HIV/AIDS

Question 1

What causes HIV?

Answer 1

Human immunodeficiency virus

Question 2

What does HIV do to the immune system?

Answer 2

The HIV spike protein interacts with the CD4 protein on helper T lymphocytes, hijacking their cell machinery to replicate.

Blood virus level rises until killer T cells recognise and start killing infected helper T cells faster than bone marrow can replenish them, decreasing helper T lymphocyte levels.

Question 3

Are HIV infected helper T lymphocytes always producing HIV proteins?

Answer 3

No, which is why HIV can lie undetected by the immune system in certain dormant infected cells as it won’t be presented on HLA molecules

Question 4

What can HIV infection lead to?

What does this mean for the patient?

Answer 4

Acquired Immune Deficiency Syndrome (AIDS) due to decreased helper T lymphocytes in blood.

The patient is more susceptible to infections usually easily dealt with by a healthy immune system.

Question 5

How is HIV transmitted?

Answer 5

Contact with blood and genital secretions

Question 6

What tests can be used to diagnose HIV?

Answer 6

Blood tests for HIV antibodies 4-6 weeks after most recent exposure

Question 7

What is the current treatment for HIV?

Answer 7

No cure, but anti-retroviral drugs (Atripla) prevents viral replication and reduce HIV present in blood and allows recovery of helper T lymphocyte population

Undetectable = untransmissable

Question 8

What are some preventative measures for HIV?

Answer 8

Preventing exposure to bodily fluids
- Reduction of sexual partners
- Usage of condoms

Pre-exposure prophylaxis for individuals at higher risk of infection