COVID-19 Omicron Variant

ADx Health and Northwest Laboratory have been at the forefront of COVID-19 testing since the inception of the pandemic and have performed over 2 million COVID-19 RT-PCR tests to date.

As an organization, we are aware that the topic of COVID variants has become of concern, and we will continue to service our clients, community, and the general public with COVID-19 testing that includes detection of the Omicron Variant.

We perform RT-PCR testing for SARS-CoV-2 that detects signals from 3 different SARS-CoV-2 genes (S, N, and orf1a/b).

  • The Omicron variant has a mutation in the S gene that causes the gene signal to be lost.  However, the remaining two gene signals are still present. This is called SGTF (S gene target failure) or S gene dropout.
  • An RT-PCR test result which shows the remaining two gene signals, but not the S gene signal, is a positive result that is highly likely to be Omicron based on our knowledge at this time (the same situation was noted for the alpha variant [UK Variant], which also has an S gene mutation).
  • RT-PCR is routinely performed for all SARS-CoV-2 RT-PCR testing offered by ADx Health and performed by Northwest Laboratory and provides a rapid ability to detect specimens that are likely to be Omicron. 
  • Northwest Laboratory will not report the presence of a specific variant; only whether the sample is positive or negative for SARS-CoV2. 
  • Positive SGTF specimens will be sent to the Washington State Department of Health Laboratory for whole genome sequencing and variant identification.  

With the emergence of any new variant, we advise the public to follow CDC recommendations on how to protect themselves and others.

For scheduling, results, or general questions related to COVID-19 testing, please contact our Customer Service Team at or by calling 360-527-4592.

The Customer Service Team is available Mon-Fri: 7am-10pm; Sat & Sun 8am-10pm PST.

About Our Testing

All testing is performed at Northwest Laboratory, a full-service, CLIA-certified, and CAP-accredited laboratory located in Bellingham, WA.