AIDS I Flashcards
What retrovirus subtype is the human immunodeficiency virus?
Lentivirus.
Where is HIV-2 found almost exclusively?
Western Africa.
What co-receptors on the surface of the CD4+ T-lymphocytes are necessary for HIV-1 fusion?
CCR5 and CXCR4.
What viral enzyme is required for transcription of HIV-1 proviral RNA into proviral DNA?
Reverse transcriptase.
What HIV-1 enzyme is required for integration of proviral DNA into the host genome?
Integrase.
What HIV-1 enzyme is required for assembly of viral proteins into replication-competent viruses?
Protease.
True or false: There is a period of microbiologic latency between prior to the onset of AIDS.
False. Although there is a period of clinical latency which can last for years (marked by a progressive loss of CD4+ T-lymphocytes), there is never a period of true microbiologic latency.
Following an acute retroviral syndrome, the immune system incompletely clears HIV-1 from the body. Where do HIV-1-infected cells persist?
Within lymphoid tissue.
Where in the world are the greatest numbers of HIV-1 infection occurring today? What is the predominant mode of transmission?
Sub-Saharan Africa (by far). Predominant mode is heterosexual intercourse.
What is the most efficient sexual means of spreading HIV-1?
Receptive anal intercourse. Penile-vaginal intercourse is relatively inefficient when it comes to spreading HIV-1, especially from women to men.
Which is the most frequent period of mother-to-child HIV-1 transmission: prenatal, perinatal, or postnatal?
Perinatal, although prenatal (transplacental) and postnatal (breast-feeding) do occur as well.
What is the standard testing for making the diagnosis of HIV-1 infection?
A serum HIV antibody ELISA screening test and a confirmatory Western blot test.
What must be present for a Western blot to be read as positive for an HIV-1 infection?
An antibody against one protein from each of the three main retroviral genes: env, pol, or gag.
What has been shown to be the strongest predictor of outcome in HIV-1 patients over 1-year to 10-year periods of observation?
The level of HIV RNA in plasma. Declines in plasma HIV RNA concentrations during therapy are strongly associated with a decrease in risk of subsequent disease progression.
What are the six groups of current antiretrovirals?
- Nucleoside reverse transcriptase inhibitors (NRTIs)