HIV and AIDS 101 - The Basics

• What is HIV?
• What are the stages of HIV?
• What is AIDS?
• How is HIV spread?
• Who is at risk for HIV?
• Can you tell if a person has HIV by looking at them?
• Is there a cure for HIV?
• Hasn't Magic Johnson been cured of HIV?
• Are the HIV cures I read about on the Internet real?

What is HIV?

HIV stands for Human Immunodeficiency Virus. It’s similar to other viruses, such as colds and the flu, with one important difference—the human body cannot get rid of HIV. That means once a person has HIV, he or she has it for life.

HIV affects specific cells of the immune system (called CD4 cells). Over time, HIV can destroy so many of these cells that the body can’t fight off infection anymore.
There is no cure, but with proper medical care, the virus can be controlled.

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What are the stages of HIV?

HIV is a progressive disease, meaning it advances or worsens over time. If a person is infected with HIV and doesn’t get treatment, it will eventually overwhelm his or her immune system and lead to acquired immune deficiency syndrome (AIDS).

The stages of HIV are:

• Acute (Severe) Infection—Occurs as early as 2 to 4 weeks after infection (but sometimes as long as 3 months later); some people report flu-like symptoms during this time, but others have no symptoms at all. People with HIV are very infectious during this time, meaning they can pass the disease on to others. Symptoms can include night sweats, swollen lymph nodes, sore throat, rash, fatigue, muscle aches, and ulcers in the mouth.
• Clinical Latency (Dormancy or Inactivity)—After the initial infection, the virus becomes less active in the body, but is still present. This period can last up to 10 years (sometimes longer), and many people do not have any symptoms of HIV during the clinical latency (or dormant/inactive) period. However, they can still give the infection to others at this time.
• AIDS—This is the last stage of HIV infection; the person’s immune system is badly damaged and he or she becomes susceptible to opportunistic infections (illnesses that attack weakened immune systems). Symptoms can include diarrhea, night sweats, fatigue, fever, chills, vomiting, and severe weigh t loss.

For more information visit the Stages of HIV page.

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What is AIDS?

AIDS stands for Acquired Immune Deficiency Syndrome.  It is the final stage of HIV infection. People in this stage of the disease have badly damaged immune systems and are vulnerable to other infections, called opportunistic infections. These are infections that occur because of a weakened immune system. People are diagnosed with AIDS when they have one or more specific opportunistic infections, certain cancers, or a very low number of CD4 cells, which are important parts of the immune system.

People are generally diagnosed with AIDS when they have both a low CD4 count and one or more opportunistic infections.

For more information on Opportunistic Infection, please see CDC's brochures on Opportunistic Infection.

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How is HIV spread?

There is no cure for HIV, but you can prevent HIV infection. HIV is transmitted from one person to another:

• By having sex (anal, vaginal, or oral) with a person who has HIV. HIV can be transmitted through blood, pre-seminal fluid, semen, and vaginal fluid.
• By sharing needles, syringes, or other injection equipment with a person who injects drugs and has HIV.
• Through pregnancy, birth, or breastfeeding. Women who have HIV can give the disease to their babies before or during birth or through breast-feeding after birth.

To reduce your risk of getting HIV

• Don't have sex at all (anal, vaginal, or oral).
• Only have sex (anal, vaginal, or oral) if you are in a mutually monogamous relationship and you have both tested negative for HIV.
• Use a condom every time you have anal, vaginal, or oral sex.
• Do not share needles or other drug “works” (cotton, cookers, etc.) with anyone else.

More detailed information about preventing HIV can be found in the Prevention section of this website.

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Who is at risk for HIV?

Anyone can be infected with HIV. However, certain groups of people are disproportionately affected by HIV. This means that these groups have more HIV infections than other groups, even though their overall group size is small. In the United States these groups are disproportionately affected by HIV: gay/bisexual and other men who have sex with men (MSM), blacks/African Americans, and Hispanics/Latinos. Women—including those who are pregnant—also face risk. Those who abuse intravenous drugs and other substances are also at high risk.

If you think you are at high risk for exposure, or you have sex partners who may be, you should be tested for HIV at least once each year.  Everyone between ages 13 and 64 should be tested at least once as part of routine health care.

Gay, Bisexual, or Other Men Who Have Sex with Men (MSM)
Gay, bisexual, or other men who have sex with men (MSM) represent approximately 2% of the U.S. population, but accounted for more than 61% of all new HIV infections in 2009.

Other relevant statistics for MSM

• Nearly 24,000 MSM are newly infected with HIV each year (CDC estimates that approximately 50,000 total people in the United States are newly infected with HIV each year).
• MSM is the only risk group with increasing numbers of new HIV infections.

To learn more about these statistics, visit CDC’s page on HIV among Gay, Bisexual and Other Men Who Have Sex with Men (MSM).

Blacks/African Americans
Blacks/African Americans are the racial/ethnic group most affected by HIV. They represent approximately 13% of the U.S. population, but accounted for approximately 45% of all new HIV infections in the United States in 2006.

Other relevant statistics for blacks/African Americans

• At some point in their lives, 1 in 16 black/African American men and 1 in 32 black/African American women will be diagnosed with HIV. Black/African American men are six times more likely to be infected with HIV infection than white men, nearly three times more likely than Hispanic/Latino men and twice as likely as black/African American women.
• It is 15 times more likely for a black/African American woman to be infected with HIV infection than a white woman and nearly four times more likely than Hispanic/Latina woman.

To learn more about these statistics, visit CDC’s page on HIV among African Americans.

Hispanics/Latinos
Hispanics/Latinos represent approximately 15% of the U.S. population, but accounted for 17% of new HIV infections in the United States in 2006.

Other relevant statistics for Hispanics/Latinos

• The rate of new HIV infections among Hispanic/Latino men is more than double that of white men.
• The rate of new HIV infections among Hispanic/Latina women is nearly 4 times that of white women.

To learn more about these statistics, visit CDC’s page on HIV among Hispanics/Latinos. 

Women
In 2006, women comprised 27% of all new HIV infections in the United States. Women of minority races/ethnicities are especially affected. Black/African American women are the most affected group, followed by Hispanic/Latina women. The HIV infection rate for black women was nearly 15 times as high as that of white women and nearly four times as high as that of Hispanic/Latina women.

Women who are infected with HIV typically get it by having sex with a man who is infected or by sharing needles with an infected person.

Pregnant Women
All pregnant women should know their HIV status.

Pregnant women who are HIV-positive can work with their health care providers to ensure their babies do not contract HIV during pregnancy, delivery, and/or after delivery (through breast milk). It is possible for a mother to have HIV and not spread it to her baby, especially if she knows about her HIV status early and works with her health care provider to reduce the risk.

Out of 50 pregnant women with HIV, the risk of them passing HIV to their babies is approximately:

• 1 baby out of 50 when women begin treatment during pregnancy
• 5 babies out of 50 when women begin treatment during labor, or their babies get treatment soon after birth, or both mother and baby receive treatment during labor or soon after birth
• 13 babies out of 50 when women do not get treatment

Remember that HIV also can be spread through breast milk, so mothers with HIV should not breast-feed their babies.
For more information on pregnant women and HIV visit section on this topic.

Intravenous Drug Users (IDUs)
In 2006, people infected with HIV through injection drug use (IDU) accounted for 12% of all new HIV infections. People who have sex with an injection drug user are also at risk for infection through the sexual transmission of HIV.
While most people who have HIV get it by having sex with someone who is infected, sharing needles and other drug works is a well-documented way of transmitting HIV.

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Can you tell if a person has HIV by looking at them?

No. Not everyone with HIV looks sick, and many people have it but don’t know they’re infected. 
Some people who are infected with HIV report having flu-like symptoms 2 to 4 weeks after exposure. Specific symptoms can include fever, enlarged lymph nodes, sore throat, and rash. These symptoms can last anywhere from a few days to several weeks. During this time, HIV infection may not show up on an HIV test, but people who have it are highly infectious and can spread the infection to others.

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Is there a cure for HIV?

No. Many researchers continue to work to find a vaccine that will prevent HIV infection, as well as treatments that may one day cure HIV. There are, however, medications that can help many people infected with HIV live with the disease, stay as healthy as possible, and prolong their lives. It is important that individuals get tested for HIV, and start medical care and treatment as soon as possible to have the greatest effect.

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Hasn't Magic Johnson been cured of HIV?

No. Irving “Magic” Johnson announced he was infected with HIV in 1991. Like many Americans living with HIV, Mr. Johnson takes medication each day to reduce the amount of HIV in his body. For some people, HIV medications work so well that HIV is “undetectable” in a blood test. This does not mean that they no longer have HIV; it just means that the blood test cannot detect HIV because the numbers of viruses in the blood are so low. This reduction in the amount of HIV in the body is good news and can keep people living with HIV from getting sick. But if Mr. Johnson stopped taking his medication, it is likely that he would see the levels of HIV in his body rise and his health would eventually be at risk.

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Are the HIV cures I read about on the Internet real?

No. There is no cure for HIV infection.  Some people have claimed to have discovered a cure for HIV and attempted to sell these cures to people living with HIV.  Many of these fake “cures” can do additional physical and mental harm to people living with HIV and prevent them from seeking proven treatments and support that can extend their lives.

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