HIV stands for Human Immunodeficiency Virus. It is a virus that attacks the human immune system. It is the virus that causes AIDS.


AIDS stands for Acquired Immunodeficiency Syndrome. It is the result of HIV attacking the human immune system to the point where the body cannot fight off various diseases and illnesses (called opportunistic infections) that typically don’t affect a person with a healthy immune system. AIDS is the most advanced stage of HIV and can only be diagnosed by a doctor. 

There are two ways that doctors decide when a person living with HIV is considered to have advanced to an AIDS diagnosis:

  1. From other infections: When a person’s immune system is so weakened by HIV that s/he gets one or more opportunistic infections.
  2. From certain blood tests: Doctors can perform specific tests that measure how well the immune system is working (commonly known as a CD4 Count) and how much virus is in the body (known as a viral load test).

How quickly someone with HIV advances to AIDS depends on many different factors. One important factor is how soon after acquiring HIV a person is diagnosed and gets into care. Also, just like any other health problem, different people’s bodies respond differently to HIV. So, it is important to get tested, get medical care if you are positive and protect yourself and your partner(s).


You can only acquire HIV by coming into direct contact with certain body fluids from a person with HIV who has a detectable viral load. These fluids are:

  • Blood
  • Semen (cum) and pre-seminal fluid
  • Rectal fluids
  • Vaginal fluids
  • Breast milk

For transmission to occur, the HIV in these fluids must get into the bloodstream of an HIV-negative person through a mucous membrane (found in the rectum, vagina, mouth, or tip of the penis); open cuts or sores; or by direct injection.

People with HIV who take HIV medicine daily as prescribed and get and keep an undetectable viral load have effectively no risk of sexually transmitting HIV to their HIV-negative partners.

For more information, visit HIV.gov.


HIV can affect anyone regardless of their identity. Certain behaviors can increase a person’s vulnerability to HIV.

  • HIV is most often acquired through anal or vaginal sex or sharing needles or syringes with a person living with HIV with a detectable viral load. Strategies like condom use, PrEP/PEP, clean needle exchange are just a few of the multiple ways to prevent HIV acquisition regardless of sex and needle use behaviors.
  • It is also possible for a baby to acquire HIV during birth or a breastfeeding if the mother is living with HIV. If the mother is on HIV medication prior to delivery and abstains from breastfeeding, the baby can be born without HIV and maintain an HIV-negative status.


Project ARK currently offers free, confidential on-site testing for HIV, syphilis, and Hepatitis C. We can assist you with finding additional STI testing and treatment resources.


There are several different types of HIV tests, such as in-home HIV testing, but the most common type is a rapid or conventional blood test.  HIV blood tests use a sample of blood, either from a finger prick or a larger sample often taken from the inner arm, to test for antibodies or antigens. 

Traditional HIV test results can take one to two weeks to come back from a lab, but rapid tests are now widely available that can provide a result in about 20 minutes. 

Project ARK currently offers a rapid finger prick and blood draw testing methods. 


Most HIV tests check for antibodies that the body produces once someone has acquired HIV. Antibodies are cells produced by the body’s immune system to fight off all different kinds of infections, including HIV.  If an HIV test detects HIV antibodies, a person has acquired HIV.  If antibodies are not present, a person is most likely not living with HIV. But, it can take as long as three to six months for the body to develop enough antibodies to show up on a test. 

The time period between acquiring HIV and a positive HIV test result is called the “window period.”  During this “window period” you could test negative for HIV but still have acquired HIV and able to transmit the virus to others. Therefore, it is important to get tested (or re-tested) after a sufficient period of time has passed to know for sure.


The Centers for Disease Control and Prevention (CDC) recommends HIV testing for everyone between the ages of 13 and 64 (especially if you are sexually active or have never been tested). This does not mean though that testing is done automatically when you see a health care provider even if you have blood drawn. The only way to know for sure you are being tested is to ask to be tested.  

HIV testing is also recommended for all pregnant women as a routine part of prenatal care. A person who is living with HIV and pregnant can take certain medications during pregnancy that, combined with medical care, can significantly lower the chances of the baby acquiring HIV.


Project ARK now offers HIV testing on an appointment and walk-in basis Mon-Fri. 

To schedule a same day appointment, call (314) 535-7275, Option 1 right at 9am Mon-Fri and leave a message. You will receive a call back and informed if a same day testing appointment is available .

To access walk-in testing, you can come to our location at 4169 Laclede Avenue, 63108 on Tuesdays and Thursdays from 5-7pm.


HIV testing at Project ARK is FREE and available at a number of other local organizations for free or low cost.

To find other testing sites, visit: http://gettested.cdc.gov/ .


The most important thing to do if you test negative is to stay negative. Use condoms each and every time you have sex—vaginal, anal, or oral—no exceptions. Get tested regularly, talk to your partners about HIV and ask that they get tested with you. You want to make sure that they know you’re watching out for their health and yours. If you use needles, don’t share them.

A negative HIV test is also an opportunity to learn more about PrEP (Pre-Exposure Prophylaxis). PrEP is taken to prevent HIV infection. Talk to our prevention counselors or visit https://www.cdc.gov/hiv/basics/prep.html to learn more about PrEP.


With the availability of treatments today, you can lead a long and healthy life as someone living with HIV.  The most important thing to do if you receive a positive HIV test result is to get connected with services and support as soon as possible. Advances in HIV/AIDS treatment are occurring all the time. Medical treatment and a healthy lifestyle can help you stay well much longer than in the early years of the epidemic. But, the longer you wait after testing positive to see a health care provider, the greater your chance of developing serious health problems.   

If you’ve tested positive for HIV, here are some important steps to take to protect your health:

  • See a doctor, even if you don’t feel sick. If possible, see a doctor who has experience treating HIV. Consulting someone about your treatment options is the first step towards staying healthy.
  • Find a support system. The emotional and physical challenges ahead can be difficult, and having people around to help is important. Ask your doctor about counselors and support groups that can help you.
  • Talk with your partner(s). Tell your sexual partner/s about your HIV status and make sure you reduce your risk of transmitting the virus by practicing safer sex, including using latex condoms (with water-based lubricant) or dental dams each and every time you have sex. 
  • Consistently take your medicines. HIV medications improve the quality of life for people living with HIV and help prevent new diagnoses of HIV in the community. When a person living with HIV consistently takes their medicines and achieves an undetectable viral load they are no longer able to pass HIV through sex. Undetectable equals Untransmittable (U=U). To learn more visit: https://www.cdc.gov/hiv/basics/livingwithhiv/protecting-others.html.