Is the first coronavirus that caused the pandemic still present? – Orange County Register

Of course, I know alpha, beta, and delta (a virus, formerly known as B.1.617.2, like Prince).

But do you know Delta AY? And epsilon, gamma, iota, lambda, mu, theta? All of these variants of SARS-CoV-2 have been recorded in Southern California, and dozens more versions of the virus are prevalent worldwide, such as the little Dr. Evils in the Austin Powers movie.

So what happened to the “original” virus?The first one to jump from Bats and laboratories — or anywhere — To humans Those who were immunologically powerlessDid you end up killing nearly 5 million people and almost shutting down the world economy?

Dr. George Rutherford, a professor of epidemiology and biostatistics at the University of California, San Francisco, said “at least the path of human dinosaurs” is gone.

“It has been replaced,” said Andrew Neumer, an epidemiologist and demographer at the University of California, Irvine, who studies infectious diseases.

No one can say 100% sure that it’s gone, but Neumer said. And Rutherford adds this note:

“God knows what’s happening with bats.”

Welcome to this friendly tutorial on virus mutations and why your life depends on it.

SARS-CoV-2, which surfaced in Wuhan, China in 2019, was probably not the original, Researchers say. And the version that swept the United States in the fall of 2020 was already a mutation of the Wuhan version. And what was steamed across America this summer was still different.

Scientist recorded Virus version score It causes COVID-19 worldwide, and thanks to gene sequencing, it is possible to pinpoint exactly where they circulate. Sometimes those genetic changes are of little importance. At times, they make the virus much better and therefore more dangerous in avoiding human infections and treatments.

The US Centers for Disease Control and Prevention only offers highly contagious Delta B.1.617.2 and AY strains.Variant of concernHere in the United States, the World Health Organization also includes alpha, beta and gamma “Variant of Concern” List..

Notable up-and-coming mutants? WHO is on the lookout for Lambda and Mu.

Once the era of viruses

Scientists saw this coming.

Michael Buchmeier, a UCI infectious disease researcher who has been studying the coronavirus for decades, returns us to the original strain that caused the SARS-1 outbreak in 2002-03 for about 20 years.

At that time, only 12 other animal or human coronaviruses were known.

SARS-1 is a raccoon-like masked animal that combines two or more strains of the bat coronavirus when jumping to palm civet, which is widely sold in the living animal market in Asia. He said it was likely to have occurred in. There, the virus was amplified and adapted, eventually infecting humans. It has spread widely to China, Hong Kong, Taiwan and Canada for travel.

The case fatality rate was 10%. It was close to 50% for people over the age of 50.

However, there are important differences between SARS-1 and SARS-2. SARS-1 infection is always symptomatic in nature, making it much easier to detect and isolate the outbreak. SARS-2 can spread to asymptomatic individuals and is much more difficult to stop.

So where is the virus now?

“SARS-1 as a unique pathogen appears to be” extinct “in nature, but the conditions that caused it still exist,” Buchmeier said.

“That is, the presence of the coronavirus found in wild bats, especially horseshoe-shaped bats common in South Asia and China, and the breeding of suitable amplified hosts such as jade cats, raccoon dogs, and now pangolins. The virus can be adapted to infect humans. “

Hundreds of viruses have been isolated from bats in Asia and around the world, many of which are coronaviruses that can recombine to dangerous pathogens, he said.

Paper Clinical Microbiology Review, Published in 2007, it issued a warning. “Coronavirus is well known to undergo genetic recombination and can lead to new genotypes and developments. Along with the exotic mammal-eating culture in southern China, the horseshoe-shaped bat has a large SARS-CoV-like virus. The existence of a depot is a timed bomb. The need for preparation should not be ignored as SARS and other new viruses can reappear from animals and laboratories. “

In 2015, another Paper, journal nature, He warned of “the potential risk of SARS-CoV reappearing from viruses that are currently prevalent in bat populations.”

And here it is. The exact origin of the virus that caused the COVID-19 pandemic remains an official mystery and can always be one. In addition to the widely accepted bat / fresh market theory, there is suspicion that the virus may have leaked from the Wuhan Institute. WHO has appointed 25 new members Scientific advisory group on the origin of new pathogens, Working with scientists around the world, trying to understand that part.

next?

Genetic flexibility is a superpower of RNA viruses.

“This flexibility creates a herd of related virus” progeny “in each round of replication, allowing the virus to choose the optimal genetic makeup for a particular host in the form of the variant virus it is currently experiencing. .. Buch Meyer Said in a recent explainer..

“Mutations are always present in progeny viruses and may be selected if there is an advantage in replication in new host species.”

The alpha version, discovered in the UK last year, was much more infectious than the earlier version. And Alpha created beta, gamma, and delta variants. As can be seen from the summer surge, Delta is about twice as contagious as Alpha.

How did Delta do this? It was adapted to produce 1,000 times more virus in the nasal passages and upper respiratory tract early in the infection when people may be asymptomatic.

This has two distinct advantages from a viral point of view. Splashes from a person’s upper respiratory tract, for example, sneeze, spit out much more virus into the air to find new hosts. The human immune response is not as strong in the upper respiratory tract as in the lower respiratory tract, Buchmeier said.

The combination leads to many asymptomatic carriers and then spreads to others.

So far, the mutants do not appear to reduce the effectiveness of the vaccine, but they are squeezing the effectiveness of the treatment.

Variants of gamma, beta, kappa, mu, and zeta may be moderately less responsive to some antibody therapies, whereas iota is significantly less responsive to some antibody therapies. … apparently … California Public Health Service.

Epsilon, on the other hand, appears to significantly reduce the effectiveness of some antibody treatments and increase infection by 20%.

Mutation Nation

Each new infection is a new opportunity for the virus to mutate into something else. Maybe something that isn’t too much of a hassle. Maybe more annoying.

“What I’m worried about the upcoming winter wave is that there aren’t that many varieties. We need to get more people to get vaccinated,” said UCI Neumer. “75 percent is not enough to protect some age groups.”

Vaccination does not prevent infection, but even highly contagious delta mutants are very protective against serious illness, hospitalization, and death.

“The clear message is that unless vaccination of the population is incomplete and apparently effective social distance and masking are observed, it is very likely that more waves will be seen.” Buchmeier said.

Will SARS-CoV-2 mutate to something even more deadly?The crystal ball is cloudy, but many experts Don’t expect it to happen.. But they expect it to continue to circulate as part of the “human virome” — a complete collection of viruses inside and outside the human body — for a very long time.

Variants of the virus will continue to emerge and some may spread more.

However, as with the flu, the threat is imminent, even if it eventually reconciles with the virus. Buchmeier said the SARS-CoV-1 and SARS-CoV-2 precursors remain in bats and may be a repository for future human infection cycles.