III - A. Virology | 24. Retroviruses and AIDS

Question 1

I. Retroviruses
1. What are the features of Retroviruses?

Answer 1

Question 2

I. Retroviruses
2. What is the replication mechanism of Retroviruses?

Answer 2

• It integrates into the DNA of the host cell
• Direction of nucleic acid transcription is REVERSED : RNA → DNA

Question 3

I. Retroviruses
3. What are the 2 examples of Retroviruses?

Answer 3

• HIV: Human immunodeficiency virus
• HTLV 1 and 2: human T-cell lymphotropic / leukemia virus

Question 4

II. HIV - Human immunodeficiency virus
1. What is the pathomechanism of HIV?

Answer 4

Question 5

II. HIV - Human immunodeficiency virus
2. What is the transmission of HIV?

Answer 5

1. SEXUAL transmission
2. PARENTERAL – WITH BLOOD
3. VERTICAL (mother to child)

(NO SPREAD by saliva, swimming pool, contact Lower chances of transmission if viral load is low !
– treatment!)

Question 6

II. HIV - Human immunodeficiency virus
3. What is SEXUAL transmission of HIV?

Answer 6

• male to male > male to female > female to male
• Way of transmission for 75% of infections

(NO SPREAD by saliva, swimming pool, contact Lower chances of transmission if viral load is low !
– treatment!)

Question 7

II. HIV - Human immunodeficiency virus
4. What is PARENTERAL – WITH BLOOD transmission of HIV?

Answer 7

• Blood transfusion & other blood products – screening!
• Needle stick
  +) IV drug abusers, tattoo, health care needle accidents
• Health care workers, other than needle => open wound, broken mucous membrane – very rare

(NO SPREAD by saliva, swimming pool, contact Lower chances of transmission if viral load is low !
– treatment!)

Question 8

II. HIV - Human immunodeficiency virus
5. What is VERTICAL transmission of HIV?

Answer 8

Intrauterine + Perinatal + Breast feeding

(NO SPREAD by saliva, swimming pool, contact Lower chances of transmission if viral load is low !
– treatment!)

Question 9

II. HIV - Human immunodeficiency virus
6. What is the HIV virus structure?

Answer 9

Icosahedral, enveloped virus

Question 10

II. HIV - Human immunodeficiency virus - PATHOMECHANISM OF INFECTION
7A. What are 7 steps of PATHOMECHANISM OF INFECTION?

Answer 10

1. Binding
2. DNA copy of virus RNA is made by reverse transciptase
3. Integrates into host DNA genome in nucleus
4. Synthesis (mRNA and polyprotein)
5. Cleavage of polyprotein into functional proteins
6. Assembly of new viral particles
7. Release (by exocytosis) – lysis of the cell

Question 11

II. HIV - Human immunodeficiency virus - PATHOMECHANISM OF INFECTION
7B. What happen in 1st step: BINDING of PATHOMECHANISM OF HIV INFECTION?

Answer 11

Question 12

II. HIV - Human immunodeficiency virus
8A1. What are the features of disease caused by HIV - Human immunodeficiency virus?

Answer 12

(bonus) 2 stages
1. Stage: ACUTE RETROVIRAL SYNDROME (ARS)
2. stage: CHRONIC PHASE
3. AIDS: ACQUIRED IMMUNODEFICIENCY SYNDROME

Question 13

II. HIV - Human immunodeficiency virus
8A2. What are the 3 stages of HIV - Human immunodeficiency virus?

Answer 13

1. Stage: ACUTE RETROVIRAL SYNDROME (ARS)
2. stage: CHRONIC PHASE
3. AIDS: ACQUIRED IMMUNODEFICIENCY SYNDROME

Question 14

II. HIV - Human immunodeficiency virus
8B. What happen in 1. Stage: ACUTE RETROVIRAL SYNDROME (ARS)? (clinical disease caused by HIV)

Answer 14

Question 15

II. HIV - Human immunodeficiency virus
8C. What happen in 2. stage: CHRONIC PHASE? (clinical disease caused by HIV)

Answer 15

Question 16

II. HIV - Human immunodeficiency virus
8D. What happen in 3. AIDS: ACQUIRED IMMUNODEFICIENCY SYNDROME? (clinical disease caused by HIV)

Answer 16

Question 17

II. HIV - Human immunodeficiency virus
9A. What are the 4 types of opportunistic infections in AIDS?

Answer 17

1. Bacterial
2. Fungal
3. Parasitic
4. Viral

Question 18

II. HIV - Human immunodeficiency virus
9B. What is an example of bacterial opportunistic infections in AIDS?

Answer 18

eg. Reactivation of latent tuberculosis – Mycobacterium tuberculosis

Question 19

II. HIV - Human immunodeficiency virus
9C. What is an example of fungal opportunistic infections in AIDS?

Answer 19

eg. Candidiasis – more severe, widespread compared to healthy people
-> Oral – thrush / Candida oesophagitis / generalised infection

Question 20

II. HIV - Human immunodeficiency virus
9D. What is an example of parasitic opportunistic infections in AIDS?

Answer 20

eg. Toxoplasma

Question 21

II. HIV - Human immunodeficiency virus
9E. What are viral opportunistic infections in AIDS?

Answer 21

• Disseminated HSV , esophagitis
• EBV: oral hairy leukoplakia (OHL) of the tongue, seen mostly in immunosupressed patients
• HHV8: Kaposi sarcoma (KS)
• HPV associated oropharyngeal cancer

Question 22

II. HIV - Human immunodeficiency virus - viral opportunistic infections in AIDS
9F. What are the features of HHV8: Kaposi sarcoma (KS)?

Answer 22

Question 23

II. HIV - Human immunodeficiency virus - viral opportunistic infections in AIDS
9G. What are the features of HPV associated oropharyngeal cancer?

Answer 23

Question 24

II. HIV - Human immunodeficiency virus
10. What is the diagnosis of HIV Infection?

Answer 24

Question 25

II. HIV - Human immunodeficiency virus
11. What is the confirmation of HIV INFECTION?

Answer 25

Question 26

II. HIV - Human immunodeficiency virus
12. What is the treatment of HIV infection?

Answer 26

Question 27

II. HIV - Human immunodeficiency virus
13A. What are general measures of prevention of HIV infection?

Answer 27

Question 28

II. HIV - Human immunodeficiency virus
13B. What are general measures for prevention of HIV infection?

Answer 28

Question 29

II. HIV - Human immunodeficiency virus
13C. What is PreP (pre-exposure prophylaxis) for prevention of HIV infection?

Answer 29

Question 30

II. HIV - Human immunodeficiency virus
13D. What is vaccination for prevention of HIV infection?

Answer 30

• Currently not available, trials,
• eg. based on viral vector containing genetically engineered versions of three HIV genes (env, gag and pol)

Question 31

III. What are the features of HTLV-I?

Answer 31

I