Term
| what kind of behavioral determinants, ecological determinants that increase susceptibility to STD acquisition? |
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Definition
3 behavioral determinants: number of partners, sexual practices, frequency of intercourse
3 ecological determinants: healthcare access, patterns of partner mixing, rate of acquiring new sex partners. |
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Term
| what are risk factors influencing the efficiency of transmission of STDs? (host and susceptible) |
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Definition
host: the presence of other STDs and secondary infections, circumcision
infected: stage of infected (size of inoculum)
wearing a condom |
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Term
| how does health care access, quality and utilization change how STDs manifest themselves in a population? |
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Definition
| lower healthcare access, quality and utilization will make the incidence and severity of STD cases worse. |
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Term
| what is the difference between HIV and AIDS? |
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Definition
| HIV is the virus and AIDs is the disease. you can have the virus without the disease or onset of symptoms. |
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Term
| What do the acronyms mean? |
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Definition
HIV - Humman Immuno Virus
AIDS - Acquired Immuno-Deficiency Syndrome |
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Term
| Which family of viruses does HIV belong to? |
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Definition
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Term
| what human cells does HIV reproduce within? |
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Definition
| in Cytotoxic T cells (with CD4 receptors, which the virus is able to bind to) |
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Term
| is the HIV host infectious during the latent period? why? what is going on during this period? |
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Definition
| they are infectious during the clinical latent period but not too infectious. this is when the viral numbers and building and the immune system is slowly being depleted. |
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Term
| what is the implication of T-cell and macrophage infection? |
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Definition
| your T cell count is indicative of the severity of the infection. |
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Term
| what is the size of the HIV genome and how many proteins does it code for? |
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Definition
| 9.8kb pairs and 12 proteins. |
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Term
| what receptor does the main coat protein in HIV have a strong affinity for. where are these receptors and what is the coat protein called. |
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Definition
| binds to CD4 on the cell surface of Cytotoxic T cells. the coat protein of the viral capsid is gp 120 and it is what has a high affinity for CD4 |
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Term
| what are the implications of the high HIV mutation rate? how does this affect treatment? |
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Definition
| it means that the virus is constantly changing which works in its advantage because it is able to evade antibiotics and the immune system this way. |
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Term
| what are some examples of opportunistic infections as a result of hiv? (name 3) |
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Definition
| tuberculosis, herpes, Salmonella, Toxoplasmosis |
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Term
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Definition
| Diverse population of strains within one host. Arise, in the case of HIV, due to the high mutation rate. |
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Term
| diagram HIV replication within a host cell. what is the difference between HIV replication and the replication of non retrovirus viruses. |
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Definition
1. HIV gp120 fuses binds to CD4 receptors of the cytotoxic T cells
2. virus fuses with cell membrane and deposits its RNA into the cell
3. reverse transcriptase of the cell sytnehsizes HIV RNA into DNA
4. HIV DNA enters cell nucleus and integrates itself into the cell genome
5. cell genome transcribed and viral RNA leaves the nucleus
6. RNA is translated into a viral protein
7. viral protein is repackaged along with viral RNA into a new virus which leaves the cell. |
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Term
| what is the trend in T-cell count and viral count from acquisition of HIV to death? |
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Definition
| after initial infection T cell count rapidly drops resulting in acute HIV syndrome. then it recovers a little and continues with a slow decline to nothing as the infection progresses and the viral count slowly increases (finally increasing sharply at end as T cell count crashes) |
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Term
| what determines the eventual severity of AIDS symptoms and how long it takes to get there? |
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Definition
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Term
| what are CTLs? how do they recognize other CTLs infected with viral peptides? |
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Definition
| Cytotoxic T lymphocytes are the macrophages that seek out virus infected cells and destroy them, reducing virus spread. they do this by detcting viral peptides which are displayed on the surface of infected cytoxic T cells. |
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Term
| what is the relationship between CD4 and virus abundance over the course of the hiv infection? what is happening to the viral replication rate? what is happening to viral diversity? what happens at the end of the infection? any other relationships (viral abundance, diversity, replication rate, strain abundance....?) to note over the course of the infection? |
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Definition
• A. CD4 numbers inversely related to the viral abundance.
• B. Viral diversity increases over the course of the infection and then drops off right at the end when a few strains of virus dominate the viral landscape.
• C. Loook how all interesting stuff happening with viral replication and abundance which isn’t communicated through CD4 numbers. There are tons of peaks in the viral replication rate that seem to correspond to drops in diversity
• D. reflects what all the other graphs are telling us. The peaks in the replication rate are caused by only one strain (hence the decrease in diversity) strain abundance for everything drops off at the end while a few strain’s abundances skeyrocket at the end of the infection. This is why the viral diversity index drops off. |
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Term
| according to the phylogenetic tree of various immunodeficiency viruses, from what did humans get the HIV1, HIV2? who had it first? |
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Definition
humans got HIV 1 from the apes and HIV 2 from mangabeyes. HIV-1 is most responsible for the human epidemic
This disease probably first evolved in monkeys. Then, great apes like chimps became infected by monkeys (through hunting) and eventually we, humans, got it from chimps |
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Term
| when was HIV first described? since when has it been with us? where was it when it first began? |
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Definition
| HIV was described in 1983 when really it has been with us since the 30s or 40s. • we didn’t know it existed back then because of the slow progression of the disease and because it was isolated to the congo basin, a place where not very many people worked. |
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Term
| what are the three possible scenarios for HIV-1 introduction into humans and diversification? what are the 2 more likely scenarios. on a time-scale, which scenario has HIV being in humans the earliest, which the latest? |
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Definition
• Transmission early says that HIV’s entrance into the human line goes way back. HIV maintained itself in the population and then finally diversified.
• Tranmission Causes Epidemic says immediately after spillover, there was diversification (and an epidemic).
• Parallel late transmission says that diversification occurred earlier, in the chimps. Really, the difference is how much time has to elapse.
• Prof sense is that scenario 1 and 2 are the most correct and the real question is how long is that single red piece. |
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Term
| when did the common ancestor of the HIV - 1 M group come into existence? |
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Definition
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Term
| what are the four main routes of transmission? which are primate --> human, which are human ---> human. |
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Definition
| bushmeat, sexual, blood product , and mother-to-child. bushmeat is the primate to human one and rest are forms of human to human transmission. |
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Term
| what is the most efficient route for human ---> human transmission. second most efficient? why is HIV an STD if that is such an inefficient way to transmit the infection? |
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Definition
| blood transfusion. STD because predominantly passed via sexual activity, even though transmittance that way is not that good. |
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Term
| why is HIv the "revenge of the vanquished?" |
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Definition
| because we are currently wiping chimps out, they are on the verge of extinction, and they gave this horrible disease to us. |
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Term
| what are some factors that affect transmission rate of STDs? do they increase or decrease transmission risk? |
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Definition
• Lesions or other STDs increase risk
• Circumcision reduces risk by ~50%
• Needle exchange programs reduce risk
• Condoms reduce risk but using spermicidal gels increases risk
• Abstinence only programs are not effective
• Vertical transmission can be reduced via antiretroviral treatment and cesarian delivery |
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Term
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Definition
| the cocktail of drugs used to treat AIDs. Highly Active Anti Retroviral Therapy |
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Term
| why are people's responses to HAART different? |
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Definition
| b/c people have different strains of HIV |
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Term
| what are some HIV vaccine strategies? have any been successful? |
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Definition
• Naked DNA containing one or more HIV information strands
• Viral surface proteins
• Combination of elements (e.g., gp 120 proteins and live vector
• Live vector viruses (non-HIV viruses engineered to carry genes encoding for HIV proteins
• HIV peptides (protein fragments)
• Pseudoviruses (artificial viruses)
• Whole killed HIV
• Live attenuated HIV
none have been successful. |
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Term
| where is HIV most prevalent? what is the prevalence there? how has that affected society structure and average lifespan? GDP? |
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Definition
| sub saharan africa. kills all the adults and really taking its toll on the nation's economy (reduces GDP). life expentancy halved in some places. |
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Term
| what percent of the world's AIDS cases come from sub saharan africa |
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Definition
| 64% of the whole world's cases are from africa. |
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Term
| how is government leadership in fighting the epidemic affect it? |
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Definition
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