pathogenic viruses

Question 1

non segmented negative strand RNA viruses

Answer 1

Paramyxoviridiae
Rhaboviridae
Filovirdiae

Question 2

paramoxyviridea pathogens

Answer 2

respiratory measles and mumps

Question 3

paramoxyvirdia structure

Answer 3

Viral RNA
HN/H/G (Hemagluttin -neuraminidase
F (fusion protein)
L (RNA polymerase)
N (nucleocapsid)

Question 4

measles virus

Answer 4

acute childhood disease
most contagious
high mortalitiy in developing countries
1 serotype
cold like symptoms and Koplik spots that turn to rash
conjunctuvitis (pink eye)
MMR vaccine

Question 5

mumps virus

Answer 5

1 serotype
swollen salivary glands and fever
MMR vacine

Question 6

rhaboviridiae

Answer 6

rabies -acute fatal viral inflammation of brain
enveloped virus
bullet shape
death by respiratory paralysis
virus can stay in the muscle for months or years before reaching peripheral nerves and going systemic
once symptoms occur there is no cure and 100 percent fatality
before symptoms you can get the vaccine and passive immunoglobin

Question 7

rabies diagnosis

Answer 7

easier to detect after death in brain b/c negri bodies seen in Purkinje cells
direct flourescent antibody test
before death several test are needed to diagnose

Question 8

filoviridiae

Answer 8

ebola virus -filamentous virion

Question 9

ebola virus

Answer 9

4 subtypes and 3 of them cause human disease

resovoir most likely bats

Question 10

what does flu vs a cold affect?

Answer 10

flu affects both upper and respiratory tract

cold affects only upper respiratory tract

Question 11

children vs adults in influenza

Answer 11

children shed virus for weeks vs days for adults

Question 12

who are at high risk of influenza?

Answer 12

children especially >1 yr
elderly
adults with underlying health problems
pregnant women

Question 13

complications of influenza?

Answer 13

pneumonia

excaberate chronic health problems

Question 14

properties of influenza?

Answer 14

enveloped virion
genome is segmented, negative, single stranded RNA
receptor is saliac acid
H hemagglutinin binds to receptor

Question 15

what is necessary for influenza infection?

Answer 15

binding of saliac acid with viral H needed to bind and infect
after budding viral enveloped contains both H and sialic acid

Question 16

neurominidase

Answer 16

cleaves sialic acid to aid in viron release

mucous contains a lot of sialic acid to bind and trap to the virus but neurominidase prevents this trap.

Question 17

influenza virulence factors

Answer 17

H - hemagluttinin binds receptor
N - neurominidase cleaves sialic acid
M2 - ion channel allows uncoating by decreasing pH of virion

Question 18

antigenic shift vs drift

Answer 18

antigenic shift = abrupt changes by reassortment (segmented virus)
antigenic drift = gradual changes by mutation and error prone polymerase. mutation in antibody binding sites on H

Question 19

H hemagluttinin

Answer 19

evolves rapidly

16 H subtypes

Question 20

mixed infection is caused by?

Answer 20

antigenic shift

cause pandemics

Question 21

retroviridiae

Answer 21

rna/dna virus
reverse transcription
integration part of life cycle
high evolution rate

Question 22

lentivirus

Answer 22

HIV
cause chronic progressive disease
replicate in nondividing cells and kill cells
envelope virus

Question 23

HIV virion structure

Answer 23

genome: 2 identical copies of RNA strand non segmented

3 enzymes in caspid are; reverse transcriptase, integrase, protease

Question 24

what does hiv deplete?

Answer 24

HIV depletes CD4 + T cells