HIV/AIDS Johns Flashcards
What is HIV and how was it discovered?
- Etiologic agent of Acquired Immunodeficiency Syndrome (AIDS)
- Discovered independently by Luc Montagnier of France and Robert Gallo of the US In 1983-84
What are other former names of HIV?
- Human T cel lymphotrophic virus (HTLV-III)
- Lymphadenopathy associated virus (LAV)
- AIDS associated retrovirus (ARV)
How was HIV-2 discovered?
It was discovered in 1986 as an antigenic ally distinct virus endemic in West Africa
How does Viral Replication happen in HIV?
- First step, HIV attaches to susceptible host cell.
- Site of attachment is the CD4 antigen found on a variety of cells:
- –Helper T cells
- –Macrophages
- –Monocytes
- –B cells
- –Microglial brain cells
- –Intestinal cells
- T cells infected later on - After a period of latency lasting up to 10 years, viral replication is triggered and occurs at high rate
- CD4 cell may be destroyed in the process
- Destruction of large numbers of CD4 cause symptoms of HIV to appear
About how long can HIV be latent?
10 years
How is the HIV virus transmitted?
- Sexual transmission, presence of STD increases likelihood of transmission
- Exposure to infected blood or blood products
- Use of contaminated clotting factors by hemophiliacs
- Sharing of contaminated needles (IV drug users)
- Transplantation of infected tissues or organs
- Mother to fetus, perinatal transmission variable, dependent on viral load and mother’s CD4 count
What are the symptoms of Primary HIV Syndrome?
Mononucleosis-like, cold or flu-like symptoms may occur 6 to 12 weeks after infection
- lymphadenopathy
- fever
- rash
- headache
- fatigue
- diarrhea
- sore throat
- neurological manifestations
- no symptoms may be present
What is Primary HIV Syndrome like?
- Symptoms are relatively nonspecific
- HIV antibody tests often negative but becomes positive within 3 to 6 months, this process is known as seroconversion
- Large amount of HIV in the peripheral blood
- Primary HIV can be diagnosed using viral load titer assay or other tests
- Primary HIV syndrome resolves itself and HIV infected person remains asymptomatic for a prolonged period of time, often years.
How long is the ‘window’ period of HIV-1 infection?
About three weeks after primary infection.
When do the primary symptoms appear for HIV-1 infection?
Weeks 2-5
When do the secondary symptoms appear for HIV-1 infection?
Years 6-8
When does the HIV-1 p24 antigen spike?
Between weeks 3-4
When is the HIV viral load spike? Where does it decrease? Where does it increase?
Spike: Between weeks 3-4
Decreases: Week 4-Year 2
Increases: Year 2-10 (forever)
Where do HIV antibodies peak?
Around week 5-6, then they slowly decline over many years
When does HIV proviral DNA get really high?
Around week 3 and it stays around the same level for the rest of the disease
What happens during the Clinical Latency Period?
- HIV continues to reproduce, CD4 count Gradually declines from its normal value of 500-1200
- Once CD4 count drops below 500, HIV infected person at risk for opportunistic infections!!
What diseases are predictive the progression to AIDS?
- Persistent herpes-zoster infections (shingles)
- Oral candidiasis (thrush) - a lot of white in back of throat
- Oral hairy leukoplakia
- Kaposi’s sarcoma (KS)
Why do those with HIV get Oral Hairy Leukoplakia?
Being that HIV reduces immunologic activity, the intraoral environment is a prime target for chronic secondary infections and inflammatory processes, including OHL, which is due to the Epstein-Barr virus under immunosuppressed conditions
