THE DELTA VARIANT AND BEYOND--EXPERT COVID-19 UPDATE

I just sat in on a Covid-19 update presented by the Newswise science news service featuring three experts:

Perry Halkitis, a public health psychologist and applied statistician at New Jersey's Rutgers University,

Eleanor Wilson, a medical doctor and infections disease specialist at the University of Maryland, and

David Souleles, Director of UC Irvine's Covid-19 response team, recently retired .Orange County Public Health Director

Delta is for Dangerous . . .

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The focus of the update was the emergence and trajectory of the delta variant and what that implies for the US.

Here are some of the key points the three experts made:

--The delta variant is a serious threat in the US and worldwide.

--As recently reported, the level of viremia--the viral load in the bloodstream--from a delta-covid infection is 1,000 times higher than from previous versions of the virus. That's probably what is making it so infectious.

--According to Dr. Wilson, the infectiousness, or "R-nought" value, of the original version of Covid-19 was estimated to be between 1 and 3. Statistically that means that one infected person would pass the virus to one to three others. The beta version's R value was between 4 and 6. The delta variant is 8 or 9. The only virus known to be more easily transmitted is measles, with an R value of 13.

--Unfortunately, the current vaccines appear to offer less protection against delta than against earlier versions of the virus. However, even though they may not completely protect against catching the virus, they are still highly effective at preventing serious illness, hospitalization and death. As such, vaccines remain our most important and urgent line of defense. "If we want to get back to normal life, we need our vaccination rates to be much higher," Souleles says. "That's priority number one to get our lives closer to what they were in January of 2020."

--That doesn't just include the US. The billions of people worldwide who are still not vaccinated are not just at risk personally, but represent a huge reservoir of current and future Covid-19 cases and so a huge opportunity for the virus to continue to mutate and spin off even more dangerous variants. "It's a global problem," says Wilson. "We have to vaccinate everyone. If we give the virus fewer opportunities to replicate, we win."

--All three of the experts were very concerned about the portion of the US population that are not yet vaccinated. They emphasize the importance of recognizing that this is not a monolithic group of dedicated vaccine refusers. Instead, these are individuals with many different issues, including very real medical, scheduling or other practical issues, normal anxieties and fears, such as a fear of needles, along with exposure to partial or incorrect information, and, unfortunately, a substantial number of people with politicized resistance to the vaccine and other protective measures. 

--They advocate both continued public education and persistent one-on-one outreach, aimed at recognizing and addressing each person's specific issues. "The media need to help people figure out what's real and what's not real, people who are being bombarded by misinformation," says Halkitis.  

"It takes a lot of conversation, but you have to keep doing it," says Wilson. To which Souleles adds, "Not just one conversation, maybe three, four or five."

--However, when education and patient one-to-one persuasion don't work, stronger steps may need to be taken. "I'd take a "tough-guy-from-New-York" approach," says Halkitis. "If you live in a civil society and you want to navigate spaces like concerts, restaurants, jobs and schools, you need to be vaccinated. Macron did it in France. If you want your children to go to school, they have to be vaccinated."

--All three agree that we need to track the course of the delta variant and any new variants that emerge with great attention, and that they could easily force a re-instatement of controls that have only recently been lifted. "Where we were six weeks ago is not where we are today," says Halkitis. "The next week will be very significant."

To summarize, the delta variant is highly contagious, surging rapidly, and is a potential game-changer. Everyone is eager to get back to something like the old normal, or on to a less restrictive new normal, but ultimately, it's the trajectory of the virus that will determine that. That trajectory is at least partly under our control through vaccination and other public health measures that we're all too familiar with. 

"We've got the tools," Souleles says. "We've just got to apply them on a broad scale."

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REA 7/23/21

NOW WE KNOW WHY DELTA IS SO DEVASTATING

The delta variant of the covid-19 virus is now the dominant strain in the U.S. and worldwide, accounting for more than half of new infections and driving up hospitalization rates and deaths in many U.S. states and multiple countries. 

We now have the first clues as to why the delta variant spreads so easily--at least twice as fast as the original virus. Just-released research from China reveals that the variant was detected in infected people two days earlier than was typical of the original virus--in 4 vs. 6 days--and, strikingly, the number of virus particles produced and potentially spread by sufferers was up to 1260 times higher.

Credit: Fortune.com

"This virus has surprised us," says  Emma Hodcroft, a molecular epidemiologist at the University of Bern, Switzerland, after reviewing the new study. 

The one-two punch of faster development after infection and vastly higher viral load combine to make the virus more quickly and easily transmitted, and make testing-contact tracing and quarantine-one of the main weapons in the battle against the pandemic--less effective.

"Putting it all together, Delta's really difficult to stop," says Benjamin Cowling, an epidemiologist at the the University of Hong Kong.

Unfortunately, with low vaccination rates in many states, along with the relaxation of most covid-related restrictions, we're going to hear a lot more about this virulent covid variant.

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REA 7/22/21

EVEN THE VACCINATED NEED TO GUARD AGAINST VARIANT DELTA

Many of us who have been vaccinated against Covid-19 have at least started to lead more normal lives. Since getting my Pfizer shots, I've traveled by plane, stayed at a B&B and in friends' homes, eaten inside restaurants, and hugged (vaccinated) friends. It's felt great.

But from what I'm now reading, even if we're fully vaccinated, we may not be fully protected against the highly contagious Delta variant.

Credit: ISO-FORM LLC

From the laboratory, as reported in the prestigious journal Nature, we learn that one dose of either the Pfizer or the AstraZenaca vaccines "was poorly or not at all efficient against the Beta and Delta variants." Serum from just one person in 10 partially vaccinated people was able to neutralize the Delta variant. 

A bit more encouragingly, blood serum from 95 percent of people who'd gotten both shots of either vaccine did generate a neutralizing response. However, that response was just one-third to one-fifth as potent against Delta compared to Alpha.

And, in the outside world comes a report from Israel indicating that the Pfizer jab is just 64 percent effective in keeping vaccinated people from catching the Delta variant. The good news is that it appears to be 94 percent effective in preventing severe illness. Still, the actual numbers are not encouraging. In the recent two-week period surveyed, Israel recorded 1,528 new Covid cases. Of those, 1,271 were in fully vaccinated people. Thirty-seven people had to be hospitalized, of which 23 were fully vaccinated. Seventeen patients fell seriously ill, or which 11 had gotten both Pfizer shots.

More recent data from Israel, covering the week of June 27 through July 3 showed that a shockingly high percentage of new Covid cases--85 percent--hit fully vaccinated people. That's essentially the same percentage who are vaccinated in the whole Israeli population. At first glance this could indicate that the mRNA vaccines provide no protection against the delta variant. It's also possible that the 15 percent of the Israeli population who are nor vaccinated have already had Covid or are otherwise immune. In that case these data could indicate that vaccination provides no more protection than a prior bout with Covid. But in either case they clearly show that "breakthrough" infections from the delta variant are far from rare.

And an even more recent report from Israel finds that even two Pfizer jabs are just 39 percent effective in protecting people against the delta variant. The same report is quick to point out that the shots are 88 percent effective in preventing hospitalization and 91 percent effective against severe illness.

The Israeli numbers are described as preliminary and definitely are outliers compared to what some other countries are reporting. However, they clearly show that the Delta variant can sneak past the antibody defenses of a significant number of vaccinated individuals, corroborating what was seen in the lab.

If more proof were needed, an outbreak of the delta variant among staff and patients at a hospital in Calgary, Alberta, Canada provides it. Ten medical professionals who were fully vaccinated nonetheless came down with Covid-delta after attending a party. "It's quite a red flag, honestly," one Canadian health expert said.

It's reassuring that the vaccines still appear to be highly effective in preventing serious illness. Still, I don't want to risk even a mild case of Covid. So, until the Delta variant becomes much less prevalent, or until further data is significantly more reassuring, I'm dialing back from my more freewheeling behavior of the last few months.

"Normal" may be in sight, but, due to the highly contagious delta variant, it's not here yet.

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REA

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