HIV/AIDS Flashcards
what year did HIV appear and where?
1981, LA
how many cases were documented within a few months?
5
who were the first cases of people to be infected?
young homosexual men who appeared healthy except for fever, weight loss and rare infections
similar reports from all over the country being released
extremely rare and aggressive clusters of _____ sarcoma were an initial symptom
Kaposi’s
how many cases were reported in LA by the end of 1981?
270 reported cases of severe immunodeficiency among homosexual men
what were the risk factors at the start and later?
start = number of sexual partners and recreational drug use, later = haemophilia
who was one of the 1st UK citizens to die from AIDS?
Terrence Higgins
____ million people live with HIV globally
36.7
___% are unaware they have HIV
30
____ new infections are transmitted each year
fewer
___% prevalence in southern/eastern africa
___% prevalence in swaziland
7.1, 27
sufferers in developed countries have better access to treatment,
UK → __% of sufferers are on antiretroviral drugs compared to __% in south east africa
96, 54
how is HIV transmitted?
→ blood and blood by products
→ semen
→ vaginal fluid and secretions
→ any body fluid that has mixed with infected blood
→ sometimes breast milk and across the placenta
(not saliva)
describe the asymptomatic period of HIV
when first infected, flu like symptoms persist for around 6 weeks,
after this, asymptomatic period can last up to 15 years
symptoms of AIDs and compromised immune system include:
shingles, lip warts, muscle wastage, PCP (Pneumocytis pneumonia), kaposi’s sarcoma, thrush
how does combination antiretroviral therapy work
→ controls viral replication
→ allows immune system to recover
→ allows infected individuals to live healthy productive lives (but is not a cure)
→ gives hope for control of HIV spread
why was the UN ‘fast track’ treatment scheme too optimistic about HIV decline?
treatments are expensive
what does antiretroviral treatment comprise of?
fusion and entry inhibitors:
(so the HIV vision can’t enter cells)
intergrade inhibitors:
(prevent HIV DNA becoming integrated into hosts DNA)
protease inhibitors:
(prevent formation of new viruses)
describe features and functions of a HIV virion
→ retrovirus with 2 mRNA strands
→ reverse transcriptase and integrase enzymes incorporate viral genome into hosts DNA
→ protease enzymes helps form new viruses
→ envelope with GP120 and GP40 that bind to CD4 receptor on host cells
viral load =
amount of HIV RNA copies per ml of plasma in blood
acute phase 0-12 weeks after infection (viral load) =
rapid increase in viral load
subsequent drop as immune system responds
chronic phase 12+ weeks (viral load) =
slow increase in viral load over years until threshold of AIDS is reached
(acute → chronic → aids)
when viral loads reaches a certain critical point a person has AIDS
acute phase 0-12 weeks after infection (T cell depletion) =
sudden drop in lymphoid and circulating T cells
T cell count recovers (immune system responding)
chronic phase 12+ weeks (T cell depletion) =
slowly declines as viral load increases
