HIV/AIDS Flashcards
AIDS
acquired immune deficiency syndrome - an infectious disease caused by HIV
transmission can occur via:
- vertical transmission (mother > child)
- transmission via bodily fluids (needles)
- via sexual transmission
SIV
simian immunodeficiency virus
- virus found in numberous strains, in primates
factors contributing to the spread of HIV in the early 20th century
- Guns - hunt bigger animals
- Hospital - reuse syringes for injections/poor sterilization
- Forced labour - slavery/camps/malnutrtion/diseases/poor conditions
- Sex work & STD’s - growing cities - coinfections
- Transport - disease spread to major cities
hunter theory
jump from chimpanzee > man
hunter bitten by animal/butchering meat = blood to blood contact
HIV
the causative agent of AIDs
2 main strains: HIV-1 (moved into human population from chimpanzee) / HIV-2 (restricted to west Africa - less virulent in human population)
how did HIV cross the atlantic
Haitian from Afria>US
HIV is a
Lentivirus - slow virus
Infection>AIDS 9-10 years
AIDS>death 9 months (if untreated)
long incubation period = HIV takes long time to show symptoms
what does HIV infect
CD4 T-cells
treatment for HIV
HAART - highly active antiretroviral therapy = increase survival >15 years
how do you loose acquired immunity from HIV
- virus infection kills T cells directly
- increased rate of apoptosis in T cells
- immune system targets infected T cells
=decrease T cell count = loose acquired immunity
vertical transmission
transmission of an infection from mother to child during perinatal period (immediately before and after birth)
differences between HIV/AIDS and cholera,TB, BP, LD
- AIDS = caused by virus
- high mutation rate
- hard to target - HIV does not directly kill - destroys T cells
- AIDS is incurable
- AIDS is sexually transmitted disease
viral swarm
a group of viruses of the same species but with slightly different genetic sequences
why is AIDS hard to target
- attaches to host cell
- releases genes into host cell
- viral components replicate inside cell
- viral components assembled
- viral particles released
super spreaders
R0 = average no. of new infections from 1 infected individual in a population of fully susceptible hosts
- contacts per unit time
- transmission probability
- duration of infectiousness
typhoid mary
worked as cook and infected people with bacterial disease - typhoid fever: contaminated food = was a carrier
