2 T Cells T cells are a type of white blood cell There are 3 types of T cells:Helper T cells: also known as CD4+ cells; these detect infection and tell B cells to make antibodiesCytotoxic T cells: attack virus-infected cellsSuppressor T cells: stop the immune system when the fight against the invaders has been won
3 HIV HIV stands for Human Immunodeficiency Virus This virus attacks the Helper T cells (CD4+) of the immune systemA normal CD4+ count is between 500 to cells/mm3 of blood
4 AIDS AIDS stands for Acquired ImmunoDeficiency Syndrome This is the last stage of HIV infectionA person is considered to have AIDS if their CD4+ count is lower than 200 cells/mm3 and has one or more opportunistic infections
5 Opportunistic Infections Occur when the CD4+ count falls below 350 cells/mm3Caused by viruses, bacteria, or fungi that are normally present on or in the bodyPeople with normal immune systems can fight off these invadersPeople with weakened immune systems can’t, so the invaders cause infectionsThat’s why they are called opportunistic, because they take advantage of the weakened immune system
6 Examples of Opportunistic Infections Cytomegalovirus (CMV): causes pneumonia, encephalitis, gastroenteritis, and retinitisKaposi’s sarcoma: cancer of the blood vesselsPneumocystis carinii pneumoniaWasting syndrome: causes loss of more than 10% of body weight and is accompanied by more than 30 days of diarrhea or weakness and fever
7 HIV TransmissionHIV is transmitted through the exchange of body fluidsFor example:Sexual contactPregnancy, childbirth and breastfeedingInjection drug use (sharing needles)Blood transfusion and organ transplant (very rare in the U.S. because of screening)Occupational exposure (healthcare workers)
8 Statistics (2012)An estimated 47,500 Americans are newly infected with HIV each year.There are approximately 1.1 million Americans who are living with HIV/AIDS.The CDC estimates that 16% of HIV-positive people don’t know they are infected— meaning they may be transmitting HIV without knowing it.People of color are at disproportionate risk for HIV infection. The incidence rate for African Americans is 8x the rate for whites
9 Common Myths A person with HIV or AIDS looks sick. Only gay people get HIV/AIDS.Some people have been cured of HIV.HIV isn’t a big deal anymore. A person can take a pill once a day and be fine.Being HIV-positive is the same thing as having AIDS.A person can get HIV from touching or kissing someone with HIV.I am not at risk because I am in a monogamous relationship.