A thread on PCR testing and cycle thresholds. More details are available in the linked article:

1/11
rationalground.com/why-mass-pcr-t…
The problem is that current PCR tests provide evidence of the presence of viral RNA but no information about whether the individual is infectious.

In a French study on the duration of infectiousness, scientists cultured samples from PCR tests and found...

2/11
... that the culture positivity rate (a measure of the viability of the virus) decreased with the number of cycles that it took to detect that virus. No culture was obtained from samples that required more than 34 cycles.

3/11
A recent New York Times article presented evidence that specimens detected in 27 to 34 cycles rarely show any live virus, and specimens detected above 34 cycles never show any live virus.

4/11
The FDA’s Instructions for Use for the CDC 2019-Novel Coronavirus (2019-nCoV) Real-Time RT-PCR Diagnostic Panel currently recommends a threshold of 40 cycles for a specimen to be considered positive, well above the recommendations of the studies cited above.

5/11
The decision to equate a positive PCR test with a “case” in the COVID-19 pandemic is not aligned with recommendations from the test manufacturers or with definitions of cases for other viruses.

6/11
For SARS-CoV-1, the CDC and WHO recommended testing only patients “with a high index of suspicion for having SARS-CoV-1 disease” and re-testing positive specimens in a reference laboratory.

7/11
When a PCR specimen indicated infection, the recommendation was to test a second specimen.

The new recommendation to only test symptomatic or exposed people is a good start to address the hysteria caused by rising case numbers, particularly in young people.

8/11
However, an additional change is needed: the FDA recommendation for 40 cycles of amplification in PCR testing is far too sensitive and is leading to alarm about high numbers of “cases” in asymptomatic people

9/11
The FDA should update their guidance to recommend no more than 34 cycles, require labs to communicate the number of cycles required to detect the virus for each positive test, and...

10/11
... require labs to disclose the cycle threshold for all previous COVID tests to clean up the inflated statistics (cases, hospitalizations, and deaths) associated with test results that exceeded 34 cycles.

11/11

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More from @jhaskinscabrera

16 Sep
Florida reported 152 deaths today (Tues and Wed are catch-up days). Changes were reported on 58 different dates, going back to June 10. Peak is July 30 (209) and 7-day moving avg peak is July 25 (200) with a second peak on August 5 (198).

#RationalGround

1/6 Image
Here are the actual dates of death:

9/15 - 4
9/14 - 5
9/13 - 1
9/12 - 3
9/11 - 3
9/10 - 5
9/9 - 6
9/8 - 1
9/7 - 5
9/6 - 4
9/5 - 3
9/4 - 6
9/3 - 3
9/2 - 4
9/1 - 6
8/31 - 2
8/30 - 6
8/29 - 3
8/28 - 1
8/27 - 4
8/26 - 7
8/25 - 3
8/24 - 4
8/23 - 1
8/22 - 4
8/21 - 4
(more)

2/6
8/20 - 1
8/19 - 3
8/18 - 1
8/17 - 3
8/16 - 1
8/15 - 2
8/12 - 1
8/11 - 1
8/10 - 3
8/9 - 1
8/7 - 3
8/6 - 1
8/5 - 1
8/3 - 2
8/2 - 1
8/1 - 3
7/31 - 1
7/30 - 2
7/29 - 2
7/28 - 4
7/27 - 1
7/26 - 4
7/24 - 2
7/22 - 1
7/21 - 2
7/20 - 2
7/19 - 2
7/18 - 1
7/11 - 1
7/2 - 1
(more)

3/6
Read 6 tweets
12 Sep
The joys of living in a college town (Gainesville, FL - University of Florida). Our positive tests had settled from a summer plateau of 80 to around 40-50, then the students arrived (classes started 8/31):

1/6
7-day moving average was steadily decreasing until...

2/6
83% of today's positive tests are in the 15-24 age group:

3/6
Read 6 tweets
11 Sep
Florida reported 176 deaths today. Changes were reported on 54 different dates, going back to July 4. 37 were in July, and 91 were in August. Peak is July 23 (208) and 7-day moving avg peak is July 25 (198) with a second peak on August 5 (195).

#RationalGround

1/6
47 of the deaths were in Miami-Dade, following 49 yesterday. It appears that a good chunk of the reported deaths are from Miami-Dade's backlog.

Here are the actual dates of death:

9/10 - 5
9/9 - 8
9/8 - 8
9/7 - 3
9/6 - 5
9/5 - 4
9/4 - 3
9/3 - 5
9/2 - 2
9/1 - 5
(more)

2/6
8/31 - 1
8/30 - 2
8/29 - 3
8/28 - 1
8/27 - 2
8/26 - 4
8/25 - 1
8/23 - 3
8/22 - 1
8/21 - 6
8/20 - 4
8/19 - 1
8/18 - 2
8/17 - 1
8/16 - 1
8/15 - 4
8/14 - 2
8/12 - 3
8/11 - 6
8/10 - 3
8/9 - 9
8/8 - 5
8/7 - 7
8/6 - 3
8/5 - 7
8/4 - 6
8/3 - 2
8/1 - 1
7/31 - 5
7/30 - 1
(more)

3/6
Read 6 tweets
11 Sep
We started out with Sweden's plan; Sweden's plan was accepted as THE WAY to deal with pandemics before March.

We were told that we needed to "pause" to make sure we had enough hospital capacity.

1/5
6 months later, we have plenty of hospital capacity and an untold number of people dying from lack of medical care for non-COVID issues.

Nobody in the U.S. died from COVID because of a lack of hospital capacity, but plenty are dying because fear kept them from care.

2/5
The lockdowns, the school closures, the masks have secondary effects that we will be discovering for decades to come.

There is plenty of evidence that lockdowns delay deaths but don't save lives in the long run. In fact, they cost lives from other causes.

3/5
Read 5 tweets
8 Sep
Statement that the University of Florida gave to Alachua County (read at today's County Commission meeting): “Enforcement of behavioral expectations to abide by university regulations and policy, state and local law, and the instructions of officials can be carried out...

1/6
by any designee of the Vice President of Student Affairs or other appropriate university officials. Enforcement of behavior found to be a violation of the Student Conduct Code may result in sanctions such as...

2/6
loss of privileges associated with being a University of Florida student or student organization, including suspension and expulsion. Students, it is critical you understand that on- and off-campus parties and disregard for face masks, physical distancing, ...

3/6
Read 6 tweets
7 Sep
It appears the panic pushers are down to one last scare tactic: long-term effects (there is simply no longer any concern that COVID will grow exponentially and overwhelm hospitals or lead to piles of bodies).

1/5
If we're going to hold normal life hostage to long-term effects, there are many diseases with much greater prevalence and consequences.

Diabetes, for example. Life-long effects. Should we eliminate that before resuming normal life?

2/5
Not to mention car accidents. Lots of potential long-term effects from amputations, etc. Should we eliminate car accidents before resuming normal life?

How low should medical/accident risks be before we're allowed to decide for ourselves on our level of risk?

3/5
Read 5 tweets

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