Card Set Information

2011-05-08 23:10:29
hiv aids

Show Answers:

  1. Stages
    • 1. PRODOMAL stage: fever, headache, rash, diarrhea & drop in CD4
    • 2. LATENCY period: no symptoms
    • 3. Persistant generalized lymphadenopathy: Swollen lymph nodes, recurrent fevers, night sweats, extreme fatigue, cough, diarrhea. Opportunistic infections set in.
    • 4. full blown AIDS: Suffers from infection after infection, death occurs
  2. 1) Symptoms, epidemiology pathogenesis, prevention and treatment
    • Symptoms: No symptoms, or flu-like symptoms, an asymptomatic period, typically lasting 10yrs, symptoms of lung, brain, skin infections and then cancers.
    • Epidemiology: Present in blood, semen & vaginal secretions. Spread from unsafe sex, unsanitary needle usage or blood transfusions, transfers from mother-child.
    • Pathogeneis: Virus infects CD4+ lymphocytes(T-cells) & macrophages, therefore destroying the immune system’s ability to fight infection. (autocatalysis: When you have infection, these lymphocytes proliferate, causing more HIV to be expressed, which in tern causes more t-cells to be produced as they are trained to fight infection…the results is a massive amount of virus!)
Prevention/Treatment: Prevention due to safe sex practices. Treatment involves PROTEASE inhibitors, RT inhibitors, AIDS cocktail (during 1st stage). NO VACCINE available
  3. 2) HIV/AIDS: What type of virus causes AIDS?
    • Retrovirus, part of a subgroup of retroviruses called lentiviruses (slow viruses) that slowly cause infection.
    • Viruses are spherical, ENVELOPED, w/ 2 ss of RNA
  4. 3) How can you prove that HIV causes AIDS?
    • HIV fulfills Koch’s postulate.
    • Both linked in time, place & population.
    • Almost all ppl w/AIDS have Abs for HIV
    • LOW CD4 T-cell count is rare in ABSENSE of HIV infection
    • Severe immunosuppresion and AIDS illness are almost exclusively in HIV infected ppl
  5. 4) What is Reverse Transcriptase?
    An enzyme that aids RNA into being reverse transcribed into DNA. This enzyme is carried in the virus, as the host cells do not contain this enzyme naturally.
  6. 5) Symptoms and treatment of AIDS
    Symptoms related to HIV infection and continuing with opportunistic infections which can continue as you are immunosuppressed when you have AIDS. Treatment involves PROTEASE inhibitors, RT inhibitors, AIDS cocktail (during 1st stage). NO VACCINE available
  7. 6) Characteristics of HIV, its genome, capsid and envelope structure
    Spherical, contains 2 ss RNAs, each with Reverse transcriptase. Proteins embedded in envelope. Envelope made from human cell membrane. CAPSID is Bullet shaped WITHIN the envelope, made of viral proteins.
  8. 7) What type of cells does HIV attack
    Attacks T-cells and Macrophages (both are CD4+), CD4 is the main receptor for HIV.
  9. 8) AIDS treatment and prevention
    Prevention due to safe sex practices, safe injections & transfusions. Treatment involves PROTEASE inhibitors, RT inhibitors, AIDS cocktail (during 1st stage). NO VACCINE available
  10. 9)Factors affecting the latency period of HIV
    2-15 years. Normal CD4 count due to immune system fighting off virus. Antibodies to HIV are present, and can give the positive AIDS test, or if not enough antibodies will give a false negative