Update on Thermo Fisher TaqPath


On August 17, 2020 the US Food and Drug Administration (FDA) issued a warning related to the Thermo Fisher Taqpath kit that is used for COVID-19 RT-PCR testing. This test is widely used across the US, including here at US BioTek Laboratories.

The concerns raised in the FDA warning do not affect any US BioTek test results. You can remain confident in the accuracy of any COVID-19 Diagnostic Test results you have received, or have yet to receive, from us.

There are two issues mentioned in the letter from FDA: the potential for inadequate mixing during the sample preparation and a required software update.

Mixing Protocol

On July 15, 2020 Thermo Fisher had a “Version F” update where they removed a manual mixing procedure in the preparation stage and added instructions to vortex the RT-PCR plates to ensure proper mixing. The “Version F” also included updated centrifuge and sealing instructions when preparing the RT-PCR plates.


This issue was identified by our team during the validation process of our assay, and was resolved by incorporating an automated vortexer/centrifuge in place of the manual mixing procedure. The system has ensured thorough mixing and consistent results since we first started performing the test in May. Due to our diligent quality processes and strive towards the most accurate testing possible, this issue never affected any testing performed at US BioTek.


Software Update

The software update changes the setting of internal control that is added to every test. The algorithm update in the software improves the accuracy of internal control detection to reduce the frequency of invalid or inconclusive tests and decrease the retest burden on laboratories. Analysis settings for COVID-19 virus targets have not been changed. It is called an emergency update although the changes are not directly related to the detection of the virus itself.


US BioTek received and installed the update on July 31, 2020. This software update does not affect the accuracy of results reported prior to the update.



We hope that our proactive actions have not only eased your concerns, but serve to highlight our commitment to quality. If you have any questions, please reach out to our team at info@usbiotek.com or 206.365.1256.

Frequently Asked Questions

Does the FDA warning affect test results?

No, this FDA warning does not affect any US BioTek test results. We took proactive steps when validating our Thermo Fisher Taqpath assay to ensure the the mixing step of preparation would lead to accurate and consistent results. Similarly, we installed the software update on July 31, 2020, and this update does not affect the quality of our previously reported results.

Where can I view the FDA warning letter?

You can view the FDA warning on their website.

How does US BioTek ensure accurate results?

Accurate and consistent test results are of the utmost importance to us. We follow our rigorous VeriTek™ quality assurance process to consistently deliver the accurate, repeatable results you and your patients expect and deserve from a laboratory partner. VeriTek™ employs advanced automated technology, and superior assay preparation, with accreditation from CLIA and COLA to ensure protocols that exceed industry standards.