Unit 4 Viruses and Antiviral Medication Flashcards Preview

Disease and Defense Mine > Unit 4 Viruses and Antiviral Medication > Flashcards

Flashcards in Unit 4 Viruses and Antiviral Medication Deck (23):
1

respiratory syncytial virus (rsv)

-incubation: 3-5 days
-enveloped
-transmission: large droplets, invades conjuntiva and nasopharynx
-ss RNA neg
-causes lower resp. tract infection, esp. in young children
-tx: ribavirin, vaccine failed, prophylaxis with respigam or synagis

2

herpes simplex virus (hsv)

-incubation: 2-12 days, avg is 4
-dsDNA, enveloped
-transmission: skin to skin contact
-primary: may be silent, gingivostomatitis, herpatic whitlow, karatitis (eye), encephalitis
-can establish latency in neural ganglia
-reactivation of hsv 1 and 2 can be symptomatic or asymptomatic, but is most commonly asymptomatic
-reactivation can begin with tingling sensation followed by blister
-tx: acyclvir/valacyclovir/penciclovir, docosonol, gangcyclovir, c section for women with active lesions, no vaccine

3

varicella zoster virus (vzv)

-dsDNA, enveloped
-incubation: 10 - 21 days
-transmission: close contact or respiratory
-primary infection= chicken pox acute systemic infection
-can establish latency in neural ganglia- shingles
-tx: acyclovir at high dose, gancyclovir
-vaccine: live attenuated, do not give to pregnant or immunocomrompised pts

4

cytomegalovirus (cmv)

-dsDNA, enveloped
-incubation: 2 weeks to 2 months, asymptomatic in health people
-transmission: bodily fluids, birth
-can establish latency within monocytes and lymphocytes
-reactivation is associated with pneumonia, colitis, & retinitis
-tx: cidofavir, foscarnet, gancyclovir, no vaccine
-IgG present if had infection previously
-IgM present if current active infection

5

influenza virus

-neg ssRNA (8 pieces), enveloped, RdRp, H and N structure, A, B, C types
-incubation: 1-3 days
-transmission: enters mucus membranes, aerosolized droplets, respiratory
-it is safe to administer inactivated flu vaccine to pregnant pts
-tx: amantiadine/rimantadine, oseltamivir, zanamivir, peramivir

6

ebola virus

-enveloped neg ssRNA, VP40 budding structure, VP24 budding structure & defense, VP35= RdRp
-incubation: 2-21 days
-transmission: mucus membrane contact with an infected person
-severe infection associated with: diarrhea, 5-10L fluid loss/day, DIC
-tx: no approved tx, some in trials

7

pneumocystis jiroveci

-tx with pantamidine

8

acyclovir/vancyclovir/penciclovir

-MOA: phosphorylated by viral thymidine kinase- inhibits viral DNA
-pharmacokinetics: [A] topical, oral, IV (bioavailability greater in VAL/PEN, A=15-30%, VAL/PEN= 80%), P has renal excretion
-spectrum: HSV1*, HSV2* (and VZV* at higher doses)
-adverse: MINOR TOXICITIES (high levls with valacyclovir may inc. risk of CNS/renal side effects)
-preferentially targets viral DNA polymerase

9

palivizumab

-monoclonal antibody
-can be used to protect high risk infants from RSV

10

amantidine/rimantidine

-targets the viral uncoating stage of influenza life style
-spectrum: INFLUENZA A
-A*- eliminated renally
-R*- eliminated hepatically

11

docosanol (OTC)

-MOA: inhibits fusion between plasma membrane and HSV envelope
-pharmacokinetics: TOPICALLY applied 5x daily
-spectrum: HSV1 labialis
-adverse: well tolerated

12

ganciclovir/valganciclovir

-MOA: phosphrylated by viral thymidine kinase to active form that inhibits viral DNA polymerase
-pharmacokinetics: poor oral absorption (good with val), distributes to CNS, renal excretion
-spectrum: HSV, VXV, CMV, SIGHT-THREATENING CMV retinitis
-adverse: BONE MARROW DEPRESSION, CNS

13

cidofovir

-MOA: NUCLEOTIDE ANALOG, phosphorylated to active form by host kinases, inhibits viral DNA polymerase
-pharmacokinetics: long intracellular half life, given IV weekly/biweekly
-spectrum: many DNA viruses, CMV INFECTIONS (if resistant to ganciclovir/foscarnet)
-adverse: NEPHROTOXICITY (dec by probenecid use), rash in HIV pts

14

foscarnet

-MOA: pyrophosphate analog (NO ACTIVATION STEP), inhibits viral DNA/RNA polymerase and RT
-pharmacokinetics: poor oral bioavailability, requires continuous infusion
-spectrum: CMV INFECTIONS (Gan resistant), acyclovir resistant HSV infections, HIV (second line)
-adverse: RENAL IMPAIRMENT, severe n/v electrolyte imbalance (esp. HYPOCALCEMIA)

15

ribavirin

-MOA: triphosphorylated to active form, inhibits IMP dehydrogenase, inhibits viral RdRp, NUCLEOSIDE ANALOG
-pharmacokinetics: aerosol administration, well-absorbed ORALLY, long intracellular half life
-spectrum: RSV* (inh), hep C (oral) (w/ interferon)
-adverse: LOW AEROSOL TOXICITY, teratogen, systemic toxicity includes ANEMIA, bone marrow depression

16

HIV

-slow, progressive

17

cold/diarrhea viral outcome

-acute local

18

measles/smallpox viral outcome

-acute systemic

19

rubella in neonate viral outcome

-chronic/persistent

20

Herpes Virus Family

-HSV1
-HSV2
-VZV
-CMV

21

oseltamivir/zanamivir/peramivir

-spectrum: influenza A, B, C
-adverse: Z- (bronchospasm)

22

IgG vs IgM

IgG is memory, IgM is current infection

23

pentamadine

-treats pneumocytis jiroveci