Micro - Virology (Overview of DNA Viruses)

Question 1

What are the 7 examples of DNA viruses?

Answer 1

(1) Herpesviruses (2) Hepadnavirus (3) Adenovirus (4) Parvovirus (5) Papillomavirus (6) Polyomavirus (7) Poxvirus

Question 2

Do herpesviruses have envelopes? What is their DNA structure?

Answer 2

Yes; DS and linear

Question 3

Does Hepadnavirus have an envelope? What is its DNA structure?

Answer 3

Yes; Partially DS and circular

Question 4

Does Adenovirus have an envelope? What is its DNA structure?

Answer 4

No; DS & linear

Question 5

Does Parvovirus have an envelope? What is its DNA structure?

Answer 5

No; SS & linear (-) (Note: Smallest DNA virus)

Question 6

Does Papillomavirus have an envelope? What is its DNA structure?

Answer 6

No; DS & circular

Question 7

Does Polyomavirus have an envelope? What is its DNA structure?

Answer 7

No; DS & circular

Question 8

Does Poxvirus have an envelope? What is its DNA structure?

Answer 8

Yes; DS & linear (Note: Largest DNA virus)

Question 9

What is the smallest DNA virus? What is the largest DNA virus?

Answer 9

Parvovirus; Poxvirus

Question 10

What are the 3 DNA viruses that have envelopes?

Answer 10

(1) Herpes virus (2) Hepadnavirus (3) Poxvirus

Question 11

Name at least 5 Herpesviruses representative of the several kinds of Herpesviruses.

Answer 11

(1) HSV-1 or HSV-2 (2) VZV (HHV-3) (3) EBV (HHV-4) (4) CMV (HHV-5) (5) HHV-6, HHV-7, or HHV-8

Question 12

What is the medical importance of HSV-1? What about HSV-2?

Answer 12

HSV-1: Oral (and some genital) lesions, spontaneous temporal lobe encephalitis, keratoconjuctivitis; HSV-2: Genital (and some oral) lesions

Question 13

What is another name for VZV? What is its medical importance?

Answer 13

Varicella zoster virus = HHV-3; Chickenpox, zoster (shingles), vaccine available

Question 14

What is another name for EBV? What is its medical importance?

Answer 14

Epstein-Barr virus = HHV-4; Mononucleosis, Burkitt’s lymphoma, Hodgkin’s lymphoma

Question 15

What is another name for CMV? What is its medical importance?

Answer 15

Cytomegalovirus = HHV-5; Infection in immunosuppressed patients (AIDS retinitis), especially transplant recipients, congenital defects (“sightomegalovirus”)

Question 16

What is the medical importance of HHV-6?

Answer 16

Roseola (exanthem subitum)

Question 17

What is the medical importance of HHV-7?

Answer 17

Less common cause of roseola (than HHV-6)

Question 18

What is the medical importance of HHV-8?

Answer 18

Kaposi’s sarcoma-associated herpesvirus (KSHV)

Question 19

For which of the herpesviruses is a vaccine available? What is its medical importance?

Answer 19

VZV/HHV-3; Chickenpox, zoster (shingles)

Question 20

What condition(s) does HBV cause?

Answer 20

Acute or chronic hepatitis

Question 21

What is contained in the HBV vaccine?

Answer 21

Contains HBV surface antigen

Question 22

Which DNA virus has reverse transcriptase (although it is not a retrovirus)?

Answer 22

HBV

Question 23

What 4 condition(s) does Adenovirus cause?

Answer 23

(1) Febrile pharyngitis - sore throat (2) Acute hemorrhagic cystitis (3) Pneumonia (4) Conjunctivitis - “pink eye”

Question 24

What are the 5 medically important associations to make with Parvovirus?

Answer 24

(1) B19 virus - aplastic crisis in sickle cell disease (2) “Slapped cheeks” rash in children - erythema infectiosum (Fifth disease) (3) RBC destruction in fetus leads to hydrops fetalis and death (4) Pure RBC aplasia (5) Rheumatoid-arthritis-like syndrome in adults

Question 25

Which DNA virus is associated with aplastic crisis in sickle cell disease patients?

Answer 25

Parvovirus B19

Question 26

What is another name for Fifth disease? How does it present? What kind of DNA virus causes it?

Answer 26

Erythema Infectiosum; "Slapped cheeks" rash in children; Parvovirus

Question 27

Which kind of DNA virus can cause death in fetuses? What is the mechanism behind this?

Answer 27

Parvovirus; RBC destruction in fetus leads to hydrops fetalis and death

Question 28

With what kind of anemia is Parvovirus associated?

Answer 28

Pure RBC aplasia

Question 29

What 2 symptoms/conditions may Parovirus cause in adults?

Answer 29

Pure RBC aplasia and Rheumatoid-arthritis-like syndrome in adults

Question 30

What 3 condition(s) does Papillomavirus cause?

Answer 30

Warts (1, 2, 6, 11), CIN, Cervical cancer (16, 18)

Question 31

Which types of HPV cause warts?

Answer 31

1, 2, 6, 11

Question 32

Which types of HPV cause cervical cancer?

Answer 32

16, 18

Question 33

Is their a vaccine for HPV? If so, what kind?

Answer 33

Cervical cancer (16, 18) vaccine availble

Question 34

What are examples of Polyomaviruses?

Answer 34

(1) JC virus (2) BK virus

Question 35

Again, what are the Polyomaviruses? With what condition(s) is each associated?

Answer 35

(1) JC virus - progressive multifocal leukoencephalopathy (PML) in HIV (2) BK virus - transplant patients, commonly targets kidneys; Think: "JC: Junky Cerebrum, BK: Bad Kidney"

Question 36

What are 3 medically important associations to make with Poxvirus?

Answer 36

(1) Smallpox, although eradicated, could be used in germ warfare (2) Cowpox ("milkmaid's blisters) (3) Molluscum contagiosum - flesh-colored dome lesions with central dimple