Skip to content
  • Wed. May 31st, 2023
wallallies
  • school from home
  • Nature Magazine
  • exchange student
  • the best campus
  • online school
  • Education
  • About Us
    • Advertise Here
    • Contact Us
    • Privacy Policy
    • Sitemap
News

Delta variant spreads COVID more quickly with powerful virus mutations

ByLavinia E. Smith

Aug 12, 2021 COVID, Delta, mutations, powerful, quickly, spreads, Variant, Virus
  • Delta is more dangerous because it has an incubation period of four days, rather than six, making people contagious sooner.
  • As of this week, the delta variant had caused at least 92% of the new infections in the U.S.
  • Scientists say it’s impossible to predict exactly how delta will behave in the future, although one expert said, “It’s going to get worse.”

Upon first inspection, the mutations in the highly contagious delta  coronavirus variant don’t look that worrisome.

For starters, delta has fewer genetic changes than earlier versions of the virus.

“When people saw that the epidemic in India was driven by delta, they did not suspect it would be so bad or overtake other variants,” said Trevor Bedford, an evolutionary biologist at the Fred Hutchinson Cancer Research Center.

But those expectations were wrong.

Delta has kept some of the most successful mutations found in earlier variants but also contains new genetic changes that enable it to spread twice as fast.

Delta is more dangerous in many ways. It has an incubation period of four days, rather than six, making people contagious sooner. When the pandemic began, people spread the original coronavirus to an average of two or three people. Today, people infected with delta infect six people, on average.

Delta variant Q&A:What to know about symptoms, vaccines and virulence

CDC mask recommendations have changed again.What’s required in your state?

As of this week, the delta variant had caused at least 92% of the new infections in the United States, according to covariants.org, a research firm in Bern, Switzerland.

Although delta isn’t necessarily any more lethal than other variants, it can kill huge numbers of people simply because it infects so many more, said Dr. Eric Topol, founder and director of the Scripps Research Translational Institute.

Scientists have sequenced delta’s mutations but are still trying to understand their significance, said Angela Rasmussen, a virologist at the University of Saskatchewan’s Vaccine and Infectious Disease Organization. “When we see the same mutations appearing repeatedly and independently, that suggests they’re important,” Rasmussen said.

Scientists have the best understanding of mutations on the so-called spike protein – which sticks out from the surface of the virus like a club – and which have been studied the most intensely because of its serious ramifications, Rasmussen said. The coronavirus uses the spike protein to enter human cells, and changes in the spike can help the virus evade antibodies.

Scientists believe one of the most important areas of the spike is the receptor-binding domain, the specific part of the protein that allows the virus to latch onto a receptor on the surface of our cells, said Vaughn Cooper, a professor of microbiology and molecular genetics at the University of Pittsburgh.

Receptors are like sockets or docking stations that allow proteins to interact with the cell. Once the virus gains entry to the cell, it can cause havoc, hijacking the cell’s genetic machinery and turning it into a virus-making factory.

Delta’s worrisome mix of mutations

Delta’s rapid spread is particularly surprising given it lacks two mutations that made earlier variants so scary.

Delta doesn’t have the N501Y spike mutation found in the alpha, beta and gamma variants, which enabled them to invade cells more successfully than the original virus. That mutation changed one amino acid – a building block of proteins – in the receptor-binding domain.

Delta also lacks the E484K mutation, which has made the gamma variant so worrisome. This genetic change, sometimes called “Eek,” allows the virus to spread even among vaccinated people. (Scientists use the Greek alphabet to name variants of concern.)

“The ‘D’ in delta stands for ‘different’ and a ‘detour’ to a different genomic mutation path,” Topol said. “But it doesn’t mean ‘doom,’” he said, noting that existing COVID-19 vaccines remain mostly effective against the delta variant.

Vaccines protect people from COVID-19 by providing them with antibodies that attach themselves to the spike protein, preventing the virus from entering cells. By dramatically reducing the number of viruses that enter cells, vaccines can prevent people from developing severe disease and make them less infectious to others.

Delta does share mutations with other successful variants. Like all the identified variants in circulation, delta contains a spike mutation called D614G, sometimes known as “Doug,” which became ubiquitous last year.

Scientists believe Doug increases the density of spike protein on the surface of viral particles and makes it easier for the virus to enter cells.

‘New science is worrisome’:What new masking guidelines means if you’re vaccinated 

Delta also has a spike mutation called P681R, which closely resembles a mutation in the alpha variant that appears to produce higher viral loads in patients, Cooper said. People infected with the delta variant have 1,000 times more virus in their respiratory tract, which makes them more likely to spread the virus when they sneeze, cough or talk.

The P681R mutation, also found in the kappa variant, is found at the beginning of a part of the genome called the furin cleavage site, Cooper said.

Furin is a naturally occurring human enzyme that gets hijacked by the coronavirus, which uses it to slice the spike protein into the optimal shape for entering the cell, Rasmussen said. The new mutation makes that sculpting more efficient, Rasmussen said.

Another delta mutation – also found in kappa and epsilon – is called L452R. Experiments suggest this mutation, which also affects the receptor-binding domain, acts to prevent antibodies from neutralizing the virus, Cooper said.

These mutations appear to be more formidable as a team than alone.

The genetic changes “are certainly doing something, but why that combination makes the delta variant more fit is not entirely obvious,” Bedford said. “Putting them together seems to matter.”

Delta also has developed genetic changes not seen in other variants.

One such spike mutation is called D950N. “This might be unique,” Cooper said. “We don’t see that anywhere else.”

The D950N mutation is different from other mutations because it’s located outside the receptor-binding domain in an area of the coronavirus genome that helps the virus fuse with human cells, Cooper said. Fusing with human cells allows the coronavirus to dump its genetic material into those cells.

This mutation could affect w
hich types of cells the virus infects, potentially allowing it to harm different organs and tissues. Mutations in this region also are associated with higher viral loads, Cooper said.

Delta also contains mutations in a part of the spike protein called the N-terminal domain, which provides a “supersite” for antibodies to latch onto the virus and prevent it from entering cells, said Dr. Hana Akselrod, an infectious diseases specialist at the George Washington University School of Medicine & Health Sciences.

Mutations in this region make monoclonal antibodies less effective in treating COVID-19 and increases the delta variant’s ability to escape vaccine-generated antibodies, Akselrod said. That may explain why vaccinated people are slightly more likely to become infected with delta, causing mostly mild illness but allowing them to transmit the virus.

New mask guidelines:CDC recommends masks for vaccinated people in high transmission areas

Delta’s future course 

Scientists say it’s impossible to predict exactly how delta will behave in the future, although Topol said “it’s going to get worse.”

Topol noted that delta outbreaks tend to last 10 to 12 weeks as the virus “burns through” susceptible populations.

If the United States continues to follow a pattern seen in the United Kingdom and the Netherlands, infections could rise from the current seven-day moving average of 42,000 cases to 250,000 a day. Yet Topol said the United States is unlikely to suffer the high death rates seen in India, Tunisia and Indonesia because nearly half the population here is fully vaccinated.

While some studies have concluded that the Johnson & Johnson vaccine stimulates strong and persistent antibodies against delta, a new report found that antibodies elicited by one shot may not be enough to neutralize the variant. Authors of that study, from the New York University Grossman School of Medicine, suggested a second dose may be needed.

Two doses of the Pfizer-BioNTech vaccine protect 94% of people from any symptomatic infection by the alpha variant, compared with 88% against the delta variant, according to a new study in the New England Journal of Medicine. Two doses of the AstraZeneca vaccine protect 75% of people from alpha and 67% from delta.

Cooper said COVID-19 vaccines offer remarkably good protection. “I will always celebrate these vaccines as the scientific achievements of my lifetime,” he said.

The best way to slow the evolution of variants is to share vaccines with the world, vaccinating as many people as possible, Bedford said. Because viruses undergo genetic changes only when they spread from one host to another, stopping transmission denies them a chance to mutate.

Whether the coronavirus evolves more deadly variants “is totally in our hands,” Cooper said. “If the number of infections remains high, it’s going to continue to evolve.”

By failing to contain the virus through vaccination, wearing masks and avoiding crowds, people are allowing the coronavirus to morph into increasingly dangerous forms, said Dr. William Haseltine, a former Harvard Medical School professor who helped design treatments for HIV/AIDS.

“It’s getting better, and we’re making it better,” he said. “Having half the population vaccinated and half unvaccinated and unprotected – that is the exact experiment I would design if I were a devil and trying to design a vaccine-busting virus.”

Post navigation

CDC data supports why vaccinated should wear masks
Trump-backed prospect Mike Carey wins main for Household seat in Ohio

By Lavinia E. Smith

Related Post

News

How to find home tutors near me

Oct 31, 2022 Lavinia E. Smith
News

13 Virtual School Activities that Students & Educators Love

Oct 30, 2022 Lavinia E. Smith
News

Now Hiring! – STORIES FROM SCHOOL AZ

Oct 29, 2022 Lavinia E. Smith
May 2023
M T W T F S S
1234567
891011121314
15161718192021
22232425262728
293031  
« Apr    
Archives
  • May 2023
  • April 2023
  • March 2023
  • February 2023
  • January 2023
  • December 2022
  • November 2022
  • October 2022
  • September 2022
  • August 2022
  • July 2022
  • June 2022
  • May 2022
  • April 2022
  • March 2022
  • January 2022
  • December 2021
  • November 2021
  • October 2021
  • September 2021
  • August 2021
  • July 2021
  • June 2021
  • May 2021
  • April 2021
  • March 2021
  • February 2021
  • January 2021
  • December 2020
  • November 2020
  • October 2020
  • November 2018
  • October 2018
  • December 2016
Recent Posts
  • Using the Internet to Get a Casino Gaming Job
  • History of Home Schooling
  • The Renaissance, Platonic Love and the Nous of Anaxagoras
  • Top Five Reasons Why You Should Choose To Go To College
  • Distance Learning Online Degree – Just Shattered – The Myth of a Degree From Distance Learning
BL
Tags
"Hssu College Of Education Program 6 Tratits Of Character Education Acbsp General Education Requirement Bilingual Education Is A Failure" Blue Education Background Board Of Education 89th Street Board Of Education ???? Bonner Springs Kansas Special Education Brad Baker Edience Education Career Objective For Higher Education Coates Education In The Street Confessional Education Focuault Country Education Rankings 2017 Cre Education Credits Crime Levels Based On Education Dallas Education Nibs Does Brazil Have Compulsory Education Education Expense Credit Ga Education For Psychiatrists Education Images To Color Eec1200 Syllebus Early Childhood Education Electrician Education Fullerton Enteral Feeding Client Education Example Intro To Education Rubric Fairfax Education Association Linked In Fixes To Higher Education Funding For Science Education High Income Students Education High Level Special Education History Of Education In Iraq How Improved Education Affects Society Hunters Education Instructors Association Hunting Education Nj Jeff Saks Berkeley Education Kurt Vonnegut Education Quotes Mexican Experience With Bilingual Education Michael Education System Mission Education Center Excell Olympics Education Activities Papers On Economics Of Education Poverty And Education Paper Topics Public Education Uganda Guardian Sandy Harvey Special Education Illinois Secretary Of Education Charter Schools Stem Computer Science Education Careers

scorpion pest control in las vegas 

Related Article

online school

Using the Internet to Get a Casino Gaming Job

May 30, 2023 Lavinia E. Smith
school from home

History of Home Schooling

May 30, 2023 Lavinia E. Smith
Nature Magazine

The Renaissance, Platonic Love and the Nous of Anaxagoras

May 29, 2023 Lavinia E. Smith
the best campus

Top Five Reasons Why You Should Choose To Go To College

May 28, 2023 Lavinia E. Smith
wallallies

Proudly powered by WordPress | Theme: Newsup by Themeansar.

  • Home
  • About Us
  • Advertise Here
  • Contact Us
  • Privacy Policy
  • Sitemap

WhatsApp us