some infectious agents cannot be readily isolated or grown in the lab
2. some viruses can only infect humans
3. some disease like meningitis can be caused by many different microbes
4. some diseases are not always microbial such as lung disease or liver disease.

175

There are some reasons why these Koch's postulates do not work in all situations, which Koch ____ relaize in his time.

did not

176

______ is the cause of infection and disease.

etioogic agent
i.e. vibrio cholera is the etiolgoical agent of the cholera

177

Koch's postulate theory includes a series of steps that became the standard for determining a specific disease is caused by _____.

a specific microbe
* still an essential role in modern epidemiology

178

Koch's postulates

1.There should be evidence of a specific microbe in every case of disease (and only in the sick individuals/animals)
2.You should isolate the microbe from infected individual and grow in apure culture in lab
3.Taking that pure culture, inoculate a susceptible healthy host. This should result in the same disease every time.
4.You then need to re
- isolate the same microbe from these newly infected subjects

179

First MRSA isolates identified in ___.

1960

180

_____ is resistant to methicillin and all the "-cillins" such as penicillin and ampicillin.

Methicillin-resistant Staphylococcus aureus MRSA

181

Hospital acquired (HA) MRSA became prevalen _____ to ____.

1968 to 1990s

182

The community acquired (CA) MRSA epidemic decade where the rates of HA MRSA remained stable while rates of CA-MRSA increased drastically.

1998-2008

183

First reports of healthy, young children dying of sever MRSA infections.

1999

184

_____ precautions include mask and gloves, double gloving decreases risk.

barrier precautions

185

____ include gowns, aprons, and body coverings during surgery or emergencies.

barrier precautions

186

_____ include use of puncture-proof containers for sterilization and discard. Sharps should never be recapped to reduce accidental sticks of health workers.

sharps precautions

187

_____ use germicidal soap when there is a risk of exposure.

hand washing precautions

188

______ include vaccinations when available and do not come to work when sick.

health care worker precautions

189

Top 3 most common nosocomial infections include

urinary tract
respiratory tract
surgical site infection

190

Gram ___ intestinal biota cultured in more than half of the patients with nosocomial infections. Gram ____ bacteria an yeasts make up the rest.

negative
positive

191

Recent evidence suggests that more than ____ of nonsocomial infections could be avoided by consistent and rigorous infection control methods.

1/3rd

192

Medicaid and medicare not longer reimburses hospitals for nosocomial ____, vascular catheter-associated infections, and surgical site infections, increasing their financial motivations to avoid these HAIS.

catheter-related UTIs

193

Infection control officers & stringent protocols in place in many hospital settings to help decrease ____.

HAIs

194

Nonsocomial infections are acquired as a result of a ____.

hospital stay
aka HAI or hospital acquired infections

195

Nosocomial infections are estimated to occur in 0.1 - 20% of all admitted patients, with an average of ____.

5%

196

There are ___ cases a year of nosocomial infections, resulting in approximately 90,000 deaths annually.

2-4 million cases a year

197

Infection dose verse lethal dose

?