Roche claims to be 99.997% accurate??? - TheBody.com's Bulletin Boards

The following is directly taken from the Johns Hopkins Medical Management of HIV under HIV Serologic Test section.

The link is

http://www.hopkins-aids.edu/publications/book/ch2_1_alternative.html#alt

Viral Detection: Other methods to establish HIV infection include techniques to detect HIV antigen, DNA, or RNA (Table 2-1). HIV-1 DNA PCR is the most sensitive and can detect 1-10 copies of HIV proviral DNA. None of these tests is considered superior to routine serology in terms of accuracy, but some may be useful in patients with confusing serologic test results, when there is a need to clarify indeterminate test results, for virologic monitoring in therapeutic trials, and for HIV detection when routine serologic tests are likely to be misleading such as in patients with agammaglobulinemia, acute retroviral infection, neonatal HIV infection, and patients in the window following viral exposure. In most cases, confirmation of positive serology is accomplished simply by repeat serology. The sensitivity of tests for detection of HIV varies with the stage of disease and test technique, but is usually reported at >99% for DNA-PCR, 90% to 95% for quantitative HIV-RNA, 95% to 100% for viral culture of peripheral blood mononuclear cells (PBMC), and 8% to 32% for p24 antigen detection (J Clin Microbiol 1993;31:2557; N Engl J Med 1989;321:1621; J AIDS 1990;3:1059; J Infect Dis 1994;170:553; Ann Intern Med 1996;124:803). None of these tests should replace serology to circumvent the informed consent process.

Table 2-1: Tests for HIV-1
Assay Sensitivity Comments
Routine
serology 99.7% Readily available and inexpensive. Sensitivity and specificity >99.9% (MMWR 1990;39:380; N Engl J Med 1988;319:961; JAMA 1991;266:2861).
Rapid test
SUDS [Murex
Diagnostics, Norcross, Ga.] 99.9% Results are available in <10 minutes but test must be performed by a lab technician. Specificity is 99.6%; positive tests should be confirmed. Highly sensitive; negative tests do not usually require confirmation. Other rapid tests are available but are not FDA approved (Int J STD AIDS 1997;8:192; Vox Sang 1997;72:11).
Salivary test
(OraSure Test System) 99.9% Salivary collection device to collect lgG for EIA and WB. Advantage is avoidance of phlebotomy. Sensitivity and specificity are comparable to standard serology (JAMA 1997;227:254).
Urine test (Calypte 1) >99.9% Used for EIA test only, so positive results must be verified by serology. Must be administered by a physician. Cost is low - about $4/test.
PBMC culture 95% to 100% Viral isolation by co-cultivation of patient's PBMC with phytohemagglutinin (PHA)-stimulated donor PBMC with IL-2 over 28 days. Expensive and labor-intensive. May be qualitative or quantitative. Main use of qualitative technique is viral isolation for further analysis and for HIV detection in infants. Quantitative results correlate with stage: Mean titer is 20/106 cells in asymptomatic patients and 2,200/106 cells in patients with AIDS (N Engl J Med 1989;321:1621).
DNA PCR assay >99% Qualitative DNA PCR is used to detect cell- associated proviral DNA; primers are commercially available from Roche Laboratories. Sensitivity is >99% and and specificity is 98%. This is not considered sufficiently accurate for diagnosis without confimation and is not FDA-approved (Ann Intern Med 1996;124:803). Main use is for viral detection in the case of neonatal HIVand disputed or indeterminate serologic tests.

HIV RNA PCR 95% to 98% False-positive tests in 2% to 9%; usually at low titer. Sensitivity depends on viral load (VL) threshold of assay and assumes no antiretroviral therapy.

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