Delta variant spreads in California as battle against COVID-19 enters uncertain phase

The Delta variant of the coronavirus is beginning to spread in California, offering a glimpse of how the battle once morest the pandemic will change as authorities move to protect a shrinking minority still at risk for not having been vaccinated.

The Delta variant can be twice as transmissible as the conventional strain. But California and the rest of the country are much more protected than ever once morest COVID-19. California has one of the highest vaccination rates in the country, and the United States has one of the highest per capita inoculation rates in the world.

And the vaccines available in the US are believed to be effective once morest the Delta variant, as they have been for all known variants. But that still leaves tens of millions of unvaccinated people potentially vulnerable.

“If you’re vaccinated, nothing will happen,” Dr. George Rutherford, an epidemiologist at UC San Francisco, said of the Delta variant. “If you are not vaccinated, you are lost.”

Authorities do not expect another deadly wave of COVID-19 similar to those that have hit the country three times in the last 15 months. The risk is rather that the Delta variant takes hold in pockets of unimmunized communities that have not previously been infected with the coronavirus.

This is the future that experts hope for: one in which the majority of the population, who are vaccinated, are well protected once morest the world’s worst pandemic in the last century, while risks remain for those who are not vaccinated.

Now, “almost all deaths from COVID-19 are especially tragic,” said Dr. Rochelle Walensky, director of the US Centers for Disease Control and Prevention, “because almost all deaths – especially among adults – due to COVID-19 are, at this time, entirely preventable.”

California is especially well placed to tackle the Delta variant, as 73% of the state’s adults have received at least one dose of the vaccine – even better than the respectable national rate of 66% – and because many other Californians have survived COVID-19 from previous waves.

“We will not see the surges that overwhelmed our hospital system,” said Dr. Robert Kim-Farley, a medical epidemiologist and infectious disease expert at the UCLA Fielding School of Public Health. “There just aren’t enough susceptible people right now to create those magnitudes of increase.”

Across the country, the average number of new coronavirus cases reported daily has fallen to regarding 11,000, one of the lowest numbers since the start of the pandemic and a 96% drop from the peak of more than 252,000 daily cases recorded last year. early January. At its height, regarding 3,500 Americans were dying a day from COVID-19, and now fewer than 300 Americans are dying a day.

Dr. Anthony Fauci, the US government’s top infectious disease expert, said he didn’t think the national daily death count was anywhere near previous peaks.

“I don’t think… you’re going to see things like 1,000 deaths a day. I think that is too much. But there is a danger — a real danger — that if vaccine hesitancy persists, there will be localized spikes,” Fauci said. “All of that is totally and completely avoidable by getting vaccinated.”

Experts don’t expect a return to the stay-at-home orders that shut down wide swaths of the economy due to the Delta variant, also known as B.1.617.2, which was first identified in India.

“No. Absolutely not. No, no, no, no,” said Dr. Eric Topol, director of the Scripps Research Translational Institute in La Jolla. “We are not going back. Really good, very potent and safe vaccines have put us in a strong position.”

That optimism is especially welcome in California, which last week finally reopened its economy following more than a year of coronavirus-related shutdowns and shutdowns.

During the height of last winter’s surge, nearly 550 Californians died daily from COVID-19. Now, California records regarding 20 deaths a day from COVID-19.

But just as important as the number of new cases being reported is the type of variants that are spreading through these additional infections. The Delta variant is appearing with worrying frequency, raising alarm bells at both the state and federal levels.

“The Delta variant is currently the biggest threat in the United States to our attempt to eliminate COVID-19,” Fauci said.

Nationwide, between May 9 and May 22, the Delta variant accounted for less than 3% of genomically sequenced coronavirus samples. But between June 6 and June 19, that share rose to more than 20%.

The UK, where authorities were recently forced to postpone a planned easing of COVID-19 restrictions due to a surge in coronavirus cases, offers a cautionary tale regarding the extraordinary infectivity of the Delta variant.

At the end of March there were only a small handful of cases of the Delta variant in the UK, but by early May the number of cases had risen to 25%. As of mid-June, 95% of cases were related to the Delta variant.

However, the recent increase in cases and hospitalizations in the UK remains very small compared to the winter increase. Daily coronavirus cases in the UK are down by more than 80% from the winter peak, while the number of people hospitalized with COVID-19 remains 97% lower.

Although the Delta variant is known to be considerably more infectious, experts differ on whether they believe it causes more severe disease than other coronavirus strains.

Fauci said this week that the variant is associated with greater disease severity, as reflected in the risk of hospitalization.

Topol agreed: “More and more young people are getting infected and ending up in hospital. That’s not a good sign.” In contrast, with conventional strains, the young — which Topol says refers to those under 40 — rarely ended up in the hospital.

But, Topol added, there is no evidence that the Delta variant is more likely to cause death than other variants.

The UK continues to report fewer than 15 daily COVID-19 deaths since early May, down from 1,300 deaths per day at the height of the pandemic.

Not everyone is convinced that the Delta variant is more likely to cause more severe disease.

COVID-19 hospitalizations in the UK are growing more slowly than new cases, meaning the chance of an infected person being hospitalized has been reduced, said Dr. Monica Gandhi, an infectious disease expert at UC San Francisco.

Another promising sign, according to Gandhi, is that there does not seem to be an increased risk for young children. Young children are already less likely to catch the coronavirus because they have far fewer proteins called ACE2 receptors in their noses that the coronavirus needs to access to infect the body.

In California, the Delta variant has gone from accounting for 1.8% of coronavirus samples tested in April to 4.8% of them in May.

The Delta variant is now the fourth most identified variant in California. The Alpha variant, identified for the first time in the United Kingdom (also known as B.1.1.7), follows in the lead, representing 58.6% of the samples.

Some counties report this data individually. Northern California’s most populous county, Santa Clara, for example, has confirmed 58 cases of the Delta variant.

And in Los Angeles County, authorities say they have identified 64 cases of the variant among residents from late April to early June, most of them confirmed in recent weeks.

Delta “is the most infectious variant that has been identified to date here in California,” Los Angeles County Public Health Director Barbara Ferrer said Tuesday. “And that means that for those people who are not vaccinated, it’s going to be a huge risk.”

Ferrer noted that much of the documented transmission in the county appears to be occurring in households, with 34 of the confirmed cases of the variant living with one or more people linked to other cases.

When the county updates its sequencing results once more, Ferrer said she is “confident that we will see a significant increase in specimens testing positive for the Delta variant because … it actually proliferates very rapidly.”

Vaccines that have been shown to be effective once morest the Delta variant include Pfizer-BioNTech’s two-dose vaccine and AstraZeneca’s two-dose inoculation – which is not yet licensed for use in the US but is in widespread use in the UK. and is similar to the one manufactured by Johnson & Johnson.

“We have the tools. So let’s use them and crush the outbreak,” Fauci said.

Among the vaccines available in the United States, both Pfizer-BioNTech’s and Moderna’s require two injections, given several weeks apart. Johnson & Johnson’s involves a single dose.

A recent study found that receiving both doses of the Pfizer-BioNTech vaccine was 88% effective once morest symptomatic disease caused by the Delta variant and 96% protective once morest hospitalization.

Although 73% of adult Californians have received at least one dose, only regarding 59% are fully vaccinated at this time, according to data from the Centers for Disease Control and Prevention.

Walensky warned that the Delta variant “represents a set of mutations that might lead to future mutations that evade our vaccine,” adding that “this is why it is more important than ever to get vaccinated now to stop the chain of infection, the chain of mutations.” .

Some experts are optimistic that this coronavirus will not mutate to the point of outperforming our vaccines.

“After these 18 months of evolution, we haven’t seen anything that has evaded the protection of our vaccines,” said Topol, who recently wrote on the subject for the journal Nature Medicine. But, he added, “we have to rush through the vaccination process, because that’s our best defense to prevent that from happening.”

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