AIDS

A A acquired – contagious, not born with it I Iimmune - dealing with the body’s defense system D Ddeficiency – decreased defense capability S Ssyndrome – a collection of symptoms and infections

HIV H H human –virus whose host is a person I Iimmunodeficiency – decreasing immune function in a person V Vvirus – a retrovirus, surrounded by a protein coat, a nucleic acid virus that can self reproduce

HIV Diagram

Origin of HIV First diagnosed in the U.S. in 1981 Assumed to have begun in Africa Possibly transferred from chimpanzees to humans during slaughtering Probably went from Africa to Haiti to the United States Has killed more than 25 million people, making it the most destructive epidemic in history

Stages of HIV infection

Window period Time of exposure to infection Usually less than 6 months Person can be contagious, but not test positive

Stages of HIV infection Asymptomatic HIV+ stage Infection begins No symptoms, but contagious May last from years Window period Time of exposure to infection Usually less than 6 months Person can be contagious, but not test positive

Stages of HIV infection Symptomatic HIV+ stage Fewer than 200 CD4+ T cells per microliter of blood Kaposi’s sarcoma (cancer) Pneumocystis pneumonia Opportunistic infections Last months to a few years Asymptomatic HIV+ stage Infection begins No symptoms, but contagious May last from years Window period Time of exposure to infection Usually less than 6 months Person can be contagious, but not test positive

Testing and Treatment There are HIV tests available There is no vaccine or cure for AIDS. There are medications that slow down the process of destruction. Prevention is the best hope.