VIRAL INFECTIONS

Answer 1

Viral Hepatitis
HIV
Dengue
Herpes Virus infections: infectious mononucleosis, Epstein Barr Virus, Cytomegalovirus

Question 2

Submicroscopic particle (size is measured in nanometers)

Answer 2

VIRUSES

Question 3

VIRUSES

Demonstrated using (?) (compound for bacteria)

Answer 3

electron microscope

Question 4

VIRUSES Basic Structure:

Answer 4

core of DNA or RNA

Question 5

DNA or RNA is packed in (?) and some virus’s capsid is surrounded by outer envelope such as (?)

Answer 5

protein coat or capsid

glycolipids and proteins.

Question 6

Intracellular pathogens

Answer 6

VIRUSES

Question 7

They are going to rely on (?) for replication and survival.

Answer 7

host cells

Question 8

No host =

Answer 8

dormant

Question 9

First line of protection (nonspecific immunity)

Answer 9

INNATE IMMUNITY

Question 10

(virus-infected cells; produced in the recognition of TLRs)

Answer 10

Interferon-a and Interferon-b

Question 11

Inhibits viral replication

Answer 11

INNATE IMMUNITY

Question 12

Inhibits viral replication

Answer 12

INNATE IMMUNITY

Question 13

HUMORAL DEFENSE
– primary cells involved

Answer 13

B cells and plasma cells

Question 14

Produces virus specific antibodies

Answer 14

HUMORAL DEFENSE

Question 15

Ab prevents spread of viral replication through neutralization

Answer 15

HUMORAL DEFENSE

Question 16

: promotes phagocytosis thru opsonization

Answer 16

IgG

Question 17

: Agglutinates viral particles

Answer 17

IgM

Question 18

Upon activation of (?), CD8+ Cytotoxic T cells (CTL) become programmed to expand in number and attack the virus-infected cells.

Answer 18

CD4+ T helper cells and cytokines

Question 19

produce proteins and proteases

Answer 19

Cytotoxic T cells (CTL)

Question 20

proteases

Answer 20

Perforinm
Granzymes

Question 21

• pore forming protein; create a pore in the membrane of the host cell

Answer 21

Perforin

Question 22

• they will now enter the pore and will activate apoptosis

Answer 22

Granzymes

Question 23

CELLULAR DEFENSE

Increase (?) its original number

Answer 23

50,000 times

Question 24

STRATEGIES ON HOW VIRUSES ESCAPES IMMUNE MECHANISMS

Answer 24

They undergo frequent genetic mutations

Some viruses can evade actions of the component of the immune response

Viruses can evade the hosts defense by suppressing the immune system

Question 25

– not recognized immediately by initial immune response

Answer 25

Produces new viral antigens

Question 26

LABORATORY TESTING FOR VIRAL INFECTION

Answer 26

Virus specific IgM antibodies

IgG antibodies to the virus

Question 27

Indicates current or recent infection or acute infection

Answer 27

Virus specific IgM antibodies

Question 28

Specific IgM antibody in newborns indicates (?) with virus

Answer 28

congenital infection

Question 29

Indicates current or past infection and in most cases immunity

Answer 29

IgG antibodies to the virus

Question 30

IgG antibodies in newborns are mainly (?)

Answer 30

maternal antibodies

Question 31

can cross the placenta; thus normal

Answer 31

IgG

Question 32

infects the host cell by attaching to specific receptors in their target cells

Answer 32

Virion

Question 33

It penetrates the

Answer 33

cell membrane

Question 34

Release of

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nucleic acid (RNA or DNA)

Question 35

directs the host cell machinery to produce more viral nucleic acid and proteins

Answer 35

nucleic acid (RNA or DNA)

Question 36

assemble inside the cell to form the intact virus, which is released thru (?) of the cell surface

Answer 36

cell lysis or budding

Question 37

Viruses destroy the cells leading to

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decreased cell count

Question 38

Target cell:

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CD4 T cells

Question 39

By inducing transcription of several genes that will code for proteins w/ antiviral activity

Answer 39

Inhibits viral replication

Question 40

Binds virus-infected cells and release cytotoxic proteins like perforin (substance that create pores) and granzymes

Answer 40

Enhances activity of NK cells

Question 41

antibodies specific for a component of the virus that binds to a receptor on the host cell membrane will bind to the virus and prevent it from attaching to and penetrating the cell

Answer 41

Produces virus specific antibodies

Question 42

antibodies neutralize viruses in the mucosal surfaces

Answer 42

Secretory IgA

Question 43

can bind to viruses in the bloodstream and inhibit dissemination of the infection.

Answer 43

IgM and IgG antibodies

Question 44

promote phagocytosis of viruses through their opsonizing activity

Answer 44

IgG antibodies

Question 45

can also inactivate viral particles by agglutinating them.

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IgM antibodies

Question 46

also activate complement

Answer 46

IgG and IgM antibodies

Question 47

leading to elimination of intracellular viruses required for replication

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Cytotoxic T cells (CTL)

Question 48

Ex. Covid-19
 Frequently undergo genetic mutation due to presence of nucleic acids
 Production of new viral antigens that are not recognized immediately by the innate immune response

Answer 48

They undergo frequent genetic mutations

Question 49

For example, the Hepatitis C virus (HCV) can block the degradation of viral RNA that is induced by interferons.

Answer 49

Some viruses can evade actions of the component of the immune response

Question 50

For example, cytomegalovirus and human immunodeficiency virus can reduce the expression of major histocompatibility complex molecule on the surface of virus infected cells making them less likely to be recognized by B cells

Answer 50

Viruses can evade the hosts defense by suppressing the immune system

Question 51

LABORATORY TESTING FOR VIRAL INFECTION

Answer 51

Serologic testing
Molecular assays

Question 52

– monitors the course of infection, detects past infection, can assess immune status

Answer 52

Serologic testing