HIV 101: the basic information

The Introduction

Philip and I discussed this today and decided it was necessary to provide a basic lesson on HIV and to frame it within the political context in the United States. We figure most of you will already know the information here, and some of you won't. We also figure some people who don't know won't bother to actually learn from this post, but we also believe that we have an obligation to provide facts about HIV.

HIV: What it is

HIV stands for the Human Immunodefeciency Virus. HIV is believed to cause AIDS, or Acquired Immune Defeciency Syndrome. One can be infected with HIV and not have AIDS. One can also be both HIV positive and have AIDS. AIDS is a clinical classification which requires a specific measure of blood cells, called CD4's, and the presentation of certain opportunistic infections.

The virus makes people sick by hijacking their CD4 cells and turn them into factories producing more HIV. The cells ultimately collapse and die from this activity.

Some people with HIV will go on to develop AIDS, some will develop a syndrome where their immune system gets depleted and allows non-AIDS associated opportunistic infections, and some people will remain completely healthy. Those who remain healthy are called non-progressors, and research shows they may have a genetic protection from the virus.

Clarifying the basics on tests

Testing for HIV is a simple test. It can be done either via a blood draw, or with a simple cheek swab. The tests which are run on the fluid sample from your body test for the presence of the antibody to HIV.

An antibody is a special chemical marker created by the body to identify and mobilize against infectious and other foreign agents in the body.

Labs in Michigan test your fluids for the antibodies with two different tests. The first test, called an ELISA test, is run three times. If it comes back positive all three times, a second more sensitive test is run. The second test is the Western Blott. The Blott tests for antibodies to specific genes of the virus.

If the three ELISA tests and the one Western Blott are positive, a person is considered to be HIV-positive. The tests are often repeated to confirm the diagnosis.

A positive test for HIV does not mean a person has AIDS, or will develop AIDS. It merely means the person has been infected with HIV and that their immune system has responded to the virus.

A negative test does not necessarily mean a person is not infected. It merely means that the body has not developed antibodies to the virus yet. A person could be infected for as long as 6 months without testing positive for the antibodies. Even though they do not test positive, they can still spread the virus to others.

When some one tests positive, what is next?

When a person tests positive in Michigan, several things begin to happen right away. First, your name is reported to your local health department, who then dispatches a case worker to meet with you. The worker's job is to assist you in contacting the sexual and needle sharing partners you have had in the past year. Some departments try to tell HIV infected persons they have to tell every sexual partner they have ever had, but the law in Michigan says only in the last year (for single people). You are not required to provide names of sexual contacts to the case worker, although they will push you for them. The law says the department has to help you if you WANT the assistance. Your name and HIV tests are then forwarded to the state department of community health.

In addition to the health department, a person is also connected with an infectious disease specialist and a series of blood tests are run.

In my case, the following tests were conducted when I tested positive:

HIV Genotype
HIV Viral Load
HIV PCR
Full blood panel
Absolute CD4 count
Liver function
Syphilis
TB
Toxoplasmosis
Cytomeglavirus
Hepatitus screening

In my case, that first blood draw order was a bit overwhelming. First it was a fasting draw, secondly the tests listed above amounted to about 20 vials of blood (at least that is what my mind recalls). It did not help that the hospital that did the blood draw for the testing mislabeled the HIV specific tests thus giving me more HIV antibody results. Yes, it's true. I was tested for antibodies 6 times within four weeks due to a lab technician's error.

What does each test mean and why do they test you for it?

HIV Genotype This test looks at the genetic markers of the virus and compares them with known genetic variants which cause viral immunity to the various classes of drugs used to fight HIV.
HIV Viral Load Measuring the number of virus in a milliliter of blood, this test literally counts the number, with a value of measurement between 48 and 1,000,000 virus particles/ml.
HIV PCR This is a test using a genetic testing technique called Pommerase Chain Reaction-- PCR. The test breaks genetic material into bands, and by comparing the test with persons who are not infected with HIV, the test can determine the presence of HIV genes.
Full blood panel This set of tests looks at all of your body functions and give the doctor treating you a baseline to compare future tests with. Particularly important are tests for Cholesterol, liver functions, blood sugar and blood counts. These tests are important because they can be used to determine the impact of HIV medications on the body. Many of them can damage the liver or pancreas, and at least one causes potentially dangerous spikes in Cholesterol and has been linked to heart attacks.
Absolute CD4 count This measures the number of CD4 blood cells in your blood. A normal blood count is 800-1,200. Anything over 500 for an HIV positive person is considered excellent. The Centers for Disease Control now recommends beginning treatment with antiretroviral medications when CD4 counts reach 350. A clinical diagnosis of AIDS can be made when a person has a CD4 count of 200 or less. The lower the count, the more at risk of getting sick a person is.
Liver function This looks at the blood levels of various chemicals tied to the liver function. This is important because it can show when and if medications are impacted the liver, or if co-infection with a Hepatitis virus might be an issue.
Syphilis This is a blood test which looks for the bacteria which causes the dreaded disease. Many people who are infected with HIV, are also co-infected with this treatable bacterial infection, but may have no symptoms. The bacteria causes a three stage disease process, starting with small ulcers which are painless, and go away on their own. About three weeks after that, a rash appears on the body, and this too goes away. The final stage, the bacteria infects internal organs, including the nervous system, and can cause death. Obviously, a person who is immune compromised is likely to get sicker faster than those who are not.
TB Once a nearly wiped out disease, TB or Tuberculosis is caused by a micobacterium. It is spread through body fluids, and can be spread from casual contact, including breathing in the infected vapors of another person. Since HIV has hit the homeless and intravenous populations in the U.S. TB has also resurged, and now comes in a dangerous antibiotic resistant form. It is now considered a major opportunistic infection of those with HIV.
Toxoplasmosis This is a bacteria found most commonly in soil around the house or in the cat litter box. Pregnant women are warned not to handle soiled litter for fear of infection with this bacteria, which can cause still births. In immune compromised persons, the bacteria can attack any number of internal organs, leading to death. It is a common opportunistic infection in Michigan's HIV positive community.
Cytomeglavirus CMV is a herpes virus which has infected 98 percent of the adult American population. It can cause mono like symptoms in healthy people, but for those who are immune compromised it can cause blindness, pnuemonia and gastrointestinal problems. The labs run two test, one is an antibody test for CMV, the second is a test for the core of the virus. A more sensitive test called a titer can be run, which will tell you how active the virus is in your blood.
Hepatitis screening This panel tests for the three major Hepatitis viruses, A, B and C. Hepatitis A causes an acute illness, and once the symptoms subside a person is considered immune to reinfection. Rarely, a person who has had Hep. A. will test as if they are currently actively infected with the virus. Hepatitis B is a viral infection which attacks the liver. In 95 percent of cases, the virus is cleared by the body without incident. However, 5 percent of those exposed to Hepatitis B will go one to develop long term disease, which leads to cancer and eventually liver failure. There is a vaccine for Hep. B. Hepatitis C is a virus which once a person has it, does not go away. It causes acute liver failure, liver disease and cancer. It is a common co-infection with HIV, and is currently epidemic in Michigan's prison system. About 1.6% of the population is infected with Hep. C, and many who have it do not know it.

My test results

Since some of our blog readers appear to be quite ignorant on the issue of HIV infection, and disease progression, I thought I would share my personal results.

I am pleased to report I don't have Toxo, Syphilis, TB, or Hepatitis. I am one of the people who tests positive as if I have an active Hep. A infection, but I had the joy of that infection in summer 1996. I am vaccinated against Hep. B. and I have immunity. I have CMV, (as do about 98% of American adults, btw) however it is not currently an active infection.

My viral load was undetectable in July and again in February. That means there were less than 48 viral particles per ml of my blood. In April, my viral load had a small blip, rising to 130.

My CD4 count was 520 in February, in April it was 483.

Each of those counts could be effected by the time of day the blood was drawn, stress levels and other issues like allergies.

So in short, sorry to disappoint those who might wish otherwise, but I am quite healthy and not heading anywhere soon.