RNA viruses Flashcards

1
Q

Reoviruses

A

No ENV, DS linear, 10-12 segments,
Isocahedral(double)

Coltivirus-Colorado tick fever
Rotavirus-#1 cause of fatal diarrhea in children

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

Picornavirus

A

No ENV, ss + linear, icosahedrral

Polio
Echovirus: aseptic meningitis
Rhinovirus: common 
Coxsackies: aspetic meningitis, herpangina (mouth blisters, fever), hand, food and mouth disease, myocarditis
HAV: acute viral hepatitis

PERCH

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

Hepevirus

A

NO ENV, ss + linear, icosahedral

HEV

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

Calcifivirus

A

NO EVN, ss + linear, icosahedral

Norovirus-viral gastritis

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

Flavivirus

A
ENV, ss + linear, icosahedral
HCV,
Yellow fever
Dengue,
St. Louis encephalitis
West Nile virus
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Togavirus

A

ENV, ss + linear, icosahedral

Rubella
Eastern equine encephalitis
Western quine encephalitis

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

Retrovirus

A

ENV, ss + linear, icosahedral (HTLV) vs complex and conical (HIV)

Have RT
HTLV- T cell leukemia
HIV-AIDS

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

Coronavirus

A

ENV, ss + linear, helica

Common cold and SARS

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

Orthomyxoviruses

A

ENV, ss - linear, helical, 8 segments

Influenza

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

Paramyxoviruses

A

ENV, ss - linear, helical, nonsegmented

Parainfluenza = CROUP
RSV= bronchiolitis in babies, treat with ribavirin
Measles
Mumps

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

Rhabdovirus

A

ENV, ss - linear, helical

Rabies

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

Filovirus

A

ENV, ss - linear, helical

Ebola/Marburg hemorrhagic fever

often FATAL

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

Arenaviruses

A

ENV, ss - linear, helical, 2 segments

LCMV-lymphocytic choriomeningitis virus
Lassa fever encephalitis: spread by mice

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

Bunyaviruses

A

ENV, ss - linear, helical, 3 segments (vs. Arena with 2)

California encephalitis
Sandfly/Rift valley fevers
Crimean-Congo hemorrhagic fever
Hantavirus-hemorrhagic fever, pneumonia

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

Delta virus

A

ENV, ss - linear, Uncertain

HDV is defective virus that requires HBV.

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

Negative stranded viruses

A

Must transcribe negative to positive
Must bring its own RNA dependent RNA pol

Arenavirus, buynavirus, paramyxo, orthomyxo, filovirus, and rhabdovirus

“Always Bring Polymerase Or Fail Replication”

17
Q

Segmented viruses

A

All are RNA viruses
Bunya, orthomyxo, arena, and reoviruses

“BOAR segments”

18
Q

Picornavirus

A

PERCH

RNA translated into a large polypeptide leaved by proteases.

Can cause aseptic viral meningitis (except rhino and HAV)

All are entero (fecal oral) except rhinovirus

19
Q

Rhinovirus

A

Picnoa
Non enveloped RNA
Common cause of cold, >100 serotypes
Acid labile, therfore does not infect the GI

20
Q

Yellow fever

A

Flavivirus and arbovirus
Transmitted by Aedes mosquitos
Monkey and human reservoir

Symptoms: high fever, black vomitus, and jaundice

Flavi: means yellow and jaundice

21
Q

Rotavirus

A

Most important global cause of infantile GI
Segmented RNA, reovirus

Major cause of acute diarrhea in the US during winter esp in dare care centers

Villous destruction with atrophy leads to decreased absorption of Na and loss of K+

22
Q

Influenza

A

Enveloped, negative single stranded with 8 segments
HA: promotes viral entry
NA: promotes viral eggress

Patients at risk for fatal bacterial superinfection

Shift: assortment of genomes, causes PANDEMIC
Drift: minor changes, causes EPIDEMIC

“Sudden shifts are more deadly than graDual Drift”

23
Q

Rubella virus

A

Togavirus
Cause rubella, one know as German measles (3day)

Fever, posauricular adenopathy, LAD, arthralgia, fine TRUNKAL rash that starts at HAND move moves DOWN
(Vs. Scarlett fever with face sparing)
“Rub-ear=postauricular, rubella”

Causes mild disease in children but serious congenital disease.

24
Q

Paramyxoviruses

A

Paramyxovirus cause disease in children

Parainfluenza: croup: bark like cough
RSV: bronchiolitis, pneumonia
Mumps and measles

All contain surFace protein F (fusion) protein, which causes respiatory epithelial cells to fuse and form multinucleated cells

Palivizumab (antibody against F protein) prevents pneumonia caused by RSV in premature infants.

25
Q

Measles virus

A

Paramyxo

Koplit spot and descending maculopapular rash

Possible sequelae: SSPE (subacute sclerosing panecephalitis, occuring years later), encephalitis (1:2000), and giant cell pneumonia (rarely, in immunosuppressed)

Rash presents LAST and spreads from head to TOE
Includes HANDS and FEET (vs. truncal rash in rubella)

Do not confuse with roseola (caused by HHV 6)

“Three C’s of Measles: Cough, coryza, conjuctivitis”

26
Q

Mumps virus

A

Also paramyxo

Parotitis, Orchitis and aseptic Meningitis (POM)
can cause sterility, especially after puberty.

27
Q

Rabies

A

Bullet shaped, Negri bodies
Commonly found in Purkinjee cells of cerebellum

Rabies have LONG incubation period (wks to months)

Postexposure treatment is wound cleansing and vaccination with rabies immune globulin

Travel to the CNS by retrograde fashion.

Progression of disease:
fever, malaise => agitation, photophobia, hydrophobia => paralysis, coma => death

More commonly from bat, raccoon, and skunk bites than from dog bites in the US.

28
Q

HEV

A
RNA hepevirus (no env, ss+linear icosahedral)
Fecal oral (like HA), esp with waterborne epidemics

No carriers, short incubation time
No HCC risk

High mortality in pregnant women

“enteric, expectant mother, and epidemic”

29
Q

Viral hepatitis

A

Episodes of fver, jaundice, elevated ALT and AST

HAV/HEV are oral fecal
HBV: use its own DNA dependent DNA pol to make full strand dsDNA. Then the host RNA polymerase transcribes them.

30
Q

Hepatitis markers

A

Anti HBc: antibody to HBcAg
= IgM=acute/recent infection, IgG=prior exposure or chronic infection.

HBeAg: a second different antigenic determinants in the HBV core. HBeAg indicates active viral replicaiton and thus high transmissibility

Anti HBe: antibody to E antigen, indicates low transmissiblity

Window period: no antigen, but anti HBe and anti HBc (IgM) and no anti HBs

Chronic with high infectivity: HBsAg, HBeAg and anti HBc (IgG), but no anti HBs

Chronic with low infectivity: HBsAg, anti HBe and anti HBc (IgG), but no anti HBs

31
Q

HIV

A

Diploid genome (RNA), three structural proteins.

Env (gp120, gp41): fromed from cleavage of gp160 to form enveloped proteins

  • gp120: attachment CD4 cells
  • gp41: fusion protein

Gag(p24): capsid protein
Pol: RT, aspartate protease, integrase

Virus binds CCR5 (early), or CXCR4 (late coreceptors and CD4 on T cells; it only binds to CCR5 and CD4 on macrophages.

32
Q

HIV diagnosis

A

ELISA: high sensitive, to rule out
Western: high specific, to rule in
PCR: viral load, to monitor drug efficacy

AID dx: <1.5

ELISA/Western: falsely negative in the first 2 months of HIV infectipn and falsely positive initially in babies born to infected mother (as anti gp120 crosses placental).

33
Q

HIV time course

A

Four stages
Flu like, feeling fine, falling count, final crisis

CD4 < 200: AIDS.

During the latent phase, the virus replicates in the LN