Human Immunodeficiency Virus & Acquired Immunodeficiency Syndrome Flashcards
HIV is a retrovirus. What does this mean?
- It undergoes reverse transcription (RNA to DNA)
- The virus targets TH cells causing pronounced
immunosuppression -> opportunistic infections &
opportunist CAs
- The virus targets TH cells causing pronounced
What is the incubation period for HIV?
- 1-3 m but has been reported to be up to several years
HIV is _______ and ________.
Chronic, progressive
What is the relation between HIV and AIDS?
In most cases HIV infection converts to AIDS in about 10 years
T or F:
There is only one strain of HIV.
F, there are 2:
- HIV-1
- HIV-2
How are HIV-1 and HIV-2 different?
Initially HIV-1 was predominant in the USA & western Europe and HIV-2 in west Africa, both are now more global
4 ways HIV may be transmitted:
- Sexual contact with an infected partner
- Contact with contaminated blood & blood products
- Can cross the placenta, and can be passed to the baby
at delivery or through breast milk - Infection from needle stick injury is dependent of site &
depth of injury & also the viral load of the contaminated
blood
In HIV, what is the “window period”?
Time from exposure to when Dx tests can detect HIV. Varies based on the test used & can last up to 3 months
Describe a primary HIV infct:
4
- Can last from weeks to months
- Seroconversion
- Formation of Abs, can extend from 4-12 wks
- Intense viral activity which is denoted as high viral load
- Dramatic decrease in CD4 count
- CD4 is the receptor on T helper cells
What stage occurs following the primary infct of HIV? How long does this stage last?
The latent stage, can last for years
What are the mnfts during the latent stage of HIV?
3
- Pt may be asymptomatic
- Recurrent, opportunistic respiratory infections
- Lymphadenopathy
Describe overt AIDS. What are the requirements?
- Typically 60% - 70% of cases progress to AIDS in
about 10 yr - WHO criteria defining AIDs require > 20 opportunistic
infcts - CDC requires <200 CD4/mm (normal is ~1000) or 1 or
more specific diseases
Regarding HIV to AIDS, who are the rapid progressors, slow progressors, and long-term non-progressors?
- ~5 yr (10% - 20%) = rapid progressors
- > 15 yr (5% - 15%) = slow progressors
- 2% - 5% = long-term non-progressors
In HIV-AIDS, which cells are primarily affected?
3
- Primarily targets TH cells (CD4)
- B cells and
- Macrophages are also impacted
Brief patho of HIV-AIDS:
the immune system is damaged -> severely compromised immunity -> new & latent system-wide infections develop
