東京新聞よ、大丈夫か？ 海外特派員が役立たずなら、語学に堪能なリサーチャーを揃えて海外記事を総浚えし、大人風記事を書いてみたら如何か。
２月７日付「東京のコロナ感染者急減、積極的疫学調査縮小したから？ 専門家は無関係」記事で、結論的には「積極的追跡調査を縮小したため、これまで追えていた軽症者や無症状者を見逃しているのでは」という疑問を否定してみせた。
保健所の業務逼迫を理由に、優先順位を付けた大幅縮小方針への大転換を、暗に支持するのが狙いか？
これについて昨年９月、米ニューヨークタイムズに「Your Coronavirus Test Is Positive. Maybe It Shouldn't Be.」（https://www.nytimes.com/2020/08/29/health/coronavirus-testing.html）という興味深い記事があった。
「（当時の）ＰＣＲ検査では９０％近い偽陽性判定の可能性」という内容だ。
特に興味深かった箇所を抜粋すると。
The PCR test amplifies genetic matter from the virus in cycles; the fewer cycles required, the greater the amount of virus, or viral load, in the sample. The greater the viral load, the more likely the patient is to be contagious.
This number of amplification cycles needed to find the virus, called the cycle threshold, is never included in the results sent to doctors and coronavirus patients, although it could tell them how infectious the patients are.
In three sets of testing data that include cycle thresholds, compiled by officials in Massachusetts, New York and Nevada, up to 90 percent of people testing positive carried barely any virus, a review by The Times found.
One solution would be to adjust the cycle threshold used now to decide that a patient is infected. Most tests set the limit at 40, a few at 37. This means that you are positive for the coronavirus if the test process required up to 40 cycles, or 37, to detect the virus.
Tests with thresholds so high may detect not just live virus but also genetic fragments, leftovers from infection that pose no particular risk -- akin to finding a hair in a room long after a person has left, Dr. Mina said.
Officials at the Wadsworth Center, New York's state lab, have access to C.T. values from tests they have processed, and analyzed their numbers at The Times's request. In July, the lab identified 872 positive tests, based on a threshold of 40 cycles.
With a cutoff of 35, about 43 percent of those tests would no longer qualify as positive. About 63 percent would no longer be judged positive if the cycles were limited to 30.
In Massachusetts, from 85 to 90 percent of people who tested positive in July with a cycle threshold of 40 would have been deemed negative if the threshold were 30 cycles, Dr. Mina said. "I would say that none of those people should be contact-traced, not one," he said.
★つまり、サイクル閾値（Cycle Thresholds, CT）４０で陽性と判定された人の８５～９０％が、閾値３０では陰性と見なされたのだ。
それと、
今年の１月２０日、ＷＨＯから告知が出たよね。
「ＰＣＲ検査でサイクル閾値を高く設定すると誤検知が増加する事を認め、閾値を変更＝下げる事を推奨する」と。
日本でも、こっそりと閾値を下げていたら偽陽性率が減少だから、コロナ感染者数なんて激減だな。
★東京新聞よ、サイクル閾値が如何なっているのか位、突っ込めよ。それこそが存在価値だろう！★
