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PROVIDENCE, R.I. - In a Zoom webinar for Brown University, medical experts discussed the prevalence of new variants of the novel coronavirus and what it means for the world’s attempts to return to normalcy as COVID-19 cases and hospitalizations across the U.S. surge while vaccination rates wane.
Dr. Ashish Jha, dean of Brown University’s School of Public Health, said by March 2021 he had a strong dose of optimism about the course of the global COVID-19 pandemic.
"If we were speaking in mid-June, things looked really good. In fact, numbers were way down. Vaccinations were continuing to climb," Jha said.
Jha said he can list two factors that have caused the trajectory of the pandemic to veer differently than he expected. The first is the rise of the delta variant and how contagious it has turned out to be.
"I don’t think we had quite the sense of just how much more contagious it was, how different it was acting from a population spread point of view," Jha said.
The second — and arguably most surprising — factor, Jha said, is the skepticism surrounding the COVID-19 vaccines.
"I did not think that we’d be at a point where a third of American adults would basically look at the last year and a half, look at the fact that we have these incredible vaccines that are available and widely available, easy to get, free, and say ‘no thank you,’" Jha said.
Jha explained that a large unvaccinated population mixed with a super-contagious variant of the novel coronavirus is a dangerous combination.
While data on breakthrough cases is fairly inconclusive, Jha said it’s a third factor that could contribute to the continuation of the COVID-19 pandemic, which has now claimed the lives of more than 618,000 Americans.
"So put all those together, we’re in a much worse situation than where I thought we would be four months ago," Jha said. "It’s a reminder that one has to be humble about these things."
According to recent data from the U.S. Centers for Disease Control and Prevention on breakthrough COVID-19 cases, less than 1% of people who have contracted the novel coronavirus despite being vaccinated have either been hospitalized or died.
RELATED: CDC: Less than 1% of breakthrough COVID-19 cases led to hospitalization or death
As of July 26, the CDC reported that 163 million Americans had been vaccinated for COVID-19. Out of those inoculations in the same timeframe, 6,587 Covid-19 breakthrough cases occurred that either resulted in hospitalization or death.
While hospitalizations and deaths from breakthrough cases appear to be extremely rare, the CDC is not currently tracking all breakthrough cases, leaving a huge gap of data that could allow medical experts to better understand the impact of breakthrough cases on the pandemic.
In an email to FOX TV Stations on Aug. 3, a CDC spokesperson said, "On May 1, 2021, CDC transitioned the national reporting system to focus on vaccine breakthrough cases in patients who were hospitalized or died. This shift will help maximize the quality of the data collected on cases of greatest clinical and public health importance."
Despite the emergence of breakthrough cases, the CDC said vaccines are still the most effective tool at fighting the spread of the disease and it is critical that all people who are eligible get vaccinated as contagious and potentially deadlier mutations of the virus continue to emerge and circulate.
RELATED: CDC urges COVID-19 vaccinations for pregnant women amid delta surge
"The vaccines are safe and effective, and it has never been more urgent to increase vaccinations as we face the highly transmissible delta variant and see severe outcomes from COVID-19 among unvaccinated pregnant people,’’ CDC Director Dr. Rochelle Walensky said in a statement when the CDC urged all pregnant women to get vaccinated against COVID-19 on Wednesday.
Echoing Walensky’s sentiment, Jha tweeted on Aug. 9 that on that day in the five most vaccinated states consisting of 14 million people, 580 were hospitalized while 12 died. In the five least vaccinated states consisting of 16 million people, more than 6,000 people were hospitalized while 104 died.
"Per capita, least vaccinated states have 10X hospitalizations and 7X deaths So yeah, vaccines are working," Jha wrote.
Speaking with Jha, Dr. Paul Offit, director of the Vaccine Education Center at Children’s Hospital of Pennsylvania and a member of the FDA Vaccine Advisory Panel, said it’s clear the delta variant is more dangerous due to the amount of viral material it sheds compared to earlier variants.
He explained that because the delta variant sheds so much more of its material, it takes much less contact to spread the disease.
And Offit’s assertions about the transmissibility of the delta variant are backed up by research.
A recent study published on July 7 and led by Chinese epidemiologist Jing Lu at the Guangdong Provincial Center for Disease Control and Prevention in Guangzhou, China shed light on why the delta variant is of grave concern to the world’s health care system and why it is more transmissible than other mutations.
Study authors noted that one characteristic that makes the variant so worrisome is its high viral load.
Researchers found that the delta variant contains 1,000 times more viral material than that of the original novel coronavirus variant that infected much of the global population during the onset of the global pandemic last year.
More concerning is recent CDC data which indicates that even fully vaccinated people can transmit the delta variant to others, given the strain’s high viral load.
"We are actively conducting outbreak investigations of what’s occurring in places that are having clusters... What we’ve learned in that context, is when we examine the rare breakthrough infections and we look at the amount of virus in those people, it’s pretty similar to the amount of virus in unvaccinated people," Walensky said, speaking to reporters on July 27 when the health agency issued new recommendations that vaccinated people return to wearing masks indoors in parts of the U.S. where the virus is surging.
Offit said he’s amazed at how much of society appears to have returned to normal behaviors despite the pandemic being far from over. He said last year most people were "good about masks and social distancing," and now "there’s 40,000 people at a Phillies game and people are having weddings and birthday parties and we’re just getting together much more than we did last year."
With all factors taken into consideration, both Offit and Jha were asked what the near-term future might look like.
The short answer from both was: "We don’t know."
Jha said much can be learned from countries that have been devastated by the virus, including India, where the delta variant first emerged. "When the numbers got catastrophically bad and when hospitals ran out of oxygen, people changed their behavior in very radical ways," Jha said.
Jha estimates that the U.S. could see a peak of the virus in late August and into September, followed by a decline that he thinks will vary from state to state.
Offit worries that such a large percentage of people who have still yet to be naturally infected with the disease and build up antibodies and unvaccinated individuals combined with the way people are behaving could spell disaster.
Because of the transmissibility of the delta variant, Offit said the U.S. would need to vaccinate 80-90% of the population, but said it could take a while to get there.
With such an alarmingly high population of people refusing to take the vaccines, Offit said it’s imperative to get messaging out to the public compelling them to "do the right thing" and get vaccinated.
This story was reported from Los Angeles. The Associated Press contributed.