The purpose of this study is:

1. To assess the validity and reproducibility of the MP Diagnostics HTLV Blot 2.4.
2. To conduct a sensitivity analysis of the HTLV Blot 2.4 using a known positive population.

This is a retrospective study designed to assess the validity and reproducibility of the MP Diagnostics IVD device, the HTLV Blot 2.4 (MP Blot), in various populations. The study will be conducted at three geographical distinct locations.

The validity of the MP Blot will be assessed by calculating the following:

1. Percent negative agreement with CDPHL Algorithm on 200 EIA negative specimens
2. Percent positive agreement with CDPHL Algorithm on 200 EIA repeat reactive specimens

The sensitivity of the MP Blot will be evaluated by testing 200 known positive specimens. The study will be performed using three product lots at three clinical sites.

The reproducibility of the MP Blot will be assessed by testing two replicates of a three member panel at three clinical testing sites with each of three lots of product over multiple days by three operators.

Inclusion Criteria:

• EIA Negative Population

  1. Male or female
  2. Completion of a health history evaluation for routine donor screening
  3. Willing and able to provide informed consent
  4. Negative screening assay results for all ARC screening assays

• EIA Repeat Reactive Population

  1. Male or female
  2. Completion of a health history evaluation for routine donor screening
  3. Willing and able to provide informed consent
  4. Previous RR result by bioMerieux ELISA, Abbott EIA, and / or Abbott ChLIA PRISM

• Known Positive Population

  1. Male or female
  2. Willing and able to provide informed consent
  3. Previous reactive screening test using either the bioMerieux ELISA, the Abbott EIA or the Abbott ChLIA PRISM, followed by supplemental testing

Exclusion Criteria:

• EIA Negative Population

  1. Inadequate sample volume for testing
  2. Unable to provide samples that meet the sample suitability requirements for testing
  3. Positive screening result for any infectious disease tested by ARC

• EIA Repeat Reactive Population

  1. Inadequate sample volume for testing
  2. Unable to provide samples that meet the sample suitability requirements for testing
  3. Positive result for HIV, HBV, HCV, or any other infectious disease

• Known Positive Population

  1. Unwilling or unable to provide informed consent
  2. Unable to provide adequate sample volume for testing
  3. Unable to provide samples that meet the sample suitability requirements for testing
  4. Positive result for HIV

All populations are from whole blood donors.