地球，人間煉獄 CLIII (153 rd、153期) ：
| New #OxfordVaccine studyLatest research on the Oxford-AstraZeneca vaccine indicates that a long interval between first and second doses does not compromise the immune response after a late second dose.
Additionally, a third dose of the vaccine continues to boost antibodies against COVID-19.
Professor Sir Andrew Pollard, Professor of Paediatric Infection and Immunity and Lead Investigator of the Oxford University trial of the vaccine, says, ‘This should come as reassuring news to countries with lower supplies of the vaccine, who may be concerned about delays in providing second doses to their populations. There is an excellent response to a second dose, even after a 10 month delay from the first.’
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沈政男醫師說的統計學，其實十來分鐘就可懂。
https://en.wikipedia.org/wiki/Box_plot
箱形圖（英文：Box plot），又稱為盒鬚圖、盒式圖、盒狀圖或箱線圖，是一種用作顯示一組數據分散情況資料的統計圖。因型狀如箱子而得名。此圖中之盒子之外，也常會有線條在上下四分位數之外延伸出去，像是鬍鬚，因此也稱為盒鬚圖。
Box plot
【AZ遇delta變科興 混打保護力比兩劑BNT更強大】
附圖是最新《Lancet》（刺胳針）醫學期刊，關於新冠疫苗保護力的文章。
左邊是比較兩劑AZ與兩劑BNT對各種病毒株的中和力，也就是抗體把病毒吃掉的能力，你可以看到兩種疫苗的中和力對變異株明顯下降，到了delta變種其下降最多。
這樣一來，是不是中和力越好的疫苗，越是面對變異株就越顯重要？明顯可以看出BNT兩劑就是比AZ兩劑的中和力好，不管面對舊株或變異株都是如此。
中和力是實驗室數據，但因為最近蘇格蘭那篇做出了實際世界的類似數據，也就是兩劑BNT比兩劑AZ，在delta變種保護力上是60% vs. 73%，可見中和力數據對於delta變種依然適用。
所以說AZ疫苗遇到了delta變種，中和力就下降到科興疫苗等級了，但BNT仍能大略挺住。
當然，你會說，預防重症的效果還是很好！問題是以台灣的疫苗施打率，輕症會造成傳播，進而衍生大量重症，因此疫苗保護力仍是相當重要。
右圖是另一篇《Lancet》最新文章，乃將只打一劑AZ與AZ+BNT，也就是混打，來做比較。也是以中和抗體來比較，不是真實世界數據。
結果如何？AZ+BNT的中和抗體當然比一劑AZ好很多。為什麼不跟兩劑AZ比？因為AZ在某些國家已經不用了。
作者在討論時，從文獻列舉了兩劑AZ與兩劑BNT的中和抗體，結果如何？你可以從這些數據看出，當然，AZ+BNT比兩劑AZ產生更高中和抗體效價，但，重點來了，也比兩劑BNT產生更高中和抗體效價！
所以說混打有可能比打兩劑BNT，注意，是兩劑BNT，保護力更強大。
順便講一下疫苗施打的問題。好多家屬因為施打後猝死的新聞，不敢讓老人家打疫苗，這是多慮了，因為，想也知道，如果疫苗那麼毒，歐美會拿來用嗎？
防疫不只靠正直，更要靠直覺與常識。
如果你看得懂統計與流行病學，當然可以去查數據，但如果看不懂，就靠你的直覺與常識來判斷了。
也有人問到了Novavax疫苗，這支確實值得期待！有人說它比mRNA疫苗的保護力更好，這是錯誤的，頂多是差不多，因為中和抗體效價顯示如此。但它的副作用，也就是發燒痠痛之類比較少。問題是什麼時候上市與引進台灣，都不知道。
如果你想打Novavax卻等不到，那麼也可以考慮國產疫苗，因為技術是一樣。當然，必須有當白老鼠的心理準備，但白老鼠的下場很多都是好的。從中和抗體數據來看，國產疫苗的保護力很可能也是不錯，但就只是從實驗室數據來推估。
我反過來問：如果國產疫苗可以用中和抗體效價來推估保護力，為什麼混打不行？如果可以從Novavax來推估國產疫苗，為什麼不能從BNT來推估莫德納的混打保護力？
（圖片取材於Lancet網站）
![可能是顯示的文字是「 A Two Doses Oxford-AstraZeneca (AZD1 1222) vs. Pizer- fizer-BioNTech Wildtype D614G B.1.1.7 [>2560] t6n 1024 351 Control group 只打AZ一劑 256 A B.1.617.2 BNT在delta 仍比AZ中和力好 Intervention group 混打AZ+BNT 1905 64 BNT在舊株 和 [<40] 比AZ中和力好 [이] AZD1222 162b2 AZD1222 BNT162b2 AZD1222 AZD1 BNT1 62b2 AZD1222 BNT 162b2 AZD1 ZD1222 62b2 old-decrease (95%Conf. 2.1 Interval) 2.4 2.2) 2.4 antibody Log10 2.6) 2.5 2.5 2.8) 2.7) 對任何變異株 BNT比AZ中和力好2.5倍 7 14 Time since vaccination (days) 施打天數」的圖像](https://scontent.ftpe13-2.fna.fbcdn.net/v/t1.6435-9/201225626_4365667276881008_9094310404477629758_n.jpg?_nc_cat=104&ccb=1-3&_nc_sid=730e14&_nc_ohc=OHJ0Y_sG3TUAX-n6QDf&_nc_ht=scontent.ftpe13-2.fna&oh=740caf820396238997c5d0811bf581ed&oe=60DF87E7)
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Taiwan reported 60 new COVID-19 cases on Monday, the smallest rise in the daily figure since May 15. 6.28
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马来西亚官方表示，原定周一结束的封城由于境内新增染疫人数居高不下，现已决定延期，直到单日确诊人数降至4 000以下。马来西亚总理希望能在7月中旬达到解封条件。
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More parts of Australia have been locked down as authorities try to locate workers from a remote gold mine linked to five Covid-19 cases thought to be of the highly infectious Delta strain.
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「第5のがん治療法」と期待される光免疫療法。世界で研究論文が相次ぐ中、開発者の米国立衛生研究所（NIH）の小林久隆氏は「将来的に8～9割のがんに使える」と強調します。（会員向け記事です。登録無料）
Correlates of protection
ウェブ検索結果
F Krammer 著2021被引用数: 12 — Since the beginning of the COVID-19 pandemic, many scientists and public health officials assumed that infection with SARS-CoV-2 would protect from reinfection and that neutralising antibodies would correlate with ...
Correlates of immunity/correlates of protection - Wikipedia
https://en.wikipedia.org › wiki › corr...
Correlates of immunity/correlates of protection ... Correlates of immunity/protection to a virus or other infectious pathogen are measurable signs that a person (or other potential host) is immune, in the sense of being protected against becoming ...
World Health Organization 著2013被引用数: 34 — These data have been cited widely to support a PRN of 120 as a correlate of protection against clinical measles. Jack et al. (25) followed children vaccinated with the plasma-derived hepatitis B vaccine in the Gambia, and correlated their levels ...
Correlates of protection could be used to extrapolate efficacy from trials of new vaccines, and could speed development
保護的相關性可用於從新疫苗的試驗中推斷功效，並可以加速開發
NEW: Oxford researchers identify levels of antibody protection required to prevent symptomatic COVID-19.
The Oxford study finds:
• There remains a global shortage of vaccines to prevent COVID-19 and licensing new vaccines could help fill the gap.
• Researchers identify average antibody levels (called ‘correlates of protection’) required to prevent COVID-19 in populations
• Correlates of protection could be used to extrapolate efficacy from trials of new vaccines, and could speed development
Professor Sir Andrew Pollard, Director of the Oxford Vaccine Group, and Chief Investigator on the Oxford Vaccine Trial, said: ‘There is an urgent need to increase supply of vaccines for the world, but development and approval of new vaccines takes many months. We hope that the use of correlates by developers and regulators could speed up the process.’
Read more
https://www.ox.ac.uk/....../2021-06-25-oxford......
OX.AC.UK
Oxford researchers identify levels of antibody protection required to prevent symptomatic COVID-19 | University of
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