III - A. Virology | 12. Papilloma and Parvoviruses

Question 1

I. Parvoviruses
1. What are the genetic material and morphology of parvoviruses?

Answer 1

1. Genetic material
   - ssDNA genome!!! (either + or - ssDNA)
2. Morphology:
   - icosahedral capsid
   - replicate inside host cell’s nucleus

Question 2

I. Parvoviruses
2. What are the 3 human pathogens?

Answer 2

3 human pathogenes: parvovirus B19, a human bocavirus and adenoassociated viruses

Question 3

I. Parvoviruses - Parvovirus B19
3. What is the source of infection of Parvovirus B19?

Answer 3

infected individual

Question 4

I. Parvoviruses - Parvovirus B19
4. What is the route of transmission of Parvovirus B19?

Answer 4

• through respiratory droplets
• blood transfusion

Question 5

I. Parvoviruses - Parvovirus B19
5. What is the pathomechanism of Parvovirus B19?

Answer 5

Infects RBC progenitors (proerythroblasts)

Question 6

I. Parvoviruses - Parvovirus B19
6. What are the diseases & symptoms Parvovirus B19?

Answer 6

1. Erythema infectiosum (5th disease)
   - bone marrow destruction, anaemia, aplastic crisis
   - immunocomplex production (slapped face), joint
   pain
2. Hydrops foetalis (if infection occures during pregnancy)

Question 7

I. Parvoviruses - Parvovirus B19
7. What is the diagnosis for disease caused by Parvovirus B19?

Answer 7

• based on symptoms
• antigen or genetic material (PCR) detection from blood

Question 8

I. Parvoviruses - Parvovirus B19
8. What is the therapy for disease caused by Parvovirus B19?

Answer 8

• supportive treatment
• transfusion
• anti-parvovirus B19 immunoglobulin

Question 9

II. Human papillomaviruses
1. What are the genetic material and morphology of Human papillomaviruses?

Answer 9

• dsDNA genome
• icosahedral capsid

Question 10

II. Human papillomaviruses
2. What is the main feature of Human papillomaviruses?

Answer 10

many different genotypes, with different outcomes

Question 11

II. Human papillomaviruses
3. What is the source of infection of Human papillomaviruses?

Answer 11

infected individual (even asymptomatic ones!)

Question 12

II. Human papillomaviruses
4. What is the route of transmission of Human papillomaviruses?

Answer 12

• through direct contact
• sexually transmitted

Question 13

II. Human papillomaviruses
5. What is the pathomechanism of Human papillomaviruses?

Answer 13

• Infect the basal cells of stratified epithelium
• Early proteins activate the host’s cell cycle through inhibition of the retinoblastoma (E7 protein) and switch off apoptosis (E6 protein)
• Needed for their replication (DNA polymerase is only present in replicating cells!)
• Induce cell proliferation ➡ warts
• Due to the slow proliferation and the skin localisation the immune response is mild and develops slowly

Question 14

II. Human papillomaviruses
6A. What are the diseases caused by Human papillomaviruses?

Answer 14

mucosotropic and cutaneous genotypes

Question 15

II. Human papillomaviruses
6B. What are the symptoms of cutaneous genotypes ?

Answer 15

cutaneous genotypes (for e.g. HPV1) may stay asymptomatic, or they can cause warts (verruca vulgaris, verruca plana)

Question 16

II. Human papillomaviruses
6C. What are the symptoms of mucosotropic genotypes ?

Answer 16

Mucosotropic genotypes can be subdivided into low risk and high risk viruses
1. Low risk: HPV6, HPV11
- LSIL, or condyloma acuminatum (genital wart)
2. High risk: HPV16, HPV18
- HSIL, cervix- and anorectalis cancer, or squamous cell cancer (skin, tongue, larynx)

Question 17

II. Human papillomaviruses
7. What is the diagnosis for Human papillomaviruses?

Answer 17

• aided visual inspection with acetic acid
• sampling with Citobrush of the infected area
• ## meaning of a positive result from a sampling without symptoms is controversial
• PCR
• based on the examination of a cervical smear we can estimate the level of transformation (Bethesda classification)

Question 18

II. Human papillomaviruses
8. What is the therapy for Human papillomaviruses?

Answer 18

Question 19

II. Human papillomaviruses
9A. What is the prevention for Human papillomaviruses

Answer 19

Question 20

II. Human papillomaviruses
9B. What are the feature of vaccines for Human papillomaviruses?

Answer 20

• The HPV vaccines can prevent the most common types of infection.
• recommended before the start of sexual activity, for both sexes!
• 2, 4 and 9-valent formulas

Question 21

II. Human papillomaviruses
9C. Why is screening Human papillomaviruses important ?

Answer 21

• screening is important, so we can detect the disease in the pre- cancerous stage (cervical screening: recommended on a yearly basis!)
• it takes 10 to 20 years to develop a cancer due to a HPV infection!