Lecture 22

Question 1

What disease does herpes simplex type 1 virus 1 cause?

Answer 1

Cold Sores

Question 2

What disease does herpes simplex type 2 virus cause?

Answer 2

GenItial herpes

Question 3

What disease does varicella zoster virus cause?

Answer 3

Chicken pox and shingles

Question 4

What disease does Epstein-Barr Virus cause?

Answer 4

Glandular fever

Question 5

What disease does cytomegalovirus cause?

Answer 5

Minor illness

Question 6

What disease does human herpes virus 6 cause?

Answer 6

Roseola infantum

Question 7

What disease does human herpes virus 7 cause

Answer 7

minor illness

Question 8

What disease does human herpes virus 8 cause?

Answer 8

Kaposi’s Sarcoma

Question 9

What are the common features of herpes virus infections?

Answer 9

Uusally cause a minor illness
Have persistent latent infection with intermittent shedding
Is a lytic virus
Persistent infection of nerve cells, skin and lymphocytes

Question 10

What is tegument?

Answer 10

Gloop inside the envelope of the virus

Question 11

What is the structure of herpes viruses?

Answer 11

Enveloped virus with a nucleocapsid, envelope contains 80 viral proteins

Question 12

How are herpes viruses diagnosed?

Answer 12

Syndrome, immunofluorescence, culture, serology, PCR

Question 13

How are herpes simplex 1 and 2 treated?

Answer 13

Acyclovir or related drugs

Question 14

What are the features of herpes simplex type 1 virus?

Answer 14

Infection occurs via contaminated saliva
Replication of the virus occurs in the skin and oral mambranes
Latent infection occurs in trigeminal ganglion
Reactivation of the virus causes cold sores

Question 15

What causes neonatal herpes and what is its frequency?

Answer 15

1:5000 births
Timing is important as a recurrent shedding of the virus must occur during birth but there must be no antibodies yet present in the mother which could be transferred to the child
The young immune system of the child results in the virus being spread throughout the entire body

Question 16

How can herpes simplex virus 1 cause encephalitis or meningitis?

Answer 16

Instead of spreading down the axon, the herpes virus does the other way travelling towards the brain

Question 17

What are the features of varicella zoster virus?

Answer 17

Infection occurs through saliva or skin or coughing
Replication occurs in skin and mucous membranes
Latent infection occurs in the dorsal root ganglion
Reactivation causes shingles restricted to the dermatome of the latently infected neuron

Question 18

What are the features of the epstein-Barr virus?

Answer 18

Infection occurs via infected saliva (“Kissing Disease”)
Infection occurs in B lymphocytes in tonsils, allowing spread to other lymph nodes
Cytotoxic T lymphocytes attack the infected B lymphocytes causing illness

Question 19

What is glandular fever?

Answer 19

acute Epstein-Barr Virus infection
about 30 days is required as an incubation phase as the T lymphocytes must first recognise and mount an immune response
Sore throats, swollen tonsils and enlarged, tender lymph nodes occur
Typically lethargy and anorexia occur

Question 20

What is the effect of EBV infection on B lymphocytes?

Answer 20

They become continually activated, constantly secreting virus and antibodies
Inadequate killing of these cells can cause B cell lymphoma

Question 21

How is EBV infection diagnosed?

Answer 21

Test for presence of antibodies (sheep red blood cells can be used here as the antibody against EBV also reacts against them)
Specific EBV antibodies can be tested
EBV DNA can be detected
Detection of abnormal activated cytotoxic T cells