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Infectious Disease and Microbiology > Viral Pathogens: Hepatitis > Flashcards

Viral Pathogens: Hepatitis Flashcards

1
Q

Hepatitis B Virus

A

Belongs to the virus family Hepadnaviridae and DNA

  • unusual partially double-stranded circular small DNA genome
  • abdominal tenderness (pain or discomfort when an affected area is touched)
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2
Q

Abdominal guarding

A

tensing of abdominal wall muscles to guard inflamed organs within the abdomen from the pain of pressure upon them

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3
Q

Hepatitis B Virus Structure

A

4 Open Reading Frames (ORFs)

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4
Q

ORF C

A

encodes the core antigen (HBcAg) which forms a protective Nucleocapsid around the genome

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5
Q

ORF S

A

encodes the surface antigen (HBsAg)

-composed of large,middle and small surface proteins present in the envelope

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6
Q

ORF P

A

encodes the polymerase enzyme

- has both DNA and RNA-dependent polymerase activities

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7
Q

ORF X

A

encode the X antigen, which is known to act as a Transactivator of transcription
-likely involved in carcinogenesis

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8
Q

A transactivator gene

A

express a transcription factor that binds to a specific promoter region of DNA
- causes that gene to be expressed.

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9
Q

When ORF C and Pre C are translated together:

A

result is HBeAg

-indicator of active viral replication.

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10
Q

HBV enters a new host via

A

genital tract or following direct inoculation of virus into the bloodstream

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11
Q

Where does HBV travel once within the blood?

A

the virus travels to the liver, where it infects the Hepatocytes

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12
Q

What does HBV do once within the liver cell?

A

the virus replicate, and new virus particles are released directly into the bloodstream
-gain access to every bodily compartment

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13
Q

Open Reading Frames (ORF)

A

part of a reading frame that has the potential to be Transcribed
-continuous stretch of codons that contain a Start codon (AUG-Methionine) and stop codon (UAA, UAG, UGA)

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14
Q

What are the three routes Hepatitis B virus is spread from person to person?

A
  • vertical transmission (mother to baby)
  • sexual transmission
  • direct blood to blood transfer of virus (parenteral transmission)
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15
Q

WHO estimates there are around _____ ______ of _____ carriers and ___ _____ in the _____

A

WHO estimates that worldwide there are around 350 millions of HBV carriers and 1.2 million in the USA

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16
Q

What are the three groups the WHO classifies countries into according to their rate of HBV carriage?

A
  • High: over 8 % of countries population are carriers
  • Intermediate: 2-7%
  • Low: under 2%
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17
Q

Host response to infection: Innate immunity

A

early stages of infection within the liver, there is IFN induction and NK cell activity.

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18
Q

Host response to infection: Adaptive immunity

A

virus encodes a number of distinct Ags

  • HBsAg
  • HBcAg
  • HBeAg: soluble protein released from infected cells, indicates active viral replication
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19
Q

Why is the production of anti-HBs antibodies important?

A

enabling the host to overcome the infection and eliminate the virus (Neutralizing Antibodies).

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20
Q

Cellular immune response

A 
lead to virus-specific Cytotoxic CD8+ T lymphocytes (CTLs)
-able to kill infected hepatocytes through recognition of viral antigens present on the infected cell surface in association with HLA class I moleucles
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21
Q

pathogenesis

A

host CTL response killing infected cells, in this way-HBV replication within hepatocytes of itself is not cytolytic and does not result in death of infected cells.
- how most damage to hepatocytes in HBV is thought to arise

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22
Q

HBV clinical presentation

A
  • 55-60% of acute HBV infections are asymptomatic (subclinical infections)
  • 1% result in fulminant hepatitis (acute liver failure)
  • 5-10% fail to clear infection and become chronic carriers
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23
Q

Symptoms of acute hepatitis B

A
  • feeling sick (malasie)
  • vomiting
  • abdominal pains
  • fever
  • jaundiced (eyes/skin)
  • dark urine and pale feces
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24
Q

In over _ out of 10 cases in adults, virus is cleared from the body by the ______ system within _ to _ months

A

9, immune. 3-6

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25
Q

In over _ out of 10 newborns infected from their mothers, virus remains ____

A

9, long term

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26
Q

Chronic HBV infection

A

proportion of patients (5-10% of adults) infected will fail to eliminate virus from liver

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27
Q

In chronic infection:

A

virus continues to replicate in infected hepatocytes

-continuously released into bloodstream

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28
Q

Chronic carriers are the

A

source of infection

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29
Q

cirrhosis

A

over time continual death of liver cells and their replacement by fibrous tissue results in complete loss of normal liver architecture and function

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30
Q

What is the average time from acute infection to cirrhosis?

A

20 years

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31
Q

What is another complication of chronic HBV?

A

development of hepatocellular carcinoma (HCC)

  • malignant proliferation of hepatocytes
  • HBV carriers are 300 times more likely to develop than individuals who aren’t carriers
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32
Q

HBV diagnosis

A

depends on detection of various markers of infection

-detect HBsAg in blood sample (positve=HBV infection)

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33
Q

core Ag

A

anti-HBc

-used to distinguish between Acute and chronic infection

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34
Q

acute infection

A

HBsAg+, IgM anti HBc +

-followed to see if they eliminate the viurs over following 6 months (disappearance of HBsAg and appearance of anti HBs)

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35
Q

If _____ persist for longer than __ months, patient is a ____ carrier

A

HBsAg, 6, chronic

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36
Q

The HBeAg/anti-HBe system distinguishes between two types of carrier

A

HBeAg+ are extremely infectious

  • Anti-HBe carrier is much less infectious, and at much lower risk of chronic liver disease
  • Anti-HBs arises in patients who clear infection and are vaccinated
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37
Q

No specific management for acute HBV infection

A

bed rest and avoid alcohol

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38
Q

In case of fulminant hepatitis what may be the only resort?

A

liver transplant

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39
Q

Carriers of HBV should be advised that

A

they’re potentially infectious

-No blood donations, share razors or toothbrushes

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40
Q

HBV vaccination

A

using the HBsAg as the immunizing
agent
-three intramuscular injections, the second and third administered 1 and 6 months after the first
-last for around 20 years
- provides greater than 90-95% protection to infants, children, an

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41
Q

Human Coronavirus

A

Enveloped non-segmented positive-sense RNA
-Named for the crown-like spikes on their surface
- First identified in 1965
-Broadly distributed in humans and other species – bats, birds, rabbits, reptiles, cats, dogs, pigs, and monkeys
-Spread by aerosol droplets and contact with infected secretions
-Survival outside the body:
+1-2 days on non-porous surfaces (e.g. hard surfaces)
+8-12 hours on porous surfaces (e.g. soft goods)

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42
Q

Community-acquired human coronaviruses (HCoVs)

A
  • 229E (alpha coronavirus)
  • NL63 (alpha coronavirus)
  • OC43 (beta coronavirus)
  • HKU1 (beta coronavirus)
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43
Q

Other human coronaviruses

A
  • severe acute respiratory syndrome coronavirus (SARS-CoV)
  • Middle East respiratory syndrome coronavirus (MERS-CoV)
  • 2019 novel coronavirus (SARS-CoV 2) causes COVID-19
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44
Q

Community acquired Human coronaviruses (HCoVs)

A
  • worldwide distribution
  • more common in winter and spring
  • responsible for 20% of common colds
  • symptoms in 50-90% of persons infected
  • more common in children
  • reinfection is common due to rapid diminution of antibody levels
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45
Q

Severe Acute Respiratory Syndrome coronavirus (SARS-CoV)

A
  • first recognized in china in November 2012
  • caused worldwide outbreak in 2012-2013
  • probable cases 8,098
  • deaths=774(10%)
  • no cases since 2014
  • originated in bats
  • transmitted to humans through civets
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46
Q

Middle East Respiratory Syndrome coronavirus (MERS-CoV)

A
  • first reported in Saudi Arabia in 2012
  • reported in 27 countries all near Arabian peninsula
  • confirmed cases 2,494
  • deaths 858
  • likely originated in bats
  • transmitted to humans through camels
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47
Q

ACE2

A

Angiotensin-Converting enzyme 2 receptor

-helps modulate the many activities of angiotensin II (ANG II) increases blood pressure, tissue injury and inflammation

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48
Q

ACE 2R

A

lung, heart, kidney, blood vessels, liver and gastrointestinal tract

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49
Q

COVID-19 clinical presentation

A
  • incubation period 2 to 14 days (average 8 days)
  • basic reproductive number R0=2.77
  • fever (83-98%) may be prolonged and intermittent
  • cough (76-82%)
  • myalgia and fatigue (11-44%)
  • sore throat in some cases
  • anosmia (loss of sense of smell)
  • headache, fatigue
  • aguesuia (diminished sense of taste)
  • less commonly: sputum production, headache, hemoptysis and diarrhea
  • asymptomatic infection in young individuals
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50
Q

Basic Reproductive Number R0

A

number of cases that are expected to occur on average in a homogeneous population as a result of infection by a single individual

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51
Q

If the average R0 is greater than 1

A

The infection will spread exponentially

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52
Q

The _________ the value of

___ , the _______ an epidemic will progress

A

Higher, R0, faster

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53
Q

COVID-19 clinical course

A
  • variable from asymptomatic infection or mild illness to severe or fatal illness
  • dyspnea in ~50% after a median
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54
Q

Between what phases does symptom onset occur in COVID-19?

A 
Incubation period (5.1 days)
Acute mild phase (5-10 days)
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55
Q

Acute mild phase

A

nonspecific symptoms

-most common:fevers, cough, myalgias, fatigue, nausea, diarrhea

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56
Q

COVID risk factors for severe illness

A

-Older patients >65 years old
-Serious chronic medical conditions such
as:
+Heart disease
+Hypertension
+Diabetes
+Lung disease
+Cancer
+Obesity BMI>30

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57
Q

COVID laboratory findings

A 
In hospitalized patients:
Ø Leukopenia (9–25%)
Ø Leukocytosis (24–30%)
Ø Lymphopenia (63%)
Ø ALT and AST levels (37%)
Ø Normal serum levels of procalcitonin
Ø Chest CT images
-Bilateral involvement in most patients
-Multiple areas of consolidation and ground glass opacities
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58
Q

What are the types of tests available for COVID-19?

A

Viral tests and antibody tests

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59
Q

Viral test

A

tells you if you have a current infection (Molecular and Antigen)

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60
Q

antibody test

A

might tell you if you had a past infection (serological)
-might not show if you have a current infection because it can take 1–3 weeks after infection for your body to make antibodies

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61
Q

True or False: Having antibodies to the virus that causes COVID-19 might provide protection from getting infected with the virus again.

A

True

62
Q

True or False: The level of immunity and how long immunity lasts against COVID are known

A

False

63
Q

Specimen Collection for Viral test

A

Nasopharyngeal swab:
Ø Use only synthetic fiber swabs with plastic shafts
Ø Don’t use calcium alginate or swabs with wooden shafts
Nasopharyngeal wash/aspirate or nasal aspirate
Ø Collect 2-3 mL into a sterile, leak-proof, screw-cap sputum collection cup or sterile dry
container

64
Q

Molecular test

A

test detects genetic material of the virus by PCR test
-health care worker collects fluid from a nasal or throat swab or from saliva
-Results may be available in a short period of time if analyzed onsite or one to
two days if sent to an outside lab
-considered very accurate

65
Q

antigen test

A

COVID-19 rapid test (LFCT) detects certain proteins that are part of the virus
-using a nasal or throat swab to get a fluid sample, antigen tests can produce results in 10-15
minutes

66
Q

_______ test result is considered very accurate, but there’s an increased chance of false _________results

A

antigen, negative

67
Q

______ tests aren’t as ________ as ________ test

A

antigen tests aren’t as sensitive as molecular tests

68
Q

COVID treatment

A

infection prevention and control measures and supportive care, including supplemental oxygen and mechanical ventilatory support

69
Q

convalescent plasma

A

at this time is an investigational product

70
Q

Regeneron’s Monoclonal antibody (Casirivimab, Indevimab)

A 
single 8 g dose of the Regeneron’s cocktail (REGN-COV2)
-Blocks attachment of viral spike protein to the human
ACE2 receptor (not very effective against the Omicron variant)
71
Q

Remdesivir

A

has in vitro activity against MERS-CoV and SARS-CoV

  • Inhibits virus RNA synthesis
  • Only drug so far FDA approved for treatment of adults and children 12 and older and weight at least 88 pounds.
72
Q

Tocilizumab

A

Monoclonal antibody that inhibits receptors for IL-6, an inflammatory cytokine released during the acute phase response
-FDA approved for rheumatologic diseases
-Emergency
Use Authorization (EUA) for adults in intensive care on high flow oxygen or ventilator support

73
Q

Dexamethasone

A

corticosteroid used for its antiinflammatory and immunosuppressant effects

  • found to have benefits for critically ill patients
  • shown to reduce mortality by about 1/3
  • patients requiring only oxygen, mortality was cut by about 1/5
74
Q

Paxlovid:

A

oral antiviral (Nirmatrelvir and Ritonavir)
-authorized for the treatment of “mild-to-moderate” COVID-19 in adults and pediatric patients with positive test at his risk for severe disease
-has 89% reduction in the risk of hospitalization and death of unvaccinated
participants
-Take the medication within 5 days of developing symptoms
-3 Paxlovid pills twice daily for 5 days for a full course (30 pills)

75
Q

Precautions for respiratory viruses

A

-Wash hands frequently soap and water for at least 20 seconds (or alcohol based sanitizer >70%)
-Cover coughs and sneezes with a tissue
-Avoid touching eyes, nose or mouth
-Cover your mouth and nose with a face mask
when around others
-Social distance (6 feet)
-stay home when sick

76
Q

failure of host defese mechanisms

A

The avoidance or subversion of a normal immune response by pathogens

77
Q

Why do most successful pathogens persist?

A
  • they don’t elicit an immune response

- they evade the response once it has occurred.

78
Q

Why do inherited failures of immune defenses occur?

A

Genetic defects

79
Q

Acquired Immune Deficiency Syndrome (AIDS)

A

generalized susceptibility to infection that it is itself due to the failure of the host to control and eliminate the Human Immunodeficiency
Virus (HIV)

80
Q

Immunodeficiency diseases

A

defective gene results in the elimination of one or more components of the immune system

  • Defects in T- or B-Lymphocytes development,
  • Defects in phagocyte function,
  • Defects or absence of complement components
81
Q

antigenic variation

A

Allows Pathogens to Escape from Immunity
-particularly important for extracellular pathogens, which are generally eliminated by antibodies against their surface structures.

82
Q

3 main forms of antigenic variations

A
  1. Many infectious agents exist in a wide variety of antigenic types distinguish by their different serotypes
  2. antigenic drift and shift
  3. Programmed gene rearrangement
83
Q

antigenic drift

A

point mutation in the main surface H protein of the virus
-involves the emergence of point mutants with
altered binding sites for protective antibodies
-new virus can grow in a host that is immune to the previous strain of virus, but as T-cells and some antibodies can still recognize epitopes that have not been altered, the new variants cause only mild disease in previously infected
individuals

84
Q

Antigenic shift

A

due to major changes in
the hemagglutinin of the virus which can cause global pandemics of severe diseases as the new hemagglutinin
(antigenic glycoprotein) is poorly recognized
-is a rare event involving the reassortment of the segmented RNA viral genomes of two different influenza virus

85
Q

programmed gene rearrangement

A

which involves periodic switching of the major cell surface protein (variable surface glycoprotein)

86
Q

How many types of influenza virus are there?

A

3

-A,B and C

87
Q

Human influenza A and B viruses cause

A

seasonal epidemics of disease almost every Winter in the US

88
Q

Influenza type C

A

infections cause a mild respiratory illness and are not thought to cause epidemics

89
Q

Influenza A viruses

A

divided into subtypes based
on 2 proteins on the surface of the virus: Hemagglutinin (H) and Neuraminidase (N)
-Broken down into different strains: H1N1 and H3N2

90
Q

How many different Hemagglutinin subtypes are there?

A

18

91
Q

How many different Neuraminidase subtypes are there?

A

11

92
Q

Neutralizing antibodies

A

mediate protective immunity which is directed at the viral surface protein Hemagglutinin (H), which is responsible for viral binding to and entry into cells

93
Q

Latency

A

virus is not being replicated

  • in latent state virus doesn’t cause disease but it can not be eliminated (no viral peptides to signal its presence)
  • Latent infections can be reactivated resulting in recurrent illness
  • ex Herpes Simplex Virus (HSV-1, oral herpes)
94
Q

Herpes Simplex Virus (HSV-1, oral herpes)

A

infects epithelial cells and spreads to sensory
neurons serving the infected area
-initial infection in the skin is cleared by an effective immune response, but residual infection persists in sensory neurons such as those of the trigeminal ganglion, whose axons innervate the lips
-virus is reactivated, usually by some environmental stress and/or alteration in immune status

95
Q

active immunity

A

conferred by natural exposure to an infectious agent

  • depends on the action of a person’s own Lymphocytes and the resulting Memory cells specific for the invading pathogen
  • can develop following immunization (vaccination)
96
Q

First vaccine

A

consisted of the virus causing Cowpox

97
Q

cowpox virus (CPXV)

A

protects against Smallpox virus or variola virus because the two viruses are so similar that the immune system cannot distinguish them

98
Q

Vaccine is an example of

A

Artificially-acquired active immunity

99
Q

Vaccines include

A

inactivated bacterial toxins (Toxoid vaccines), killed microbes, parts of microbes,
viable but weakened microbes that generally do not cause illness, and even genes encoding
microbial proteins

100
Q

Reasons more measles outbreaks can occur

A
  • increase in the number of travelers who get measles abroad and bring it into the U.S., and/or
  • further spread of measles in U.S. communities with pockets of unvaccinated people.
  • majority of people who got measles were unvaccinated
101
Q

fundamental principle of vaccination

A

to administer a killed or attenuated form of an infectious agent, or a component of a microbe, that doesn’t cause disease but elicits an immune response that provides protection against infection by the live, pathogenic microbe

102
Q

Vaccine success depends on

A
  • Vaccines are effective if the infectious agent does not establish latency
  • If it does not undergo much/any antigenic variation -If it does not interfere with the host immune response
  • Vaccines are also most effective against infections that are limited to human hosts and do not have animals reservoirs
103
Q

humoral immunity

A

inducing antibodies against the pathogen

-how most vaccines in use today work

104
Q

Diseases that effective vaccine is still needed

A

malaria, schistosomiases, intestinal worm infestation, tuberculosis, diarrheal disease, respiratory infections, HIV/AIDS

105
Q

effective vaccine for extracellular organisms

A

Antibodies provide the most important adaptive mechanisms of host defense

106
Q

effective vaccine for intracellular organisms

A

CD8 T-cell response

107
Q

Ideal vaccine

A

provides host defense at the point of entry of the infectious agent
-stimulation of Mucosal Immunity is therefore an important goal of vaccination against those many organisms that enter through mucosal surfaces

108
Q

Vaccine must

A

-be safe, low level of toxicity is unacceptable
-must be able to produce protective immunity in a very high proportion of the people to whom it is given
-generate Long-Lived Immunological Memory.
o must prime T and B-lymphocytes.
-Must be relatively cheap if they are to be administered to large populations

109
Q

Adjuvants activate

A

APC (antigen presenting cells) by engaging the Innate Immune System and providing ligands for Toll-like and other receptors on APC cells

110
Q

adjuvants

A

mixed with the Antigen and usually render it particulate

  • helps to retain the antigen in the body and promote uptake by macrophages
  • most include bacteria or bacteria components that stimulate macrophages, aiding in the induction of the immune response
111
Q

Incomplete freunds adjuvant

A
  • oil in water emulsion
  • delayed release of antigen
  • enhanced uptake of macrophages
112
Q

complete freund’s adjuvant

A
  • oil in water emulsion with dead mycobacteria
  • delayed release of antigen
  • enhanced uptake by macrophages
  • induction of co-stimulators in macrophages
113
Q

freunds’ adjuvant with MDP

A

oil in water emulsion with muramyldipeptide (MDP), constituent of mycobacteria
-similar to complete freund’s adjuvant

114
Q

alum (aluminum hydroxide)

A

aluminum hydroxide gel

  • delayed release of antigen
  • enhanced macrophage uptake
115
Q

alum plus bordetella pertussis

A

aluminum hydroxide gel with killed B.pertussis

  • delayed release of antigen
  • enhanced uptake by macrophages
  • induction of co-stimulators in macrophages
116
Q

immune stimulatory complexes (ISCOMs)

A

matrix of Quil A containing viral proteins

  • delivers antigen to cytosol
  • allows induction of cytotoxic T cells
117
Q

Most antiviral vaccines

A

currently in use consist of Inactivated or Live Attenuated viruses

118
Q

first generation vaccines

A

viral vaccines consist of viruses treated so that they
are unable to replicate
-Inactivated, or killed
-peptides from the viral antigens can not be presented by MHC class I molecules and thus CD8+ cells are not generated by these vaccines
-ex flu vaccine

119
Q

second generation vaccines

A

generally far more potent, because they elicit a greater number of relevant effector mechanisms

  • Live-attenuated viral vaccines
  • ex polio, measles, mumps, rubella, varicella and the “nasal spray flu vaccine”.
120
Q

attenuation

A

achieved by growing the virus in cultured cells. to produce an attenuated virus
-virus must first be isolated by growing it in cultured human cells

121
Q

Flu vaccine

A

-inactivated or killed is widely used
-everyone 6 months of age and older is a candidate
-quadrivalent (four components) inactivated (killed) vaccine that is used
in the flu shot that is given intramuscularly (IM).
-live attenuated virus and is used as a Nasal spray
-designed to protect against main flu virus

122
Q

trivalent (three-component) egg-based vaccines are recommended to contain:

A

A/Guangdong-Maonan/SWL1536/2019 (H1N1)pdm09-like virus (updated)
A/Hong Kong/2671/2019 (H3N2)-like virus (updated)
B/Washington/02/2019 (B/Victoria lineage)-like virus (updated)

123
Q

Quadrivalent (four-component) egg-based vaccines, which
protect against a second lineage of B viruses, are recommended
to contain:

A

the three recommended viruses above, plus B/Phuket/3073/2013-
like (Yamagata lineage) virus.

124
Q

Bacille Calmette-Guerin (BCG)

A

Live Attenuated vaccine derived from Mycobacterium bovis

  • closely related to Mycobacterium tuberculosis
  • provides protection against the more severe types of tuberculosis
  • freeze-dried and need to be mixed with the correct diluent from the same manufacturer before administration
125
Q

BCG dose

A

vial with 20 doses, dose for a new born is 0.05 ml

126
Q

BCG route

A

ID into the Right arm
BCG vaccine vials must be discarded 6 hrs after mixing.
BCG can give up to babies 1 year old.

127
Q

human paillomavirus (HPV)

A

comprise a family of double-stranded DNA (dsDNA) viruses

  • causes several different infections
  • Many infections are asymptomatic but some progress to genital warts
  • Can cause cervical neoplasia, and a few progress to cervical cancers
  • Diagnostic: genital warts, PAP and DNA tests
128
Q

Most HPV infections resolve

A

spontaneously but as with many viral infections, there is no adequate treatment or cure for active infections

129
Q

Genital warts are most commonly caused by types

A

6 and 11

130
Q

Cervical cancer is the result of persistent oncogenic types of HPV

A

16, 18, 31,33,45

131
Q

Gardasil 9

A

non-infectious recombinant vaccine prepared from the purified VLPs of the major capsid(L1) protein of HPV types 6, 11, 16, 18, 31, 33, 45, 52, and 58

132
Q

DNA vaccines

A

circular or linear plasmids that encode an Antigenic Protein (AP) from a
pathogen that is directly injected into the cells.
-after vaccine is injected into patients the plasmid is taken up by cells at the site of injection
-Inside the cell, the viral genes are expressed into
protein
-The viral proteins are degraded into small peptide fragments, which are then presented by MHC class I molecules

133
Q

DNA vaccines represent a favored vaccine strategy because

A

they are safe, stable, easy to engineer and
produce, an immune response which pose no
interference against later boost immunizations
-disadvantage: DNA vaccines are poor (weak) in terms of Immunogenicity compared to 1st and 2nd generation vaccines

134
Q

gene expression

A

increased by optimizing both the coding sequence and the gene regulatory elements

135
Q

traditionally DNA has been delivered

A

by injection or gene gun into muscles or skin, or administration into nasal or oral cavity

136
Q

Novel delivery technologies include use of

A

-Bacterial and viral vectors
-Particle-mediated delivery into Antigen Presenting Cells (APC) using lipid polymers
-Gold microparticles that encapsulate and condense the DNA allowing slow release
-Physical delivery methods such as:
+electroporation
+needle-free devices such as epidermal patches

137
Q

electroporation

A

electrical pulses causes temporary and reversible pores in the protective membranes of the cells such as skin, muscle and APC cells
-It can increase the entrance of the plasmids inside the cells by a 1,000 or more

138
Q

Immune responses are modulated by addition of

A
  • Co-stimulatory molecules such as ICAM-1 and CD40L
  • Genes encoding cytokines such as IL-12 and GM-CSF
  • Chemokines such as RANTES (Regulated on activation, normal T cell expressed and secreted) and MIP-1α (Macrophage Inflammatory Proteins); and
  • TLR ligands such as CpG oligonucleotides and heat-shock proteins.
139
Q

No ____ vaccines have been approved for _____ use in the US

A

DNA, human

140
Q

DNA vaccines

A
  • Uses only the DNA from infectious organisms.
  • Avoid the risk of using actual infectious organism.
  • Provide both Humoral & Cell mediated immunity
  • Refrigeration is not required
  • Low immunogenicity
141
Q

Traditional vaccines

A

Uses weakened or killed form of infectious
organism.
-Create possible risk of the vaccine being fatal.
-Provide primarily Humoral
immunity
-Usually requires Refrigeration
-Higher immunogenicity

142
Q

RNA vaccines

A

give instructions to our cells to make a harmless piece of a viral protein
-vaccine can be given in the upper arm muscle
-Once the instructions are inside the muscle or the immune cells, the cells use them to make the protein piece. After the protein piece is made,
the cell breaks down the instructions and gets rid of them
-immune systems recognize that the protein doesn’t belong there and begin building an immune response and making antibodies

143
Q

Pfizer-BioNTech

A

Doses: 2 (21 days apart)
Effectivity: 95%
Storage: 80 C, distributed in a five-dose vial, must be diluted in 0.9 NaCl
before administered
Approve to use in: people over the age of 16
Side Effects : Injection site reaction, Fatigue, Headache, Muscle pain, Chills, Joint pain, Fever

144
Q

Moderna

A

Doses: 2 (28 days apart)
Effectivity: 94.5%
Storage: 20 C, distributed in a ten dose vial, it does not need to be diluted before administered.
Approve to use in: people over 18
Side Effects: Injection site pain, Fatigue, Headache, Muscle pain, Chills, Joint pain

145
Q

J & J

A

Doses: 1
Effectivity: 74%
Storage: 4C, distributed in a 5
doses vial, it does not need to be diluted before administered
Approve to use in: People over 18
Side effects: Injection site pain, Fatigue, Headache, Muscle aches, nausea

146
Q

CDC recommendation for J&J vaccine

A

not recommend for women < 50 years

-6.8 million doses of J&J vaccines and 6 cases of Blood clots after receiving the vaccine

147
Q

Novavax

A 
Doses: 2 (three weeks apart)
Effectivity:
-90.4%
->65 years: 78.6%
Approve to use in: over 18
Side effects: pain/tenderness, redness and swelling at the injection site, fatigue, muscle pain, headache, joint pain,
Allergic reactions
storage: Unopened vials 6 months at 2C to 8C
148
Q

passive immunity

A

transferring Antibodies from an individual who is immune to a particular infectious agent to someone who isn’t
-doesn’t result from the action of the recipient’s own
B and T-cells
-provides immediate protection, but it persists only as long as the transferred antibodies last (a few weeks to a few months)

149
Q

Passive immunization occurs

A

naturally when IgG antibodies of a pregnant woman cross the
placenta to her fetus
-IgA antibodies are passed from a mother to her nursing infant in breast milk
-help protect the infant from infection while the baby’s own immune system is maturing

150
Q

Passive immunization ________ induce memory,

A

does not

151
Q

active immunity

A

specificity: yes
memory: yes

152
Q

passive immunity

A

specificity: yes
memory: no

Infectious Disease and Microbiology (9 decks)

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