屋外でのCOVID-19感染は全体の1%以下

屋外でのCOVID-19感染は全体の10％以下とのCDCの発表は間違い。実際は1%以下　https://t.co/vII5ZSN5Q1 屋外感染はデータに乏しく根拠となってるシンガポールの建設現場の例は暑いこの国にて冷房の効いた屋内ミーティング・食事時に起きたものと推定される。

— Spica (@Kelangdbn) May 12, 2021

　A study from Ireland, which seems to have been more precise about the definition of outdoors, put the share of such transmission at 0.1 percent. A study of 7,324 cases from China found a single instance of outdoor transmission, involving a conversation between two people.

“I’m sure it’s possible for transmission to occur outdoors in the right circumstances,” Dr. Aaron Richterman of the University of Pennsylvania told me, “but if we had to put a number on it, I would say much less than 1 percent.”

なるほどね。一人で外歩くときマスクしなくてもいいわけだね。

今日昼間電車乗って座っていたら隣の老婦人２人が隣り合わせでマスクしながらだがペチャクチャ喋っていた。窓は開いていたが、こわかったので立って他の車輌に移った。

Erring on the side of protection — by exaggerating the risks of outdoor transmission — may seem to have few downsides. But it has contributed to widespread public confusion about what really matters. Some Americans are ignoring the C.D.C.’s elaborate guidelines and ditching their masks, even indoors, while others continue to harass people who walk around outdoors without a mask.

All the while, the scientific evidence points to a conclusion that is much simpler than the C.D.C.’s message: Masks make a huge difference indoors and rarely matter outdoors.

屋内でマスクするとしないとでは大違い。屋外ではほとんど問題にならない、と。