What Is HIV?
HIV (human immunodeficiency virus) is a virus that attacks the immune system. The immune system becomes weaker, making it harder for the body to fight off infections and some kinds of cancers.
Most people who are diagnosed early and take medicines for HIV can live long, healthy lives.
What Is AIDS?
AIDS (acquired immune deficiency syndrome) happens after someone has had HIV for many years. In AIDS, the immune system is severely weakened. Serious infections and health problems happen.
Medicines can help prevent HIV from developing into AIDS.
How Do People Get HIV?
HIV spreads when infected blood or body fluids (such as semen or vaginal fluids) enter the body. This can happen:
- during sex (especially anal sex and vaginal sex)
- through sharing needles for injecting drugs or tattooing
- by getting stuck with a needle with an infected person's blood on it
HIV also can pass from mother to child during pregnancy, childbirth, or breastfeeding.
HIV is NOT spread through:
- pee, poop, spit, throw-up, or sweat (as long as no blood is present)
- coughing or sneezing
- holding hands
- sharing eating utensils or drinking glasses
What Are the Signs & Symptoms of HIV and AIDS?
When first infected with HIV, a person may have:
- swollen glands
- painful ulcers in the mouth or around the anus or penis
- muscle and joint pain
These symptoms go away in a few weeks. In the first few years after infection, someone with HIV may have mild symptoms, like swollen glands.
Because the symptoms of HIV can be mild at first, some people might not know they're infected. They can spread HIV to others without even knowing it.
After a few years, other symptoms start, including:
- weight loss
- increased number of infections
- infections that are more severe than is typical
Without treatment, HIV can lead to a very weakened immune system and progress to AIDS. Illnesses that happen in AIDS are called "AIDS-defining conditions."
AIDS-defining conditions include:
- very fast and severe weight loss (called wasting syndrome)
- a lung infection called pneumocystis pneumonia
- Kaposi sarcoma (a type of skin cancer)
- lymphoma (cancer in immune system cells)
What Causes HIV and AIDS?
HIV destroys CD4 cells (also called T cells). CD4 cells are part of the immune system. They fight germs and help prevent some kinds of cancers.
How Is HIV Diagnosed?
Health care providers usually diagnose HIV through blood tests. Someone who has HIV is said to be "HIV positive."
Tests also are available without a prescription at the drugstore. You can do the test at home.
How Is AIDS Diagnosed?
HIV is diagnosed as AIDS when someone:
- has fewer than 200 CD4 cells
- develops an AIDS-defining condition
How Are HIV and AIDS Treated?
Medicines can help people with HIV stay healthy. They can also prevent HIV from progressing to AIDS.
Health care providers prescribe a combination of different medicines for people with HIV and AIDS. They must be taken exactly as prescribed or they won't work. These medicines:
- help keep the number of CD4 cells high
- reduce the viral load of HIV (how much HIV is in the body)
Regular blood tests will check the number of CD4 cells in the body (called the CD4 cell count) and the viral load.
If an HIV-positive person's CD4 count gets low, doctors prescribe daily antibiotics. This prevents pneumocystis pneumonia, which happens in people with weakened immune systems.
Can HIV Be Prevented?
To reduce the risk of getting HIV, people who are sexually active should:
- use a latex condom every time they have sex (including vaginal, oral, or anal sex)
- get tested for HIV and make sure all partners do too
- reduce their number of sexual partners
- get tested and treated for STDs (sexually transmitted diseases); having an STD increases the risk of getting infected with HIV. To find a testing site, visit the CDC's National HIV and STD Testing Resources.
- consider taking a medicine every day (called PrEP or pre-exposure prophylaxis) if they are at very high risk of getting infected (for example, if they are in a sexual relationship with someone with HIV)
- Do not inject drugs or share any kind of needle.
- Do not share razors or other personal objects that may touch blood.
- Do not touch anyone else's blood from a cut or sore.
What Else Should I Know?
Treatment has improved greatly for people with HIV. By taking medicines and getting regular medical care, HIV-positive people can live long and healthy lives.
People with HIV need a medical care team for the best treatment and support.
If you or someone you know has HIV or AIDS it is important to:
- goes to all doctor visits
- takes all medicines exactly as directed
- goes for all follow-up blood tests
- understands what HIV/AIDS is and how it spreads
- is physically active, gets enough sleep, and eats well
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