III - A. Virology | 11. Herpesviruses (EBV, CMV, HHV6, HHV7, HHV8)

Question 1

I. Basics
1. List beta-herpesviruses and gamma-herpesviruses

Answer 1

• betaherpesviruses: CMV, HHV6, HHV7
• gammaherpesviruses: EBV, HHV8

Question 2

II. CMV and EBV
1. What are the genetic material and morphology of CMV and EBV?

Answer 2

• dsDNA genome
• icosahedral capsid
• enveloped viruses

Question 3

II. CMV & EBV - CMV
2A. What are the features of Cytomegalovirus (CMV, HHV5)

Answer 3

• leads to cytopathic effects in infected cells
• infected cells do not lyse, viral production is continous
• inflammation and tissue damage in affected organs

Question 4

II. CMV & EBV - CMV
2B. What is the source of infection of Cytomegalovirus (CMV, HHV5)

Answer 4

nfected individual (latency!)

Question 5

II. CMV & EBV - CMV
2C. What is the route of transmission of Cytomegalovirus (CMV, HHV5)

Answer 5

• saliva, genital mucous, blood, breast milk
• transplacentar transmission!

Question 6

II. CMV & EBV - CMV
2D. What is the pathomechanism of Cytomegalovirus (CMV, HHV5)

Answer 6

Infects exocrine glands, renal tubules, monocytes and endothelial cells

Question 7

II. CMV & EBV - CMV
2E. What are the diseases caused by Cytomegalovirus (CMV, HHV5)?

Answer 7

• often asymptomatic in healthy individuals
• can cause mononucleosis
• pneumonitis, chorioretinitis, encephalitis in immunosuppressed
• congenital / perinatal infection may lead to mental retardation, periventricular calcification, chorioretinitis, deafness, pneumonitis, hepatitis

Question 8

II. CMV & EBV - CMV
2F. What are the diagnosis for Cytomegalovirus (CMV, HHV5)?

Answer 8

blood sample
- serology (detection of IgM)
- PCR

Question 9

II. CMV & EBV - CMV
2G. What are the therapy and prevention for Cytomegalovirus (CMV, HHV5)?

Answer 9

• gancyclovir, cidofovir, foscarnet
• screning of donated organs and blood (serological status)

Question 10

II. CMV & EBV - EBV
3A. What are the features of Ebstein-Barr virus (EBV, HHV4)?

Answer 10

• causes cytopathic effects in infected cells
• may transform infected cells (leads to cancer)

Question 11

II. CMV & EBV - EBV
3B. What is the source of infection of Ebstein-Barr virus (EBV, HHV4)?

Answer 11

Infected individual (latency!)

Question 12

II. CMV & EBV - EBV
3C. What is the ROUTE of infection of Ebstein-Barr virus (EBV, HHV4)?

Answer 12

mainly througH saliva (continous virus production even during latency!)

Question 13

II. CMV & EBV - EBV
3D. What is the pathomechanism of Ebstein-Barr virus (EBV, HHV4)?

Answer 13

• infects mucous membranes and CD21 positive B-lymphocytes
• viral proteins may lead to the immortalisation of B-cells
  (may lead to cancer!)

Question 14

II. CMV & EBV - EBV
3E. What are the diseases caused by Ebstein-Barr virus (EBV, HHV4)?

Answer 14

Question 15

II. CMV & EBV - EBV
3F. What re the features of mononucleosis infectiosa (glandular fever) caused by EBV?

Answer 15

• the virus replicates in the oropharynx and parotid gland
• 30-50 days long incubation period, then fever, sore throat, splenomegaly, lymphocytosis

Question 16

II. CMV & EBV - EBV
3G. What is the diagnosis of EBV?

Answer 16

1. based on clinical signs and symptoms
2. serological tests may be useful
   - Paul-Bunnel reaaction (+ plasma agglutinates sheep RBCs)
   - detection of viral proteins with ELISA (EBNA, VCA)

Question 17

II. CMV & EBV - EBV
3H. What is the therapy for EBV?

Answer 17

acyclovir

Question 18

II. CMV & EBV - EBV
3I. What is „accidental diagnosis” by EBV?

Answer 18

in acute EBV infection the administration of beta-lactam antibiotics (especially aminopenicillins) may lead to a generalised rash
=> „ampicillin rash”

Question 19

III. HHV6, HHV7 and HHV8
1. What are the genetic material and morphology of HHV6 & HHV7

Answer 19

• dsDNA genome
• icosahedral capsid
• enveloped viruses

Question 21

III. HHV6, HHV7 and HHV8 - HH6
2A. What are the features of HH6?

Answer 21

It has two distinct subtypes (HHV6A, HHV6B)

Question 21

III. HHV6, HHV7 and HHV8 - HH6
2B. What is the source of infection of HH6?

Answer 21

infected individual

Question 22

III. HHV6, HHV7 and HHV8 - HH6
2C. What is the route of transmission of HH6?

Answer 22

probably through saliva

Question 23

III. HHV6, HHV7 and HHV8 - HH6
2D. What is the pathomechanism of HH6?

Answer 23

infects T-cells

Question 24

III. HHV6, HHV7 and HHV8 - HH6
2E. What is the disease caused by HH6?

Answer 24

• HHV6B leads to roseola infantum in children
• HHV6A does not cause an acute infection, but in immunosuppressed patients it can reactivate from its latency and lead to encephalitis, chorioretinitis, pneumonitis

Question 25

III. HHV6, HHV7 and HHV8 - HH7
3A. What are the features of HH7?

Answer 25

• quite similar to HHV6
• majority of the population older then 3 years old is seropositive after

Question 26

III. HHV6, HHV7 and HHV8 - HH7
3B. What is the source of infection of HH7?

Answer 26

infected individual

Question 27

III. HHV6, HHV7 and HHV8 - HH7
3C. What is the route of transmission of HH7?

Answer 27

probably through saliva

Question 28

III. HHV6, HHV7 and HHV8 - HH7
3D. What is the pathomechamism of HH7?

Answer 28

infects T-cells

Question 29

III. HHV6, HHV7 and HHV8 - HH7
3E. What is the disease caused by HH7?

Answer 29

roseola infantum

Question 30

III. HHV6, HHV7 and HHV8 - HHV8
4A. What are the features of HHV8?

Answer 30

• Kaposi’s sarcoma vírus (KHSV)
• leads to transsformation (leads to cancer)
• primary infection is often asymptomatic

Question 31

III. HHV6, HHV7 and HHV8 - HHV8
4B. What is the source of infection of HHV8?

Answer 31

infected individual

Question 32

III. HHV6, HHV7 and HHV8 - HHV8
4C. What is the route of transmission of HHV8?

Answer 32

• Through direct contact
• sexually transmitted

Question 33

III. HHV6, HHV7 and HHV8 - HHV8
4D. What is of pathomechanism of HHV8?

Answer 33

probably infects B-lymphocytes and other cells

Question 34

III. HHV6, HHV7 and HHV8 - HHV8
4E. What are the diseases caused by HHV8?

Answer 34

Kaposi’ sarcoma (vessel proliferation)
=> INDEX disease!

Question 35

III. HHV6, HHV7 and HHV8 - HHV8
4F. What are the diagnosis for HHV8?

Answer 35

• serology
• PCR