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Sunday, August 7, 2022

COVID-19: Essential Vaccine to Curb Variant, Stanford Experts Say

Pamela Cruz. Peninsula 360 Press [P360P]

Currently, every day there are about 700 deaths in the U.S. due to COVID-19, which has significantly impacted the world. During the last few months, it has registered variations of the SARS-CoV-2 virus, which have proven to be stronger, faster and much more contagious, so experts suggest getting vaccinated against the disease as soon as possible, because, today, it is our only weapon to win the race against it.

Stanford University School of Medicine principal investigator Dr. Nirav R. Shah said that while it's a great happiness for the country that more than 100 million COVID-19 vaccines have been given, meaning that more than 75 million Americans have received at least one dose, "we can't start celebrating yet.

And the story of virus variation involves evolution and natural selection. "What happens is that the more virus particles there are, the more chances there are that, just by chance, a single virus particle is a little bit different from the rest, many of them with variation".

During a briefing held by Ethnic Media ServicesThe expert noted that, so far, the four variations of the virus that causes COVID-19 have started where there is high exposure to it, and in places with many infected people.

"One or more virus particles is all you need to make a slight change. Although vaccines are intended to stop the spread, those strains with selective advantages will spread faster and stronger.

"This is a race to see how quickly we get people protected, that is, fully vaccinated, versus the level of the disease in a community and its ease of transmission," he said.

Classifications and Definitions of SARS-CoV-2 Variants

Variant of Interest

Dr. Shah said that the variant of interest is one that has some changes in its genetic sequence, suggesting that it may be more contagious, that it may escape immunity, or that the type of immunity that is obtained from treatments and vaccination trials may not work as well against that variant.

"Today the CDC - Centers for Disease Control and Prevention - is looking at three variants of interest, the most common one they've heard of is the P2 variant - the Brazil strain - which was discovered in April 2020.

Of it, he said, actual transmissibility and lethality are still unknown. The other two variants of this type are B.1.53 and B.1.52, both first detected in November and December, respectively, in New York.

Variant of Concern.

The variant of concern has been shown to be more contagious and/or cause more severe disease.

It has a significant reduction in neutralization by antibodies generated during a pre-vaccination infection, reduced effectiveness of treatments or vaccines, or even diagnostic detection failures.

Therefore, the therapies being developed are less effective against this specific strain, he said, adding that people who have had one strain of COVID-19 can potentially be reinfected with a new strain. "That's very worrisome because today there are five of these variants of concern that are being tracked by the CDC," he said.

The best known strain is B.1.1.7 - the UK strain - and we know from research published to date, early studies show that it is transmitted from person to person 50 percent faster compared to some of the original strains.

He further specified that this strain can lead to increased mortality.

According to an article published March 15, he said, the antibody response to the Moderna and Pfizer vaccines is a little lower when you have this strain compared to previous strains, but it's still generally susceptible to those vaccines, as well as the Oxford-AstraZeneca and Novavax vaccines.

In the case of the B.1.3.5 variant - the South African strain - he noted that the vaccines continue to show good effectiveness, but more studies are needed to see the true impact.

These strains are joined by P.1 (Japan-Brazil) and B.1.43 (California, USA).

Variant of great consequence

Such strains, Dr. Shah said, cause more severe disease and more hospitalizations, and have been shown to defeat medical countermeasures.

According to the CDC, these types of strains have demonstrated diagnostic failure, and evidence suggests a significant reduction in vaccine effectiveness, a disproportionately high number of cases in which vaccines are ineffective, or very low vaccine-induced protection against serious disease, as well as a significant reduction in susceptibility to multiple approved or Emergency Use Authorization treatments in the country.

However, it should be noted that, so far, "there is no variant that meets this definition," nor has it been detected by the CDC.

"To win this race we have to focus on those 'variants' that are easiest to attack. And we have to get people vaccinated as quickly and broadly as possible," he said.

Similarly, he noted that several pharmaceutical companies are testing multivalent vaccines, creating different combinations to better target SARS-CoV-2 variants of the virus, similar to flu immunizations.

Group or Herd Immunity

For Dr. Nirav R. Shah, to reach "herd" immunity, 50 to 70 percent of people must already be resistant to existing strains, "if you're protected - vaccinated - you're not going to be a host for potential genetic variants to grow and that's an important level to reach".

However, he said there are a number of factors for that to happen. "First of all, we have seen that more than a dozen states are relaxing restrictions. So, for example, if you're not required to wear a mask, it's not surprising that a lot of people in a given state are not wearing masks. That's a problem, because what happens is that those are the public health measures that have been shown to work against the spread, because more people being infected means that we have a greater chance of variation.

He added that "there is a race" to vaccinate as many people as possible, with the goal of reaching that percentage of 60-70 or more.

And while it's true that no vaccine is perfect, the good news is that many of America's seniors are inoculated.

However, he said, one population that has been ignored and not effectively reached is the vulnerable homebound elderly, who have not been able to attend immunization appointments, go to hospitals or other places, or even register for immunization.

As of two weeks ago, the vaccination rate among homebound seniors was only 20 percent. "They're very vulnerable, so we need this level of herd immunity to protect those who are vulnerable and who are not protected by the vaccine for one or more reasons, and by fall we should be closer to that."

On the other hand, he stressed that, to date, none of the mutations or strains have completely escaped the major vaccines that exist. "Our hope is that with small modifications we can achieve a continuous evolution of the vaccines to match the evolution of the virus".

"The reality is, until the whole planet is vaccinated, we will achieve herd immunity. There will be pockets of people who haven't been vaccinated and the virus will survive, and that's all it takes. We know how fast it spreads.

An example of this is that if one of the unvaccinated people gets on a plane and exposes others who are part of the 20-30 percent who are also unvaccinated, there is a 70 percent chance that they will start another small cycle of infection and have to start all over again.

"It's a race around the world, we know that the virus doesn't respect any borders, so we should be as broad as possible in thinking about getting the vaccine to everyone.

For Dr. Dali Fan, clinical professor of health sciences at UC Davis, Johnson & Johnson's vaccine will be of great relevance in achieving herd immunity, not only because of its easy portability and single dose, but because from published clinical trial data, such immunization can provide, within 14 days of administration, 67 percent prevention of moderate to severe COVID-19 infections.

In addition, at 14 days it prevents 77 percent of severe COVID-19 infection, at 28 days that protection increases to 85 percent, and at 29 days, it provides 100 percent efficacy against severe cases.

He also noted that, at 28 days, the daily vaccine reduces hospitalization by 93 percent, 75 percent of the level of mortality, and at 10 weeks, it reduces a systemic infection by 75 percent.

All of this, coupled with easy transportation and storage, will be part of the formula for the vaccine to reach the least accessible places so that more people around the world can be immunized and finally achieve herd immunity, he said.  

Dr. Daniel Turner-Lloveras, of the University of Southern California, said it's still uncertain when all people will finally be able to walk the streets without masks.

"I don't think anyone we trust can say when that will happen, but we do know that herd immunity will most likely be achieved once we reach the threshold number of people vaccinated and so getting people vaccinated is extremely important and I think everyone will agree on that," he said.

He recalled that the rollout of the COVID-19 vaccine in the U.S. began under the administration of President Donald Trump, who decided that distribution should be up to the states and counties, which resulted in a lack of homogeneity.

"If we had been more unified, I think it would have helped a lot, especially with the black and Latino community, because now each state and county is coming up with their own method of providing culturally sensitive health information, some are making an excellent connection and some are not so much," she said.

Given this, he explained that it would be helpful if all levels of government could share resources in strategies to reach vulnerable populations, because the differences that are seen in terms of health have highlighted the digital divide that exists.

"I think it's a civil rights issue right now, we know that all the resources that are provided to people are now online. Minority communities are being left out in the rise of telehealth, in the race to sign up for vaccines, and unless we do something about it, they will continue to be left out and it will continue to contribute to the unequal distribution of COVID-19 vaccines."

Turner-Lloveras explained that, according to a recent report, 22 million elderly Americans do not have broadband Internet access at home -- that's 42 percent of the nation's population age 65 and older.

Before the pandemic, he said, 57 percent of Latino households said they owned a computer, and as the pandemic increased nearly 40 percent of Latinos did not have broadband Internet access at home.

He added that "this is a major barrier to access to education and health, and is one of the reasons why we started the Digital Companion Program.

The volunteer-led bilingual program teaches Latino community members how to use technology to open doors, including registering for immunization appointments. "Digital literacy, skills and empowerment are no longer just a nice to have, they are a necessity.

"One of the components is teaching them the skills and getting their digital literacy level to a point where they can not only sign up for vaccines, but also expand options for finding a job during and after the pandemic," she explained.

Those interested in the program can access it through the website https://lcac19.org/digital-companero/ or WhatsApp +1 (323) 607-8861.

For her part, Dr. Kim Rhodes of the University of California, San Francisco (UCSF) said that to bring the African-American community together to get tested for COVID-19 and help them access vaccines, the organization United in Health Oakland, of which she is a participant, has resorted to setting up pop-up clinics throughout Alameda County in California.

"In the vaccination phase, the Alameda County Public Health Department recognized that this was a significant advantage because we were able to reach 57 percent of African Americans with our testing resources."

He noted that 60 percent of those African-American participants were first-time COVID-19 testers, so the African-American community hopes that now, through COVID-19, they will be able to access vaccines.


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