I would like to make a test, just so that I know. I don't think that I have it as I have been careful, most of the times, and that's the reason..."most of the times" not "every time".
I am very scared of results... and the waiting time.
I know it is the right thing to do, I just can't take the mental strain. take it from someone who has beent here,
it is very very scarey to wait, and even worse to wonder.
try to push your feelings aside and think about life,
the sooner you get yourself together, the sooner you will know.
and you have to think about EVERY aspect of this test,
if it is positive, then the sooner you take the test, the sooner you will know, and you can have treatment.
sorry if i couldnt help, and i hope everything goes ok. Is the mental strain of wondering less than the mental strain of knowing? That is really up to you. The fda just legalized an at-home test, should be quicker, (but less accurate.) It's better to know than to worry all the time for nothing. Tut tut who's been a naughty girl?. Best you get it checked in case you go spreading it around even more. Before I got married I had the test every time I ended or started a relationship just to be on the safe side, anyone potential boyfriend had to have one also I would still still do so now if I was single.
It's my life and why the hell take chances with it HIV (Human Immunodeficiency Virus) test kits used both to screen donor blood, blood components and cellular products, and to diagnose, treat and monitor persons with HIV and Acquired Immuno Deficiency Syndrome (AIDS) are regulated in the United States by the Food and Drug Administration (FDA).
HIV tests to detect antibodies, antigens or ribonucleic acid (RNA) in serum, plasma, oral fluid, dried blood spot or urine have been approved by FDA for donor screening, diagnosis, prognosis and patient monitoring.
Contents [hide]
1 Terminology
2 Principles
2.1 Screening donor blood and cellular products
2.2 Diagnosis of HIV infection
2.3 Human Rights
3 Antibody tests
3.1 ELISA
3.2 Western blot
3.3 Rapid or point-of-care tests
3.4 Interpreting antibody tests
4 Antigen tests
5 Nucleic acid based tests (NAT)
6 Other tests used in HIV/AIDS treatment
7 Criticisms of HIV tests
8 Notes
9 External links
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Terminology
The window period is the time from infection until a test can detect any change. The average window period with antibody tests is 22 days. Antigen testing cuts the window period to approximately 16 days and NAT further reduces this period to 12 days. FDA 2001
Antibody tests are reported as positive or negative. Performance of these tests is described in terms of:
sensitivity: The percentage of the results that will be positive when HIV is present
specificity: The percentage of the results that will be negative when HIV not present.
All diagnostic tests have limitations, and sometimes their use may produce erroneous or questionable results.
False positive results indicate that HIV is found to be present when, in fact, it is not.
False negative results do not identify HIV that is present.
Nonspecific reactions, hypergammaglobulinemia, or the presence of antibodies directed to other infectious agents that may be antigenically similar to HIV can produce false positive results. Autoimmune diseases, such as systemic lupus erythematosus, can also cause false positive results.
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Principles
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Screening donor blood and cellular products
Tests selected to screen donor blood, blood components and cellular products provide a high degree of confidence that HIV is not present. A combination of antibody, antigen and nucleic acid tests are used by blood banks in Western countries. The WHO estimated that in 2000 inadequate blood screening in some countries resulted in 1 million new HIV infections.
In the USA, most blood donations are screened with an ELISA test for HIV 1/2 and a nucleic acid test. Combined with careful donor selection, the HIV risk in the USA for 2001 was approximately one in 2.5 million for each transfusion[1].
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Diagnosis of HIV infection
Different tests are selected for the diagnosis of HIV infection in a particular person, which requires a high degree of confidence that HIV is present. In the United States, this is achieved by an algorithm using two tests to detect antibodies, which are the body鈥檚 response to infection. If antibodies are detected by an initial test based on the ELISA method, then a second test based on the Western blot procedure determines the size of the antigens in the test kit binding to the antibodies. According to the CDC, there are 1.1 million persons infected with HIV in the United States as of 2005.
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Human Rights
The UNAIDS/WHO policy statement on HIV Testing (PDF) states that conditions under which people undergo HIV testing must be anchored in a human rights approach, which pays due respect for ethical principles. According to these principles, the conduct of HIV testing of individuals must be:
confidential
accompanied by counselling
conducted with informed consent, meaning both informed and voluntary
The reality is that stigma and discrimination continue to stop people, who may have been exposed to HIV infection, from consenting to HIV testing.
HIV testing and counselling has a pivotal role in preventing HIV infection around the world.
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Antibody tests
Antibody tests are specifically designed for the routine testing of HIV in adults, are inexpensive, and are very accurate.
Antibody tests give false negative results during the window period of between three weeks and six months from the time of HIV infection until the immune system produces detectable amounts of antibodies. The vast majority of people have detectable antibodies after three months. A six month window is extremely rare with modern antibody testing. During this window period an infected person can transmit HIV to others, without their HIV infection being detectable using an antibody test. Antiretroviral therapy during the window period can delay the formation of antibodies and extend the window period beyond 12 months. C B Hare, B L Pappalardo, M P Busch, B Phelps, S S Alexander, C Ramstead, J A Levy, F M Hecht (2004). "Negative HIV antibody test results among individuals treated with antiretroviral therapy (ART) during acute/early infection". The XV International AIDS Conference, Abstract no. MoPeB3107. Antibody tests also give false negative results for X-linked agammaglobulinemia patients, and other diagnostics should be used with them.
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ELISA
The ELISA test, or the enzyme immunoassay (EIA), was the first screening test commonly employed. It has a high sensitivity.
The test proceeds by the general ELISA method: the person's serum is diluted 400 fold and applied to a plate to which HIV antigens have been attached. Some of the antibodies in the serum may bind to these HIV antigens. The plate is then washed to remove all other components of the serum. Then a specially prepared "secondary antibody"鈥攁n antibody that binds to human antibodies鈥攊s applied to the plate, followed by washes. This secondary antibody is chemically linked in advance to an enzyme. Thus the plate will contain enzyme in proportion to the amount of secondary antibody bound to the plate. A substrate for the enzyme is applied, and catalysis by the enzyme leads to a change in color or fluorescence. As the ELISA results are reported as a number, the most controversial aspect of this test is deciding the "cut off" point between positive and negative.
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Western blot
The Western blot test uses the general Western blot procedure. HIV-infected cells are opened and the contained proteins are entered into a slab of gel to which a voltage is applied. Different proteins will move with different velocities in this field, depending on their size, while their electrical charge is levelled by a substance, called sodium lauryl sulfate. Once the proteins are well separated, they are transferred to a membrane and the procedure continues similar to ELISA: the person's diluted serum is applied to the membrane and antibodies in the serum may attach to some of the HIV proteins. Antibodies which do not attach are washed away, and enzyme-linked antibodies with the capability to attach to the person's antibodies first detect to which HIV proteins the person has antibodies.
There is no universal criteria for interpreting the Western blot test: the number of viral bands which must be present vary from definition to definition. If no viral bands are detected, the result is negative. If at least one viral band for each of the GAG, POL, and ENV gene-product groups are present, the result is positive. Thus the three-gene-product approach to Western blot interpretation has not been adopted for public health or clinical practice. Tests in which less than the required number of viral bands are detected are reported as indeterminate: a person who has an indeterminate result should be retested, as later tests may be more conclusive. Almost all HIV-infected persons with indeterminate Western-Blot results will develop a positive result when tested in one month; persistently indeterminate results over a period of six months suggests the results are not due to HIV infection.
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Rapid or point-of-care tests
Rapid Antibody Tests are qualitative immunoassays intended for use as a point-of-care test to aid in the diagnosis of HIV infection. These tests should be used in conjunction with the clinical status, history, and risk factors of the person being tested. The specificity of Rapid Antibody Tests in low-risk populations has not been evaluated. These tests should be used in appropriate multi-test algorithms designed for statistical validation of rapid HIV test results.
If no antibodies to HIV are detected, this does not mean the person has not been infected with HIV. It may take several months after HIV infection for the antibody response to reach detectable levels, during which time rapid testing for antibodies to HIV will not be indicative of true infection status. A comprehensive risk history and clinical judgement should be considered before concluding that an individual is not infected with HIV.
OraQuick is an antibody test that provides results in 20 minutes. The blood, plasma or oral fluid is mixed in a vial with developing solution, and the results are read from a sticklike testing device.
Orasure is an HIV test which uses mucosal transudate from the tissues of cheeks and gums. It is an antibody test which first employs ELISA, then Western Blot.
There is also a urine test; it employs both the ELISA and the Western Blot method.
Home Access Express HIV-1 Test is a FDA-approved home test: the patient collects a drop of blood and mails the sample to a laboratory; the results are obtained over the phone.
There have been a number of cases of fraudulent tests being sold via mail order or the Internet to the general public. In 1997, a California man was indicted on mail fraud and wire charges for selling supposed home test kits. In 2004, the US Federal Trade Commission asked Federal Express and US Customs to confiscate shipments of the Discreet home HIV test kits, produced by Gregory Stephen Wong of Vancouver, BC. In February 2005, the US FDA issued a warning against using the rapid HIV test kits and other home use kits marketed by Globus Media of Montreal Canada.
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Interpreting antibody tests
ELISA testing alone cannot be used to diagnose HIV, even if the recommended investigation of reactive specimens suggests a high probability that the antibody to HIV 1 is present. In the United States, such positive tests are not reported out unless confirmed by a Western Blot test.
The ELISA antibody tests were developed to provide a high level of confidence that donated blood was NOT infected with HIV. It is therefore not possible to conclude that blood rejected for transfusion because of a positive ELISA antibody test is in fact infected with HIV. Sometimes, retesting the donor in several months will produce a negative ELISA antibody test. This is why a confirmatory Western Blot is always used before reporting HIV status.
False positive results due to factors unrelated to exposure to HIV are found more often with the ELISA test than with the Western Blot. False positives can be caused by antibodies to viruses other than HIV, antibodies produced by pregnancy, and other medical conditions. A false positive results DOES NOT indicate that you are infected with HIV, nor does it indicate a condition of significant risk to your health. When the ELISA test is combined with Western Blot, the rate of false positives is extremely low (less than 0.1%).
The evidence for regarding the risks and benefits of HIV screening was reviewed in July 2005. ("Screening for HIV: A Review of the Evidence for the U.S. Preventive Services Task Force", Annals of Internal Medicine, Chou et. al, Volume 143 Issue 1, pp. 55-73. [2]): "The use of repeatedly reactive enzyme immunoassay followed by confirmatory Western blot or immunofluorescent assay remains the standard method for diagnosing HIV-1 infection. A large study of HIV testing in 752 U.S. laboratories reported a sensitivity of 99.7% and specificity of 98.5% for enzyme immunoassay, and studies in U.S. blood donors reported specificities of 99.8% and greater than 99.99%. With confirmatory Western blot, the chance of a false-positive identification in a low-prevalence setting is about 1 in 250 000 (95% CI, 1 in 173 000 to 1 in 379 000)."
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Antigen tests
The p24 antigen test detects the presence of the p24 protein of HIV (also known as CA), a major core protein of the virus. Monoclonal antibodies specific to the p24 protein are mixed with the person's blood. Any p24 protein in the person's blood will stick to the monoclonal antibody and enzyme-linked antibody to the monoclonal antibodies to p24 causes a color change if p24 was present in the sample.
This test is no longer used routinely in the US[3] or the EU [4] to screen blood donations since the objective was to reduce the risk of false negatives in the window period. Nucleic acid testing (NAT) is more effective for this purpose, and p24 antigen testing is no longer indicated if a NAT test is performed. The p24 antigen test is not useful for general diagnostics, as it has very low sensitivity and only works during a certain time period after infection before the body produces antibodies to the p24 protein.
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Nucleic acid based tests (NAT)
Nucleic acid based tests amplify and detect a 142 base target sequence located in a highly conserved region of the HIV gag gene. Since 2001, donated blood in the United States, has been screened with nucleic acid based tests, shortening the window to about 12 days. Since these tests are relatively expensive, the blood is screened by first pooling some 10-20 samples, testing these together, and if the pool tests positive, each sample is retested individually. A different version of this test is intended for use in conjunction with clinical presentation and other laboratory markers of disease progress for the clinical management of HIV-1 infected patients.
In the RT-PCR test, the viral RNA is extracted from the patient's plasma and is treated with reverse transcriptase so that the RNA of the virus is transcribed into DNA. The polymerase chain reaction (PCR) is applied, using two primers thought to be unique to the virus's genome. After the PCR amplification process is completed, which takes some time, the resulting amplified segments bind to specific oligonucleotides bound to the vessel wall and are then made visible with a probe that's bound to an enzyme. The amount of virus in the sample can be quantified with sufficient accuracy to detect three fold changes.
In the Quantiplex bDNA or branched DNA test plasma is centrifugated to concentrate the viruses, which are then opened to release the RNA. Special oligonucleotides are added which bind to viral RNA and to certain oligonucleotides bound to the wall of the vessel. In this way, viral RNA is fastened to the wall. Then new oligonucleotides are added which bind at several locations to this RNA; and other oligonucelotides which bind at several locations to those oligonucleotides. This is done to amplify the signal. Finally, oligonucleotides that bind to the last set of oligonucleotides and that are bound to an enzyme are added; the enzyme action causes a color reaction which allows to quantify the viral RNA in the original sample. Monitoring the effects of antiretroviral therapy by serial measurements of plasma HIV-1 RNA with this test has been validated for patients with viral loads greater than 25,000 copies per millilitre. reference
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Other tests used in HIV/AIDS treatment
The CD4 T-cell count is not an HIV test, but rather a procedure where the number of CD4 T-cells in one microlitre of blood are counted in a standard medical lab test after a blood draw.
This test does not check for the presence of HIV. It is used monitor the immune system function in HIV+ people. Declining CD4 T-cell counts are considered to be a marker of the progression of HIV infection. In HIV+ people, AIDS is officially diagnosed when the count drops below 200 cells or when certain opportunistic infections occur. This use of a CD4 count as an AIDS criterion occurred in 1992; the value of 200 was chosen because it corresponded with an increased likelihood of opportunistic infections. Lower levels of CD4 counts in people with AIDS are indicators that prophylaxis against certain types of opportunistic infections should be instituted.
Low CD4 T-cell counts are associated with a variety of conditions, including many viral infections, bacterial infections, parasitic infections, sepsis, tuberculosis, coccidioidomycosis, burns, trauma, intravenous injections of foreign proteins, malnutrition, over-exercising, pregnancy, normal daily variation, psychological stress, and social isolation.
This test is also used occasionally to estimate immune system function for people whose CD4 T cells are impaired for reasons other than HIV infection, which include several blood diseases, several genetic disorders, and the side effects of many chemotherapy drugs.
Generally speaking, the lower the number of T cells, the lower the immune system's function will be. Normal T4 counts are between 500 and 1500 CD4+ T cells per microliter and the counts may fluctuate in healthy people, depending on recent infection status, nutrition, exercise and other factors -- even the time of day. Women tend to have somewhat lower counts than men.
Symptoms of T4 cell immune collapse are almost never seen until the number drops below 200. Similar symptoms of immune collapse are generally seen in people with very low T4 cell counts, whether this immunosuppression is caused by HIV, cancer, or some other disease. However, the long-term treatment differs substantially, because it needs to address the cause of the immunosuppression.
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Criticisms of HIV tests
Criticisms of HIV tests have been made by a number of so-called "AIDS dissidents" (people who question the theory that HIV causes AIDS). Eleni Papadopulos-Eleopulos and a group of AIDS dissidents published an article in Bio/technology in 1993: Is a Western Blot Proof of HIV Infection? Their arguments rest on alleged non-specificity of HIV proteins and lack of standardisation and reproducibility of HIV tests. The authors state, "It is axiomatic that the use of antibody tests must be verified against a gold standard. The presently available data fail to provide such a gold standard for the HIV antibody tests. The inescapable conclusion from the above discussion is that the use of HIV antibody tests as predictive, diagnostic and epidemiological tools for HIV infection needs to be carefully reappraised."
However, the accuracy of serologic testing has in fact been verified by isolation and culture of HIV and by detection of HIV RNA by PCR; these are widely accepted "gold standards" in microbiology.[1][2]
The vast majority of scientists believe that the view of AIDS dissidents are based on highly selective analysis of mostly outdated scientific papers. AIDS dissident arguments are widely regarded as pseudoscience.[5]
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Notes
^ Busch M, Eble B, Khayam-Bashi H, Heilbron D, Murphy E, Kwok S, Sninsky J, Perkins H, Vyas G (1991). "Evaluation of screened blood donations for human immunodeficiency virus type 1 infection by culture and DNA amplification of pooled cells.". N Engl J Med 325 (1): 1-5. PMID 2046708.
^ MacDonald K, Jackson J, Bowman R, Polesky H, Rhame F, Balfour H, Osterholm M (1989). "Performance characteristics of serologic tests for human immunodeficiency virus type 1 (HIV-1) antibody among Minnesota blood donors. Public health and clinical
try to visit this site :
http://www.aids.org/info/testing.html I know this is a really scary time for you, should i? shouldnt i?. Is ignorance bliss? I never wanted to be tested and then i had to cause when i was in the hospital after childbirth of first son, a girl that draws the blood stuck herself with the needle she used on me. Auto matically i get tested. ugh, everything was fine and i was like you, problaby not but ?? . You need to know your health status so you can stay healthy. The mental strain is short lived, dont worry, its actually less than all this worrying. lol. Just do it and get your answer that you obviously want to know. HUGS Tracey there are no worries as long as you are sure you don't have it then you probably don't so don't get so worked up about it!
i got tested also and i was also nervous about what my outcome would be, even know i was almost positive i didn't have it. everything turned out good for me though.
i wish you the best of luck also! :) If you don't take the test you'll never know and it will probably never be far from your mind - that's surely more strain than taking the test? You'll know before too long.
If the test is positive you probably ought to know.
If the test is negative, you can get on with your life safe in the knowledge that you are NOT hiv positive, the worry will be over and a great weight lifted from your shoulders - and then you can practice safe sex for ever more so that you never find yourself in this predicament again!! im sure your mom would be proud if you have any doubts this is the time to get urself tested before it turns into aids if you hae it .ppl can live a number of years treating hiv before it turns into full blown aids and if you are negitive you would be smarter to take the time to ask the guy to use a condom when you have sex dont be scared.. i got 2 HIV tests.. first one before i got marry (is a law in my country thet you have to get tested before you got marry both you and Ur partner) i waited 5 hours to get results.all was fine but i scared too. 2. one when i was pregnant .. one of the routin pregnancy tests..it was fine too. but its really scary waiting. but when you get your good result you will feel like you were just born!what a relief..just get test and put your mind in rest. you just gotta go and do it.its as simple as that..god bless.xx It's normal to feel scared. Try to remeber that you will most likely be fine, and once you know you can stop worrying. Plus, if are positive, it is much better for your physical health to know sooner and for your mental health it would also be better. Just think of how devestating it would be to not check and then to find out in a few years that you have been HIV + for a while, and that you passed the virus on to person(s) you care about.
Whatever the situation, I think that you will feel better for taking the resposible steps to get tested. Really. Just know that you are not alone. |
