Lecture 27 - HIV Flashcards
(31 cards)
what is a common feature of AIDS?
extreme sickness and weight loss
what does HIV stand for
human immunodeficiency virus
what does AIDS stand for
acquired immune deficiency syndrome
- later in life
what are three common AIDS infections?
- oral mucosal candidiasis (fungal)
- pneumocystitis carinii pneumonia (only in AIDS and chemo patients)
- cytomegalovirus infection (usually never an issue)
what is Kaposi’s sarcoma
a rare cancer caused by human herpes virus 8, which normally causes no issue but causes cancer in HIV/AIDS infected people
- physically recognisable marker of AIDS
what are Taxoplasma brain abcesses
abcesses within the brain caused by toxoplasmic gondii (protozum) from cat feces
- common in people but never causes issue until HIV/AIDS weakened immune system
can we treat toxoplasma brain abcesses?
medicine can get rid of the abcesses and return brain function to normal
aids defining illnesses write in binder?
yes
how do people with HIV end up dying?
they get a large number of different diseases one after another until they get so weak that one of those illnesses kills them
which disease is HIV similar to in terms of transmission?
hepatitis B virus
where does HIV infect?r
helper lymphocytes
- CD4+ T cells
no other cells get infected.
HIV is what type of virus?
retrovirus
what is HIV closely related to?
apes in central africa
- humans killing chimpanzees, which were infected with a simian immunodeficiency virus which is closely related to the human IV. blood from infected chimps got into their wounds
how many introductions of SIV into humans were there?
5 origins
where did HIV spread?
from central africa to urban africa, to haiti, then to US and europe
what 3 things effected the epidemic spread of HIV?
- prevalence of infection
- rate of sexual parter change
- rate of unsafe injecting drug use
describe HIV structure
- enveloped retrovirus containing spike proteins specific for helper lymphocytes
- nucleocapsid containing two strands of RNA
how does HIV replicate differently?
viral RNA is copied into DNA by viral reverse transcriptase and embedded into the host cell’s genome, which is backwards (should be DNA-RNA-protein-new virus)
true or false, the infected host cell (HIV) will always be producing new viruses
no, only when the host cell is required to do its job/be activated does it produce new viruses. so if the virus is inside a m. tuberculosis T cell lymphocyte, then they may never get AIDS
describe the rapid evolution of HIV during infection
- continuous production of HIV during infection
- Highly error prone copying of HIV RNA, so generation of a wide range of mutant viruses every day
describe the time course of untreated HIV
- 4-6 weeks after infection, extremely high viral load
- cytotoxic T cells kill infected T helper cells, level of HIV AND helper T cells falls, creating glandular fever like symptoms
- B cells produce ABs against HIV, and so level of HIV remains stable for many years
- helper t cell levels become far too low and AIDS happens, and HIV in blood rises again
what is the best way to diagnose HIV?
detect antibodies
- in blood or even saliva
or detect HIV genome in blood with PCR
which diagnosis method works earliest for HIV?
PCR
which drug prevents action of reverse transcriptase?
tenofovir and efavirenz
