Delta is bad. Is the next COVID variant worse?

We were very close to conquering COVID-19.

Now, as Delta dominates the world, experts worry: future versions of the virus could spread its infectious empire?

“The big concern is that the next mutation (potentially a few mutations) that may emerge can evade the vaccine,” said Dr. Rochelle Walensky of the US Centers for Disease Control and Prevention. I mentioned this week.

All viruses are constantly changing to newer versions. From generation to generation, they make random genetic errors.

I’m not going to cause any trouble.They said they had no dreams of greatness Dr. Joel Ernst, Professor of Medicine and Head of Experimental Medicine at the University of California, San Francisco.

“The only thing they want to do is duplicate,” he said. Citing a pioneering study by Stanford University microbiologist Stanley Falkou, Ernst said, “The goal of the virus is to become a virus.”

Early on, I wasn’t too worried about changes in the genetic makeup of the SARS-CoV-2 virus, which is stored in the single strand of RNA. Compared to influenza and HIV, the virus changes slowly as it spreads. Thanks to “proofreading” enzymes that correct potentially fatal copy errors, the genome normally accumulates only two single-letter mutations per month. The rate of change is about half that of influenza and one quarter that of HIV.

We saw it fail.One of the earliest named variants D614G, Carried a mutation that makes it easier for the virus to dock in human cells. But that mutation also made it more vulnerable to our antibodies.

“It was a ridiculous variant,” Ernst said. “There was that day, but we didn’t knock us out.”

But now we know that any change can have serious consequences.

Delta serves as an example of a textbook. The genetic code not only carries some of the successful mutations of previous variants, but also has the ability to spread twice as fast and release more offspring.

Data show that Delta is 40% to 60% more contagious than Alpha, almost twice as contagious as the original Wuhan strain of SARS-CoV-2. In addition, it grows at higher levels inside the throat and lungs than previous versions of the virus.

Only 49.3% of the US population is fully vaccinated, a characteristic that demonstrates the key to Delta’s continued evolution and spread. That’s why it quickly became the dominant stock in California, up from 53% in June to 84.4% of all new sequenced cases.

“It’s calm,” said the virologist. Shane Crotti Head of Vaccine Discovery Department at Lahora Immunology Institute. Variants “Alpha and Delta are 6 months apart from each other. Each has managed to become much more infectious.

“It definitely makes us uncertain about what the virus can do in the future,” he said.

Scientists are competing to understand which particular mutations are causing the transmission to skyrocket.

Particular attention has been paid to changes involving viral peplomer. This causes the virus to latch and invade human cells, causing infection.

Dr., an infectious disease expert Julie Personet, Professor of Medicine, Stanford University.

Alternatively, other parts of the virus may be better at the job.

“90% of the virus’s genome controls everything else, including replication rates,” Crotti said. “Therefore, it is plausible that a significant portion of this increased infectivity comes from a portion of this virus that we do not yet understand.”

Perhaps it contains an enzyme called RNA polymerase that is responsible for copying the genetic code when the virus replicates, Ernst suggested.

“We know that there are variants of RNA polymerase that make more viruses because they work better in influenza,” he said.

Changes to two other properties (pathogenicity and vaccine avoidance) can also change the pandemic.

So far, the virus has been particularly uncreative in evading vaccines and has a limited repertoire of changes. For example, the first delta variant found in India and the most common variant in California, despite being thousands of miles apart, tried to dodge antibodies using the same mutation. Mutants that emerged independently in South Africa and Brazil also share mutations.

“There are several ways the virus has mutated to avoid some of the antibody reactions,” Crotty said. “And it keeps coming up with them over and over again. And for now, it doesn’t seem to be a big deal.”

However, there are annoying signs of increased pathogenicity. Mortality associated with the Alpha, or UK variant, was about 64% higher than in previous variants. Currently, compared to Alpha, the Delta variant doubles the risk of unvaccinated hospitalization based on new Scottish data. Scientists don’t know if it’s due to a genetic change or just because of rapid growth.

Scientists added that it is unlikely to suddenly transform into a virus that kills suddenly. The pandemic has exploded as the virus is so sneaky and propagates in unvaccinated people who are healthy and social.

“Evolutionarily, killing your host isn’t very smart for the virus,” said Dr., a UCSF infection expert. Monica Gandhi..

Experts agreed that the United States must harness the power of genomics more fully to quickly detect the next mutation that could alter the pandemic’s orbit.