Introduction to HIV - The Importance of HIV Testing and Diagnosis

Written by Brian Boyle, MD, JD

If you think you are at even slight risk of having HIV-if you have had numerous sex partners or if you have had sex with someone who might have been bisexual or had a history of intravenous drug use-you should be tested. If you test positive, you can then receive medical care necessary to keep you healthy and prevent the diseases that occur in untreated AIDS patients. If, on the other hand, you wait until you feel sick before you are tested, you may already have progressed to AIDS and your immune system may already have incurred significant damage that may not be reversible.

Pregnant women
Recent advances in therapy have also led to effective methods of preventing mother-to-child transmission of HIV. Virtually every pregnant woman, especially those who have a history of intravenous drug use, have had sex with someone in a high-risk group, or who have had numerous sexual partners, should be tested for HIV. HIV-infected mothers should consider taking antiretrovirals, which can effectively prevent transmission to the infant. Since breast-feeding can also cause transmission of HIV to the infant, HIV-infected mothers should not breast-feed their infants if there is an available alternative. Many states also require testing of the infant at birth, so that appropriate treatment can be provided.

Testing is voluntary and confidential
Under most circumstances, HIV testing is voluntary. Unless there are special circumstances, most states require a person to give specific permission, called informed consent, before he or she can be tested for HIV. Privacy and confidentiality are legitimate concerns for people who are being tested for HIV. Most people do not want other people or organizations, such as their employer, to know they are HIV-infected and most don't even want them to know that they are being tested. Most states have laws that protect the confidentiality of HIV testing and the diagnosis of infection. While accidental disclosure of a person being HIV positive can occur, in my experience it is extremely rare. It's a mistake to avoid testing because of fear of accidental disclosure.

Also, there are other options including anonymous testing in a clinic or at home (for example, Home AccessR), where you are identified by a number, not by name, and no one but you knows your number. The cost of testing is generally between $30 and $100, and some groups, including many health departments, provide testing free of charge.

How Does HIV Testing Work?

HIV is usually diagnosed by a blood test, but newer tests can be done on saliva or urine. If you're squeamish about getting blood drawn, there are alternatives you can discuss with your doctor. Generally, the purpose of the test is to search for antibodies to the virus. The initial test is an enzyme-linked immunoabsorbent assay (ELISA) and is confirmed using a test called the Western Blot. The antibody tests are very reliable, but may not be able to detect an infection during the first six months after an exposure. There is also a test that can test for the presence of the virus itself, and this test is called an HIV PCR. HIV PCR is used to test for HIV after a potential HIV exposure, but before antibodies have developed. Because infants may have their mother's antibodies in their blood confounding the HIV antibody test, HIV PCR is also useful for them. However, HIV PCR may not be reliable in detecting HIV in all infected patients, especially those with a low viral load.

How long do the results take?

It used to take several days to a week to get test results back. Now there are rapid detection methods that allow reliable results in less than an hour. As a result, HIV testing can be completed while you are still in your doctor's office.

Test counseling

Pre-test and post-test counseling and education are important parts of HIV testing. Counseling gives people who test negative for HIV an opportunity to learn more about HIV and how to avoid becoming infected. For those who test positive for HIV, counseling gives them a chance to learn about the importance of being medically evaluated and, if appropriate, treated so as to prevent disease progression or OIs. These counseling sessions take about 15 minutes, including time for questions. They are a very valuable part of the testing process, regardless of the test results.

Conclusion

HIV disease is a chronic disease that used to be fatal for virtually everyone who got it. Now, things have changed and effective treatments are available to treat HIV and, in most cases, these treatments can prevent HIV from doing further damage and can keep the person healthy. In order to take advantage of these treatments, you must be tested and diagnosed with HIV. All persons who may have been infected with HIV and virtually all pregnant women should be tested as soon as possible.

Brian Boyle, MD, JD, is an Attending Physician at the New York Presbyterian Hospital-Weill Cornell Medical Center and Assistant Professor of Medicine in the Department of International Medicine and Infectious Diseases at Weill Medical College of Cornell University. Dr. Boyle has authored and co-authored more than 100 publications and abstracts relating to the treatment of HIV and hepatitis. In addition, he has lectured across the country on the latest advances in the treatment of HIV, Hepatitis C Virus and Hepatitis B Virus as well as many other HIV/AIDS and hepatitis related topics.

next: HIV, AIDS, and Older Adults