HomeMy WebLinkAbout02012021_Schumacher_PCR Testing_ResponseFrom:Tom Locke
To:Stephen Schumacher
Cc:Board of Health; Allison Berry, Clallam County Health Officer; news@ptleader.com; PT Free Press
Subject:Re: Accountability for Jeffco"s 45-Cycle Threshold PCR Test
Date:Monday, February 1, 2021 3:50:46 PM
Mr. Schumacher,
Cycle threshold values on PCR tests performed to detect SARS-CoV-2 are not routinely reported by laboratories tohealth departments or the person ordering the test. The Washington State Department of Health establishesstandards for what is considered a positive PCR test and is reportable as a notifiable condition. The local healthofficer has nothing to do with establishing CT parameters or any other diagnostic lab parameter. If you have anissue with CT values you should take it up with Washington DOH or the FDA. Jefferson County Public Health doescase investigations and contact tracing of all positive tests reported to Washington State and available to us througha confidential on-line registry known as WEDSS.
The fact that a thermal cycler can perform up to 45 amplification cycles does not mean that ALL tests are amplifiedto that degree. Samples are cycled until a signal is detected or they have undergone the maximum amplification ofthe testing protocol. Samples can have high CT values for many reasons -- poor sample quality, degradation of thesample during transport, low viral levels in the person being tested, and testing late in illness when fragments ofnon-replicating virus can be detected. And it is certainly true that high CT values correlate with lower transmissionrisk (assuming adequate sample collection and specimen transport). Setting standards for FDA approved diagnostictests is a federal regulatory function. States set standards for notifiable conditions such as SARS-CoV-2 infection. County health officers, local boards of health, county boards of commissioners, and public hospital districtcommissioners have nothing to do with these decisions.
Again, if you have grave concerns that the Washington State Department of Health is using scientificallyindefensible criteria for determining which COVID-19 PCR tests are positive, please share your expertise andconcerns with them. These criteria are not set by county health officers or local hospital districts. Nor do wemanufacture or license the PCR machines that are used to test diagnostic specimens for SARS-CoV-2. We rely onthese tools along with our case investigations (looking at exposure risk, symptom onset, and other risk factors) inassessing cases. False positive tests can occur with any diagnostic technology. They appear to be quite infrequentwith PCR testing, especially when a person has a COVID-like illness or a recent exposure to a confirmed case. Ifyour goal is to support the pandemic denialism that Ms. Huenke promotes in the "Port Townsend Free Press" articleyou reference, I could not disagree more. With the spread of more transmissible variants of SARS-CoV-2, thesocial cost of pandemic denialism is increasing. If sizeable numbers of people indulge in the wishful thinking thatattempts to control COVID-19 transmission are unnecessary, it is only a matter of time before variant strainsbecome predominant. We still have time to avert this future or at least slow it enough to allow widespread vaccinedeployment. I urge you to join the community fight against COVID-19 and stop attacking those who are workinglong hours trying to protect their community from the worst public health emergency in the last 100 years.
Sincerely,
Thomas Locke, MD, MPHJefferson County Health Officer________________________________________From: Stephen Schumacher <solmaker@olympus.net>Sent: Sunday, January 31, 2021 8:28 PMCc: Board of Health; Tom Locke; Allison Berry, Clallam County Health Officer; news@ptleader.com; PT FreePressSubject: Accountability for Jeffco's 45-Cycle Threshold PCR Test
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Dear Jefferson County Commissioners,
On September 2, 2020, I sent the following Public Comment to the
Jefferson County Board of Health and Health Officer Dr. Tom Locke:
"Per the August 29 New York Times report [of 90% false positives at40-cycle threshold], I'm concerned about the criteria used todetermine confirmed cases of COVID-19 in Jefferson County. Do allthese cases exhibit symptoms, or are "cases" being equated topositive test results? If the latter, what percentage of casesexhibit symptoms? Are positive test results being recorded using PCRtests, and if so, what is the Cycle Threshold value used for these tests?"
I never received any answers to these questions nor have seen themaddressed by Dr. Locke in the press.
Last week the Port Townsend Free Press reported that JeffersonHealthcare is "using a PCR assay with a 45-cycle threshold, wellbeyond the outer limits of reliability."https://www.porttownsendfreepress.com/2021/01/25/is-jefferson-county-health-department-overstating-covid-case-numbers/
This revelation raises various accountability issues, including:
1) Why did our county have to wait nearly 4 months to learn about its45-cycle threshold from a fortuitous Public Records Request?
2) Since Dr. Locke was also Clallam Health Officer until recently, isthis same unreliable 45 Ct test also in use throughout Clallam County?
3) Was the choice to use this 45 Ct test ever discussed and approvedby the Jefferson County Board of Health or County Commissioners? Ifnot, was it ever even reported and its significance explained to them?
4) Does Dr. Locke or anybody else keep statistical track ofcumulative cycle counts for positive tests and resulting cases in ourcounty, or is this info unavailable or being ignored? Could thisinformation be regularly published in the media, or at least be madeavailable upon request?
5) Does our county always order a second test following a positivePCR result, and if not, how often and on what basis? Are allpositive tests treated as COVID-19 cases regardless of symptoms, andif not, how often has high cycle count been used to discard extremelyweak positive test results?
6) How many county residents have been reported as cases,quarantined, and contact-traced based on cycle counts above 33, whenthe CDC shows "it is extremely difficult to detect any live virus ina sample above a threshold of 33 cycles"?
Yours truly,Stephen Schumacher2023 E. Sims Way #200Port Townsend, WA 98368