Today, with much fanfare The Washington Post announced the “largest genetic study of the coronavirus to date” and indicated the “coronavirus is mutating and potentially evolving amid rapid U.S. spread.” In addition, this study indicated “one strain becoming predominant in Houston over time.”
This ominous headline referred to an un-reviewed study from the BioRx website from Houston Methodist hospital, a part of the Texas Medical Center in central Houston. Reportedly, scientists have been sequencing the genome of the coronavirus since early March, when the virus first arrived in metropolitan Houston. The paper documents 5,085 sequences.
Those of you that follow my blog know my “love “of news outlets quoting unreviewed papers on BioRx. But this story gets worse!
Remarkably, the results were simply a reiteration of the now, well-know genetic alteration that replaces a single amino acid (an aspartic acid for a glycine at position 614) in the spike protein. This substitution has been documented in multiple publications over the past several months, and its significance is still unknown.
While larger studies have been performed on COVID mutations, this study was singled out because the authors indicated that mutations had increased from 71% of the COVID-19 isolates in April to approximately 99% of the coronaviruses isolated in July. They suggested it had improved infectivity over other SARS-CoV-2 viruses.
More disconcertingly, the article suggested that this and the other 5,000+ substitutions they identified (none of which had any functional significance attached to them) could lead to less efficacy for COVID-19 vaccines currently under development.
While most vaccines are directed against the spike protein, it has over 1400 amino acids and a single amino acid substitution will not invalidate a vaccine. There are also many reasons other than increased infectivity that can lead to dominance of a single viral strain. More importantly, if the D614G substitution leads to greater infectivity, it may be a positive since the death rate from coronavirus in Houston has decreased substantially during the time it has become the predominant virus there.
Even some of the experts whose comments were included in the Washington Post article were skeptical of the paper and its implications.
Kristian Andersen, an immunologist at the Scripps Research Institute in California, who was not involved in the study, downplayed the significance of the new study. He said it “just confirms what has already been described — G isolates increased in frequency over time.” As for the numerous other mutations the study finds, “they just catalogue them, but we don’t know if any of them have any functional relevance.”
The paper’s senior author, Dr. James Musser, said his interpretation is that D614G has been increasingly dominant in Houston and other areas because it is better adapted to spreading among humans. He acknowledged that his “scientific case is not closed on this matter.”
From all of this, I can only think that this aggressive announcement and text message on this, sent by the Washington Post, is simply an attempt to scare people and undermine confidence in COVID-19 vaccines.