Does the vaccine work against mutant viruses?

Recently NHK News on-line reported the following:

変異ウイルスにワクチンは効くの？

2021年5月12日 16時12分

国内で接種が進む新型コロナのワクチンは変異ウイルスにどこまで有効なのか。

横浜市立大学の研究グループがワクチンを2回接種した100人余りについて分析したところ、およそ9割の人は変異株に対して効果が期待できる抗体が体内に作られていたという研究結果をまとめました。

新型コロナウイルスは次々と変異を繰り返し、ワクチンが効きにくくなる可能性が指摘されている変異ウイルスも出てきています。

このため、横浜市立大学の研究グループは、国内で接種されているワクチン（ファイザー製）が変異ウイルスにどこまで有効なのかを調べる研究を実施しました。

ことし3月から4月にかけてワクチンを2回接種した医療従事者105人を対象に、血液を採取して、変異ウイルスへの感染を防ぐ働きのある「中和抗体」が、どこまで作られているかを調べました。

分析の結果、全体の89％の人はイギリスや南アフリカ、それにブラジルなどで合わせて合わせて7つの変異ウイルスすべてについて、効果が期待できる量の中和抗体が、体内に作られていたことがわかりました。

1回目2割未満の変異株も→2回接種で9割以上の効果に

変異ウイルス別に見るとイギリス株は94％、南アフリカ株は90％、ブラジル株は94％、インド株は97％、カリフォルニア株は97％、ニューヨーク株は98％、東京などで見つかったE484Kという変異のある由来不明株は97％の人に効果が期待できる量の中和抗体が確認されたということです。

従来株は99％の人で確認されました。

一方で、1回目の接種後では、イギリス株は18％、南アフリカ株は21％、ブラジル株は16％、インド株は37％、カリフォルニア株は39％、ニューヨーク株は55％、由来不明株は34％の人にとどまったということです。

従来株は57％でした。

研究グループのメンバーで横浜市立大学医学部の山中竹春教授は「ワクチンは2回接種すれば現在出てきている変異ウイルスに対しても中和抗体による免疫を期待できる結果となった。ただ、全員に中和抗体ができるわけではなく、個人差もある。今後さらに対象者を広げてデータを蓄積していきたい」と話しています。

Translation

How effective was the new corona vaccine inoculated in Japan against mutant viruses?

When a research group at Yokohama City University summarized the research results by analyzing about 100 people who received the vaccine twice, about 90% of the people had produced the body antibodies that could be expected to be effective against mutant strains.

As the new coronavirus was repeating mutation continuously, it had been pointed out that some mutant viruses could make the vaccine less effective.

For this reason, a research group at Yokohama City University conducted a study to find out how effective the inoculated vaccine (manufactured by Pfizer) was against mutant viruses in Japan.

From March to April this year, blood was collected from 105 healthcare workers who received the vaccine twice to check to what extent "neutralizing antibodies" had been made to prevent infection from mutant viruses.

As a result of the analysis, it was found that 89% of the total people had neutralizing antibodies in the body in a quantity that could be expected to be effective for mutant viruses from the United Kingdom, South Africa, Brazil, etc. up to seven kinds in total.

From less than 20% effective for mutant strains after the first inoculation → to more than 90% effective after the second inoculation

Effectiveness by mutant virus, 94% for British strains, 90% for South African strains, 94% for Brazilian strains, 97% for Indian strains, 97% for California strains, 98% for New York strains. For the strains of unknown origin called E484K found in Tokyo etc., it was confirmed to have an amount of neutralizing antibody that could expect to be effective in 97% of the people.

For traditional strains, 99% of people were confirmed.

On the other hand, after the first inoculation, effectiveness was 18% for British strains, 21% for South African strains, 16% for Brazilian strains, 37% for Indian strains, 39% for California strains, 55% for New York strains, and for the unknown strains it was only 34% of the people.

For the conventional strain it was 57%.

Professor Takeharu Yamanaka (山中竹春) of Yokohama City University School of Medicine (横浜市立大学医学部) who was a member of this research group said, "If you inoculate the vaccine twice, you can expect immunity with neutralizing antibodies against the mutant virus that is currently appearing. It is not possible to produce neutralizing antibodies in everyone, and there are individual differences. In the future we would like to further expand the target audience and accumulate data. "

So, the purpose of this study is to check for the extent of "neutralizing antibodies” produced by the vaccine manufactured by Pfizer in preventing infection from mutant viruses. The data collected so far show that Pfizer vaccine is effective. Although the scale of this study is very small, still it is good news in encouraging people to choose the Covid-19 made by Pfizer. It is obvious that not all vaccines are born equal.