According to California HIV/AIDS Statistics from the Center for AIDS Research, Education & Services, an estimated 190,000 people were living with HIV in the state of California as of April 30, 2009, including all of those with and without AIDS.
You can get or transmit HIV through unprotected sex or by sharing needles or other equipment used to inject drugs.
HIV stands for Human Immunodeficiency Virus. HIV is the virus that causes AIDS.
Your immune system is your body's defense system. While many viruses can be controlled by the immune system, HIV targets and infects the same immune system cells that are supposed to protect us from illnesses. These cells are a type of white blood cell called CD4 cells (sometimes called T-cells).