SENSITIVITY AND SPECIFICITY"At present there is no recognised standard for establishing the presence or absence of antibodies to HIV1 and HIV2 in human blood."SEE ACTUAL LABEL AT: -http://groups.msn.com/testing-testing-te...
Answer:
Dear Actuot,The label pictured in the link provided with this question is from the 994: AxSYM HBsAg* test.I have seen it myself.I checked your links to Abbott and find you were very selective in your quotes and selected only those to your liking.No mention of this, for example."However, as for all enzyme immunoassays, AxSYM HIV Ag/Ab Combo may yield nonspecific reactions due to other causes, particularly when testing in low prevalence populations.human plasma (inactivated), is reactive for anti-HIV-1 and nonreactive for HBsAg, HIV-1 Ag, and anti-HCV. The HIV-2 Positive Control (PC2), prepared in recalcified "
also from your link"• The presence of HIV-1/HIV-2 antibodies and/or HIV p24 antigen is not a diagnosis of AIDS.(True negative specimens + False positive specimens) "
Well, I went to Abbott's website and it turns out the Axsym test is not available in the US. http://www.abbottdiagnostics.com/about_u...So I went to the UK version and looked up the label there: http://www.abbottdiagnostics.co.uk/getpd...And oddly enough, it doesn't contain that quote anywhere in it.It does say:"Acquired immunodeficiency syndrome (AIDS) is caused by two types of human immunodeficiency viruses, collectively designated HIV.1-7 HIV is the etiologic agent of AIDS.1,3,6,7 HIV is transmitted by sexual contact, exposure to blood or blood products, and prenatal or perinatal infection of a fetus or newborn, respectively.8 Antibodies against HIV are nearly always detected in AIDS patients and HIV infected asymptomatic individuals,8,9 and HIV nucleic acid (RNA and/or proviral DNA) is always detected in AIDS patients and seropositive individuals.8,10"Care to explain? Where exactly is that label from, and can you provide a link to the original PDF?
"bobscottreturns" - HBsAg stands for hepatitis B surface antigen.And sure, I provided the link so that nobody could read that...Of course it's not used to diagnose AIDS, it's for HIV infection. There are a lot of Q%26As on YA about the difference between the two, you could perhaps look them up.Oh, and I looked up the Axsym label for the hepatits B surface antigen and couldn't find the phrase there, either:http://www.abbottdiagnostics.com/getpdf.windy - are you suggesting that Abbott's manufacturing difficulties extend to the print on their labels?-----Please note "bobscottreturns" quote from the testing label, below. It is a truly classic example of denialist behavior. He has taken part of this paragraph:"Specimens that are initially reactive in the AxSYM HIV Ag/Ab Combo MEIA should be retested in duplicate. Repeat reactivity is highly predictive of the presence of HIV-1 and/or HIV-2 antibodies and/or HIV p24 antigen. However, as for all enzyme immunoassays, AxSYM HIV Ag/Ab Combo may yield nonspecific reactions due to other causes, particularly when testing in low prevalence populations. A repeatedly reactive specimen should be investigated further in sensitive, supplemental HIV specific tests, such as immunoblots, antigen tests, and HIV nucleic acid tests. Supplemental testing of repeat reactive specimens obtained from individuals at risk for HIV infection usually confirms the presence of HIV antibodies or HIV antigen, and HIV nucleic acid. A full differential diagnostic work-up for the diagnosis of AIDS and AIDS-related conditions includes an examination of the patient’s immune status and a clinical history."And glommed it together with some text from a different section about using positive controls:"The HIV-1 Positive Control (PC1), prepared in recalcified human plasma (inactivated), is reactive for anti-HIV-1 and nonreactive for HBsAg, HIV-1 Ag, and anti-HCV."http://www.abbottdiagnostics.co.uk/getpd..."espresso first" - those are *rapid tests,* which require confirmation. Thanks for actually posting the links though, there is informative data in them. Any idea which label the phrase in this question ("At present there is no recognised standard for establishing the presence or absence of antibodies to HIV1 and HIV2 in human blood.") comes from? Can you find that label?
With all the hoopla by test manufacturers that the tests are like 99.9 % what seems to be an easy way out for these test makers is an apparent noncommittal to what they actually purport. Words like “PRESUMED,” “SUGGESTS” and “INTENDED AS AN AID” are found right in their own LABLES as follows:Multispot Hiv-1/HIV-2 Rapid Test
12. Limitations.
10. A person who has antibodies to HIV-1 is presumed to be infected with the virus..
Bio-Rad Laboratories, Redmond, WashingtonOraQuick
Limitations.
6. A reactive result using the OraQuick Advance Rapid HIV-1/2 Antibody Test suggests the presence of HIV-1 and/or HIV-2 Antibodies in the specimen. The OraQuick Advance Rapid HIV-1/2 Antibody Test is intended as an aid in the diagnosis of infection with HIV-1 and/or HIV-2.
OraSure Technologies, Bethlehem, Pennsylvania Seek and you shall find!
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