4 Antivirals

Question 1

What is antigenic drift?

Answer 1

Some antigens may become mutated during reproduction keeping prevent the immune system from recognizing the virus. (passively evading detection)

Question 2

What is antigenic shift?

Answer 2

A large change in the expression of surface antigens on a virus to evade the host immune system. (actively evading detection)

Question 3

Does antigen drift or shift cause epidemics?

Answer 3

Antigenic shift

Question 4

What are the four target sites of action of antivirals?

Answer 4

Inhibition of 1) DNA Polymerase, 2) M2 protein, 3) RNA Polymerase, 4) Neuraminidase

Question 5

What antiviral drugs target DNA polymerase?

Answer 5

Famcyclovir, Acyclovir, Penicyclovir, Valacyclovir, Ganciclovir, and Foscarnet (FAPVGF)

Question 6

What does Amantadine target in the virus?

Answer 6

M2 protein which aids in the uncoating of the virus.

Question 7

What does Ribavarin target?

Answer 7

RNA polymerase to prevent translation of viral proteins

Question 8

What two antiviral drugs target neuraminidase?

Answer 8

Oseltamivir and Zanamivir (OZ)

Question 9

Where does HSV-2 tend to reside during remission?

Answer 9

In the Sacral Ganglia at the base of the spine

Question 10

What virus causes chickenpox and shingles?

Answer 10

varicella zoster virus (VZV)

Question 11

When is chicken pox contagious?

Answer 11

1-2 days PRIOR to having a rash

Question 12

Define immunosenescence

Answer 12

age-related decline in immune function

that increases risk of infection

Question 13

Where do canker sores appear vs. cold sores?

Answer 13

• canker sores appear in the mouth and on the gingiva

- cold sores are outside the mouth, on the lips, etc

Question 14

Are canker sores contagious?

Answer 14

No

Question 15

What are three go-to drugs to treat HSV and VZV?

Answer 15

Acyclovir primarily for HSV, Valacyclovir for both, and Famciclovir for VZV

Question 16

Why do patients taking antivirals for HSV or VZV need to drink plenty of water?

Answer 16

They can cause crystalline nephropathy by accumulating in the kidneys

Question 17

What drug is approved for prophylaxis and treatment of Cytomegalo virus?

Answer 17

Gancyclovir

Question 18

What drug inhibits spermatogenesis and shouldn’t be prescribed to pregnant patients or pts that want to have kids?

Answer 18

Gancyclovir

Question 19

If the HSV or CMV infection is resistant to acyclovir or gancyclovir, what do you prescribe?

Answer 19

Foscarnet

Question 20

What drug is used topically to treat HSV sores?

Answer 20

Peniciclovir

Question 21

How exactly does Acyclovir work?

Answer 21

It undergoes 3 phosphorylations before inserting into the viral DNA where it blocks elongation

Question 22

_________ is 10x more potent against HSV-1 and HSV-2 than against VZV.

Answer 22

Acyclovir

Question 23

Why can Foscarnet work on viruses that are resistant to acyclovir and gancyclovir?

Answer 23

Because it doesn’t require viral kinases to be activated

Question 24

What drug would you use to treat Influenza A and B viruses?

Answer 24

Oseltamivir (Tamiflu)

Question 25

What happens to the course of infection of Tamiflue isn’t given within the first 24-72 hours?

Answer 25

It increases the time of sickness by 1-2 days

Question 26

What drug is used to treat and prophylaxis of Influenza A and B viruses?

Answer 26

Zanamivir

Question 27

What are contraindications for using Zanamivir?

Answer 27

severe asthma, COPD, or allergies to mile proteins

Question 28

What are contraindication for prescribing Amantadine?

Answer 28

Renal impairment, epilepsy, closed angle glaucoma, and pregnant pts

Question 29

What has a near 100% resistance to Amantadine?

Answer 29

Influenza B virus

Question 30

Can you use Amantadine for Influenza A infections?

Answer 30

yes, but not with Influenze