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Pfizer vaccine protects well against variants from South Africa and UK: NEJM. Additional information about variants and vaccines follows.

2021-05-06

A letter published in the New England Journal of Medicine (NEJM) dated May 5, 2021 reports that the Pfizer-BioNTech vaccine shows considerable effectiveness against two common variants: B.1.117 (first seen in the UK) and B.1.351 (first seen in South Africa.) From the letter:

The estimated effectiveness of the vaccine against any documented infection with the B.1.1.7 variant was 89.5% (95% confidence interval [CI], 85.9 to 92.3) at 14 or more days after the second dose (Table 1 and Table S2). The effectiveness against any documented infection with the B.1.351 variant was 75.0% (95% CI, 70.5 to 78.9). Vaccine effectiveness against severe, critical, or fatal disease due to infection with any SARS-CoV-2 (with the B.1.1.7 and B.1.351 variants being predominant within Qatar) was very high, at 97.4% (95% CI, 92.2 to 99.5). Sensitivity analyses confirmed these results (Table S3).

https://www.nejm.org/doi/full/10.1056/NEJMc2104974

In other words, the Pfizer-BioNTech vaccine is not as effective against the two variants as it was in the original trials conducted last year, but it still shows considerable strength against two variants. This is good, because the B.1.117 variant is now dominant in the US.

The B.1.351 variant is the one of greatest concern for evading the vaccines. The Astra Zeneca vaccine was not approved in South Africa because it appeared to be ineffective against this variant.

The Washington Post published a story yesterday about this NEJM letter. The story also reports that Moderna is testing a booster shot designed to directly protect against the B.1.351 variant. The second shot of both mRNA vaccines is essential for protection, and a booster would be the third shot– to be given three or more weeks after the second shot.

India has its own special variant contributing to an overwhelming wave of new infections.

In other variant news, India is suffering an overwhelming wave of infections, in part with a variant known as a “double mutant”– B.1.617. This variant has not been studied with regard to effectiveness of vaccines nor its relative severity. What little is known about this variant is summarized in this article in The Scientist from May 3, 2021. The article reports that India’s “Covaxin” vaccine is effective against the variant.

The India variant has just been found in a few cases in the US, so it will soon be present here along with all the other variants from around the world.

The India variant is known as a “double mutant” because it shows two changes that are common to variants now seen in California, with an amino acid replacement designated  L452R (described in this article in The Scientist) and the change designated E484Q, which is found in the South African variant B.1.351 as well as the Brazilian variant P.1. Naturally, “double mutant” is something of a misnomer because there are over twenty mutations causing amino acid changes in the spike protein that have been recorded since the original SARS-COV-2 discovery in December 2019.

Here’s an article in the British Journal of Medicine about the E484K mutation, which is similar to the E484Q mutation found in the Indian “double mutant.”

New coronavirus variants are a cause for concern, even if you’re vaccinated.

All these variants, with numerous changes to the spike protein, cause considerable concern because the original vaccines were tailored to the spike protein found in the original virus. We don’t know how effective vaccines will be against these variants until we test them– but it appears that the vaccines will not be as effective as they were at the beginning.

The vaccines will have to be changed within a year to keep up with the virus and its mutations. Fortunately, the mRNA vaccines are easily altered to fit new mutations. The technology of mRNA may lead to a revolution in vaccines for many other diseases, possibly including vaccines against multiple diseases in a single shot.

A third mRNA vaccine from Germany is in final trials as we speak: CureVac and its CVnCoV.

Even better, a vaccine called CVnCoV from CureVac that has not yet rolled out (in part because it didn’t receive the massive funding that the first two vaccines did) is also based on mRNA technology and will be refrigerator-storable at 41 degrees. A limitation of the first two vaccines is that they must be kept at very low temperatures, especially the Pfizer-BioNTech version which requires a freezer capable of maintaining below -76 degrees Fahrenheit (-60 degrees Celsius.)

The CureVac vaccine is described in this New York Times article that is tracking all the vaccines in development and is regularly updated with new information as it becomes available.

The CureVac story is an interesting one because the company turned down an offer from the former guy that would have given it a big pot of money if it agreed to make the vaccine for the US only. The offer was a typical unethical trick by the former guy, and we’re happy that they didn’t take him up on it.

Despite the delay caused by lack of big money, the company expects to finish its Phase III trials by the end of May. Many people hope that this vaccine will be the one that the whole world will use, partly because it is easy to store in an ordinary refrigerator.

Now that CureVac is close to proving the worth of its vaccine, it has signed up with multiple pharmaceutical companies, including Bayer, GSK (formerly Glaxo-Smith-Kline), Novartis, and Celonic. What’s more, the company is collaborating with Tesla’s Elon Musk on developing “microfactories” to produce its vaccine (see this article in the Observer from September of 2020.)

The CureVac vaccine will be easy to modify to address variants, just as the other mRNA vaccines are. Incidentally, here is another useful New York Times tracking article that assembles summary information about all the new variants as it comes in. These articles in the Times should be free to access, along with all its other content on the coronavirus.

Coronavirus spike protein damages vascular endothelial cells, meaning the virus is primarily a disease of blood vessels.

This article from the Annals of Diagnostic Pathology published online in December 2020 was listed in the PubMed Central archive at the National Library of Medicine in April of this year. It describes endothelial cell damage caused by the S1 spike protein alone in a mouse model. Apparently the coronavirus attacks the endothelial cells that line blood vessels first. All the damage that follows appears to start with blood vessels. This insight changes our perception of the novel coronavirus from a respiratory and pneumonia disease to a disease of blood vessels throughout the body– starting in the nose and throat, spreading to the lungs, and moving on from there.

photo by Liz Masoner via pixabay.com

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