Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Multisystem Part 2 > viral bio weapons > Flashcards

viral bio weapons Flashcards

1
Q

viral hemorrhagic fevers (in general)

A

severe multisystem syndromes

the overall vascular system is damaged, and the body’s ability to regulate itself is impaired.

often accompanied by hemorrhage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what kind of virus is Lassa fever?

A

arenavirus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what kind of virus is CCHF (congo crimean hemorrhagic fever)

A

bunyavirus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what kind of virus is ebola?

A

filovirus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what kind of virus is yellow fever?

A

flavivirus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what kind of virus is marburg?

A

filovirus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what kind of virus is hantaviruses (HFRS and HPS)?

A

bunyaviruses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

properties of VHF agents (viral hemorrhagic fever agents)

A

all are enveloped RNA viruses dependent on animal or insect host

patient history includes: foreign travel, rural env, animal exposure

no cure or established treatment

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Leptospirosis

A

bacterial VHF vasculitis + hemrrhagic rash

d/t leptospira

with enlargement of spleen, jaundice and nephritis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

waterhouse-friderichsen syndrome

A

bilateral, hemorrhage into the adrenal glands caused by fulminant meningococcemia.

characterized by: (1) overwhelming bacterial infection (2) Rapid hypotension leading to shock (3) DIC (disseminated intravascular coagulation) with widespread purpura

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

HUS

A

occurs after bloody diarrhea caused by E. coli O157:H7, a strain that expresses verotoxin (also called Shiga toxin).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

hemolysis –> dark urine “black water fever” is d/t…

A

falciparum malaria

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

usually treatment for a VHF is based on

A

supportive care

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

can maybe treat arenaviruses and bunyaviruses (CCHF, Hantaviruses, RVF) with

A

ribavirin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what VHFs have vaccines?

A

yellow fever and argentine hemorrhagic fever

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

how lethal is ebola virus?

A

up to 90%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

ebola and marburg

A

filoviruses

long, sometimes branched filaments, shorter filaments shaped like a “6”, a “U”, or circles.

they are enveloped ssRNA - sense

18
Q

likely reservoir of ebola?

A

bats in africa

19
Q

which ebola subtype is not pathogenic for humans?

A

reston type; the other four are!

20
Q

transmission/diagnosis of ebola

A

Infections are acute = no carrier state.

Transmitted by direct contact with blood and secretions of an infected person, and through contaminated needles etc.

Diagnosis: difficult in early stages because of non-specific early symptoms (e.g. red eyes and a skin rash).

21
Q

CCHF

transmission and vector

A

crimean congo hemorrhagic fever

transmitted by hyalomma tick

or contact with animal pre/post slaughter

-

22
Q

virus that causes CCHF

A

a bunyavirus

genome is circular, ambisense RNA (+ and -) in three parts - Small (S), Middle (M) and Large (L).

23
Q

Lassa fever and S. american hemorrhagic fevers (LCMV)

A

arenaviruses

rodent hosts

virions are envelped and have a grainy appearance due to ribosomes

genome has 2 strands of ambisense RNA (some + and some -; S and L)

24
Q

Lassa fever (arenavirus)

transmission

A

Contact with rodent (rats) excreta - contaminated food, broken skin, inhalation of tiny particles soiled with rodent urine or saliva (aerosol transmission)

virus is shed in the urine and feces

**can be rodent to human or human to human(body fluids)

25
Q

Lassa fever

A

caused by arenavirus Lassa

Rodent reservoir –Mastomys (“multimammate rat)”

26
Q

signs and symptoms of lassa fever

A

Occur 1-3 weeks after infection

Fever, retrosternal pain, sore throat, abdominal pain, vomiting, diarrhea, conjunctivitis, facial swelling, and mucosal bleeding. Neurological signs also seen

Most common complication of Lassa fever (1/3 cases) is deafness.

27
Q

most common complication of lassa fever is

A

deafness

28
Q

swollen baby syndrome

A

lassa fever in infants

Edema, Abd distension, & Bleeding = Poor prognosis

Treatment: supportive care & Ribavirin

29
Q

A 50-year-old man from Sierra Leone who has been living in the US but went home for a week to visit his family, presents to your clinic with fever, chills and multiple joint pain. He informs you that he spent five days in his rural home village sleeping in a hut. There were rats running through the hut, and some dead rats on the floor. He tells you that his symptoms began on the day he flew back to New York city five days earlier. The patient receives symptomatic treatment and blood samples are taken. Considering his travel history and his symptoms the hospital staff suspect a viral hemorrhagic fever. By the fifth day after admission, conjunctival, nasal, and oral petechial hemorrhages are evident and three hospital staff and two other patients in the ward become ill with similar symptoms and one later dies. The traveler MOST LIKELY was infected by

A. smallpox virus.

B. yellow fever virus.

C. a non-enveloped small DNA virus.

D. Lassa fever virus.

E. Dengue virus.

A

D

Major clues: Traveler’s history; West Africa, along with clinical signs. Rural village with presence of rats/dead rats. Most likely ‘viral’ cause of his hemorrhagic fever is Lassa fever which is present in this location, has incubation period consistent with case (5 to 21 days) and is transmitted by rodents via aerosol/contaminated dust.

Ans (A) is incorrect for many reasons such as smallpox has been eradicated and the patient recovered with no vesicular lesions; (B) and (E) are incorrect because both yellow fever and dengue are transmitted by mosquito vectors and this unlikely to occur in the NYC hospital. Ans (C) is incorrect because no small non-enveloped DNA virus is known to be associated with this disease scenario.

30
Q

poxviruses

size?

composition?

genome?

features?

A

Size: BIG brick-shape particle

Genome (very large): Double-stranded, linear DNA. The only DNA virus that replicates solely in the cytoplasm

Largest and most complex virus; resistant to inactivation

31
Q

poxvirus replication is under what type of regulation?

how does this work?

A

temporal regulation

vaccinia virus RNA polymerase requires a separate set of virus-encoded proteins for the transcription of the early, intermediate and late classes of genes

**early mRNA creates early enzymes and intermediate transactivators; intermediate mRNA creates late transactivators and late mRNA

32
Q

small pox transmission

A
  • Spread by secretions from mouth & nose and by pocks or scabs
  • Thus, transmission requires close contact with patients or their clothing or bedding
33
Q

a disfiguring disease?

A

small pox

34
Q

progression of smallpox rash

A

day 1 - a few papules/raised spots (2-4 days after a fever); seen first on the face then on the body

day 2 - more papules; differ in size but same appearrance

day 3 - beginning of vesicles (fluid accumulation and raised)

day 4 - distinct vesicles; firm to touch; when broken dont collapse since fluid is in multiple compartments

day 5 - flluid is cloudy and looks like pus; pocks are now called pustules; fever rises and feeling more ill

day 7 - obvious pustules; all similar appearring; no mistake in diagnosis

(picture shows day 4,5, and 7)

day 8/9 - pustules are firm and embedded

day10-14 - pustules dry up and dark scabs form; scabs contain LIVE smallpox virus; patient is infective until all scabs have fallen off

day 14-20 - by day 20 all the scabs are off and light colored areas are observed; skin returns to normal over a week, however scars may remain for life

35
Q

when are smallpox patients infectious?

A

scabs contain LIVE smallpox virus; patient is infective until all scabs have fallen off

36
Q

where are lesions/pustules distributed in small pox?

A

face, palms/soles and extremities

less dense on the trunk

37
Q

chicken pox vs small pox lesion distributions

A

in smallpox they are present on the palms and soles (denser on extremities)

in chickenpox, they are NOT (denser on body, fewer on extremities)

38
Q

small pox diagnosis

A

gentian violet stain –> Guarnieri bodies (typical inclusions).

Electron microscopy –> brick shaped virions.

39
Q

5 features that make a virus suitable for eradication

A
  1. No animal reservoir.
  2. Lack of recurrent infections.
  3. One or few stable serotypes.
  4. Availability of an effective vaccine.
  5. Absence of subclinical infections.
40
Q

smallpox vaccine

A

made from vaccinia

contains live virus; similar virus but doesnt cause smallpox

can have bad side effects

41
Q

human vaccinia immune globulin (hVIG)

A

used to treat adverse reactions from vaccinia (smallpox vaccine)

Multisystem Part 2 (20 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions