HIV 1 - epidemiology etc Flashcards
Early epidemiology of HIV and turning point
Common in homosexuals, immigrants, drug users, poor. Then heterosexual spread and transfusion recipients.
Progress against it up to 2000
Test for HIV AB in mid 80s, able to prevent mother-to-child in mid 90s, HAART in mid 90s
Epidemic by the numbers
About 35 million infected in world, newly infected is 2.3M/year, deaths are over 1M/year.
How much is HIV spread sexually? what is the other percent?
About 80%. Also can be mother-to-child (helped with therapy), injection drugs, transfusion, needlestick (low)
Opportunistic infections with HIV
TB, mycobateria, fungal, pneumonia, others (thrush, shingles)
Risk categories by gender in Canada
Men: highest in homosexual contact, then drugs, then heterosexual. Female: most is heterosexual contact, then drugs. Hetero females are at high risk
AIDS defn
low CD4 (<200), and other opportunistic infections
WHO
set new targets and guidelines to help control it. goal was 3M by 05. Still only reached 20% of people affected, barriers to ART, costs to patients.
Societal impact in African countries
Life expectancy dropped significantly in 80s/90s. Forced to choose b/w school and ART and malaria Tx. Uganda: political campaign promoting ABC (abstinence, be faithful, condoms).
Needlestick injury
Usually very low risk (.42%). Factors depend on wearing gloves, type of needle (venous needle more), viral load of patient (if on therapy it is lower). Wash with sad and water, call for risk assessment, consider ART prophylaxis.
Why does HIV spread so much?
86% is heterosexual (truckers, prostitutes, trade routes). Most is transmitted with acute infected people, i.e. early on and not diagnosed probably (in AIDS and chronic patients, transmission is much lower/# of contacts)
General targets to prevent HIV transmission
Decrease exposure (ART lowers HIV in sex fluids), block transmission (condoms), block entry of virus to new cells, treat after exposure,
Mother to child transmission
Risk is 25-40%. Can be before, during and after birth (breast feeding = 10-20% w/o ART). ART helps; C section reduces risk; formula
Male circumcision
decreases transmission by 50%. Apparently there are many cells that are likely to absorb HIV and other infections there.
Pre-exposure of ART for HIV negative people?
For MSM, sex workers, and partners with a known patient. Shown to work to some degree (need to take pills!), but not every group. Issues: Resistance
