Exam 4 - Lecture 21

Question 1

what are the main modes of pathogen transmission?

Answer 1

• airborne
• contact (direct and indirect)
• vehicle (food and water)
• vector borne (arthropod and zoonotic)
• vertical

Question 2

the disease influenza is caused by the:

Answer 2

influenza virus

Question 3

the first record pandemic of the flu was recorded in what year?

Answer 3

1580

Question 4

the worst flu pandemic killed ____ million people in 1918. it’s aka the __________ flu.

Answer 4

• 50 million
• Spanish flu

Question 5

what are the three groups of influenza?

Answer 5

A, B, and C

Question 6

true or false: influenza has a DNA segmented genome.

Answer 6

false; its an RNA virus (but yes, segmented)

Question 7

what family does the influenza virus belong to?

Answer 7

Orthomyxoviridae

Question 8

influenza virus is typically ___ segments of _____

Answer 8

8 segments of RNA

Question 9

influenza typically has how many genes/proteins?

Answer 9

11

Question 10

what are the two viral proteins in the envelope of the influenza virus?

Answer 10

• hemagglutinin (HA; 16 types)
• neuraminidase (NA; 9 types)

Question 11

strains of influenza are classified based on their combination of _______ types (H1N1, H3N2, etc.).

Answer 11

HA/NA

Question 12

in viral replication, HA attaches to _________ ______ ___________

Answer 12

sialic acid receptors

Question 13

in viral replication, NA protein does what?

Answer 13

cleaves receptors, releasing new virions

Question 14

what is antigenic drift?

Answer 14

• accumulation of mutations in a strain
• nucleotide/amino acid changes

Question 15

what is antigenic shift?

Answer 15

• reassortment of genomes (8 RNAs)
• two different strains of flu viruses infect the same cell and are incorporated into a single new capsid (like human + pig or bird strain)

Question 16

the best line of defense against influenza is:

Answer 16

vaccination

Question 17

what are two antiviral drugs found in flu vaccines?

Answer 17

• Tamiflu
• NA inhibitors (prevents release of new virions)

Question 18

what are arboviruses?

Answer 18

• arthropod-borne diseases
• viruses transmitted from one vertebrate to another by bloodsucking arthropods

Question 19

_____ _______ is spread through the bite of an infected Aedes species mosquito. it can also be spread by what?

Answer 19

• zika virus
• sex with an infected person, pregnant woman to fetus, and laboratory exposure

Question 20

many people infected with zika virus are ____________.

Answer 20

asymptomatic

Question 21

zika virus infection during pregnancy can cause:

Answer 21

microcephaly and other severe birth defects

Question 22

how does contact transmission occur?

Answer 22

• coming together or touching of source/reservoir and host
• direct and indirect

Question 23

what is direct contact transmission?

Answer 23

physical interaction between source and host
- kissing, touching, sexual contact
- contact with bodily fluids, open wounds

Question 24

what is indirect contact transmission?

Answer 24

• involves an intermediate (usually inanimate)
• eating utensils, bedding, syringes

Question 25

what does AIDS stand for?

Answer 25

acquired immune deficiency syndrome

Question 26

what causes AIDS?

Answer 26

human immunodeficiency virus (HIV)

Question 27

AIDS only develops at _______ stages of HIV infection.

Answer 27

latter

Question 28

true or false: AIDS allows opportunistic pathogens to infect.

Answer 28

true

Question 29

HIV leads to the __________ of the immune system.

Answer 29

collapse

Question 30

what family is HIV part of? what kind of genome does it have?

Answer 30

- Retroviridae family - RNA (+) virus

Question 31

how many copies of its genome does HIV have?

Answer 31

two

Question 32

the attachment of the HIV virion to human cells is mediated by _______, which attaches to CD4 receptors

Answer 32

gp120

Question 33

what are the core proteins of the HIV virion core?

Answer 33

- P24 - P17 - P9 - P7

Question 34

what is the precursor polyprotein for the virion core proteins of HIV? this polyprotein is processed by _____ __________

Answer 34

- Gag - HIV protease

Question 35

what are three important enzymes that HIV carries into the host cell?

Answer 35

- reverse transcriptase - integrase - protease

Question 36

the RNA genome of HIV is __________ transcribed into ______, which integrates into human genome as a __________.

Answer 36

- reverse - dsDNA - provirus

Question 37

true or false: HIV cannot remain latent/have asymptomatic effects.

Answer 37

false; it can totally do that

Question 38

what classifies the acute stage of HIV-related symptoms?

Answer 38

- 2-8 weeks after infection - most experience brief illness called acute retroviral syndrome - rapid multiplication and dissemination of virus throughout the body

Question 39

what classifies the chronic symptomatic stage of HIV-related conditions?

Answer 39

- viral replication continues - can last from months to years - number of CD4+ cells in blood significantly decrease

Question 40

what major groups of viruses are the main causes of gastroenteritis?

Answer 40

- rotavirus - adenovirus - astrovirus - norovirus

Question 41

what are Select Agents?

Answer 41

RNA viruses that can potentially used as bioweapons - Ebola and Marburg viruses - Rabies virus

Question 42

what family is the Ebola virus that causes Ebola hemorrhagic fever a part of? what kind of genome does it have?

Answer 42

- Filioviridae - single stranded, negative sense RNA

Question 43

Ebola hemorrhagic fever is ____% fatal and causes __________ _______________

Answer 43

- 80% - internal hemorrhaging

Question 44

what is the name of the Ebola vaccine? (page 53, lots of other info there)

Answer 44

Ervebo