Vaccinated people can slow the spread of COVID-19 and reducing the chances of “bad mutations”, said Temasek CEO Ho Ching as she called for the community to “vaccinate where we can and not wait”.
In one of her many Facebook posts on Monday (6 September), the wife of Prime Minister Lee Hsien Loong highlighted a Bloomberg article in which a public health expert said that undervaccinated pockets of people create more opportunities for the virus to mutate.
In the article, a professor of public health at West Virginia University, Christopher Martin, was answering a reader’s question about whether new, vaccine-resistant COVID variants could develop if many people remain unvaccinated.
The professor responded, “Large numbers of unvaccinated people do make variants more likely.”
He explained that COVID-19 mutations happen when the virus makes mistakes when copying itself, thus creating slightly different versions of itself.
“If any one of these random errors confers an advantage to that virus, such as making it more contagious like delta, that variant can quickly become the dominant one circulating in the population,” he said.
Paraphrasing his explanation of how virus variants come to be, Mdm Ho noted in her post that human beings are “bioreactors” which enable more variants to be produced over time.
She also highlighted that COVID variants appeared to be more infectious than the standard flu, meaning it would infect more people a lot quicker.
“While flu seems pervasive, the infectiousness of flu is typically around 1.2~1.4. This means on average, it takes 5 cases to infect 6 or 7 others,” wrote Mdm Ho.
“In contrast, even the earlier Covid variants have R0 of 2.4~2.8. This infectiousness was double that of flu.”
The Delta variant, which is most dominant right now, has an even higher rate of 5 to 8, she said.
Attempting to stress the significance of this, Mdm Ho noted that the higher infectiousness of COVID infecting more people at a higher rate means that “We have 10s and 100s of millions of infected people, each a huge bioreactor reproducing the virus and making copying mistakes that are known as mutations.”
She also explained that the COVID-19 virus is among the largest of viruses, and that it has a “self correction mechanism” to prevent some mistakes when copying itself.
Going further, she noted that the top structure of the coronarivus—the three-headed “flower” on top of the spike—can mutate while the lower part of the head which joins the rest of the cell is a “highly conserved area” where it is difficult to make copying mistakes
Mdm Ho noted: “The estimate was that the mutation rate would be 1-2 a month.”
“Nonetheless with the huge numbers of cases blazing out of control in many parts of the world, those one or two a month rate adds up, and we are seeing lots more.”
She added that in some immunocompromised patients, doctors are even seeing “fast and rapid multiple mutations” in a single person. However, she added that these patients have been isolated in hospitals so their mutations didn’t “escape into the open”.
Still, she cautioned that the same could be happening in other patients who are not isolated.
She concluded, “So pockets of the unvaccinated allow the virus to mutate more freely and faster. “
“Vaccinated folks can slow down the spread, and thus reduce the chances of bad mutations showing up,” she stressed, adding, “Let’s vaccinate where we can and not wait.”
