The recent increase in coronavirus cases in the U.S. amid ongoing vaccine hesitancy has led to many public health officials calling for states to reconsider their relaxing of COVID restrictions.

This comes as the U.S. is continuing its push to get more Americans vaccinated, as 58.1% of those at the age of 12 and older are fully vaccinated, according to CDC data, and 67.6% have received at least one dose. (Herd immunity is estimated to occur when 75% of any community has immunity.)

“We have made every possible effort reaching out to our communities to increase vaccination rates, but there’s a high degree of hesitancy in terms of getting new vaccinations accomplished,” Dr. Michael Gonzalez, a Texas-based emergency medicine physician, said on Yahoo Finance Live recently (video above). “So because of that, we really do have to turn to potentially more restrictive measures… I hate to start looking towards shutting down areas or public venues or things again but this particular strain is extraordinarily infectious.”

Even those who are fully vaccinated can transmit the Delta variant to others despite all three vaccines being very effective in preventing cases of serious illness and death. 

For unvaccinated people, the Delta variant is particularly dangerous. And the risk of lagging vaccination numbers is clear: The more the coronavirus spreads, the more opportunities for the virus to mutate into more contagious strains.

“I think if we don’t take these proactive measures, we’re going to be looking at wider measures that are going to be widely disruptive to both schools starting again in the fall as well as travel and resuming our lives,” Gonzalez said. “We had a great honeymoon period over the summer, but those of us in the clinical world watched COVID and Delta start exposing its strains and underlying infectiousness in other parts of the world and we’ve been holding up a caution sign, and now we really need to hold up a stop sign and say we really need to pay attention to this.”

Mascots walk through Times Square on July 22, 2021, as the Delta Covid surge is renewing calls for mask mandates in New York. - New York City will require public hospital workers to get vaccinated or take a weekly coronavirus test, Mayor Bill de Blasio said on July 21, as the metropolis faces an uptick in cases fueled by the Delta variant. (Photo by TIMOTHY A. CLARY / AFP) (Photo by TIMOTHY A. CLARY/AFP via Getty Images)Mascots walk through Times Square on July 22, 2021, as the Delta Covid surge is renewing calls for mask mandates in New York. - New York City will require public hospital workers to get vaccinated or take a weekly coronavirus test, Mayor Bill de Blasio said on July 21, as the metropolis faces an uptick in cases fueled by the Delta variant. (Photo by TIMOTHY A. CLARY / AFP) (Photo by TIMOTHY A. CLARY/AFP via Getty Images)

Mascots walk through Times Square on July 22, 2021. (Photo by TIMOTHY A. CLARY / AFP)

Delta variant: ‘We’re learning more about it every single day’

Some governors and local officials have already begun re-implementing — or at least strongly encouraging — mask mandates and establishing vaccine mandates.

Both New York Governor Andrew Cuomo and New Jersey Governor Phil Murphy are strongly encouraging their residents to wear masks indoors, though not going so far as to require them.

And both governors, along with California Gov. Gavin Newsom, are requiring their state employees to get the COVID vaccine. President Biden is also requiring it for federal employees, or else submit to coronavirus tests once a week.

“I think we are all pushing locally to try and make headway in terms of increasing restrictions,” Gonzalez said, adding: “I think all of us are extremely concerned at just how contagious this Delta variant appears to be. And we’re learning more about it every single day.”

According to the CDC, the Delta variant is as contagious as chicken pox, also known as varicella. Chicken pox is most common among children.

Michael Binparuis (15) of Nesconset, New York, is shown his dose of the Pfizer-BioNTech vaccine for the coronavirus disease (COVID-19) as children began receiving vaccinations at Northwell Health's Cohen Children's Medical Center in New Hyde Park, New York, U.S., May 13, 2021. REUTERS/Shannon StapletonMichael Binparuis (15) of Nesconset, New York, is shown his dose of the Pfizer-BioNTech vaccine for the coronavirus disease (COVID-19) as children began receiving vaccinations at Northwell Health's Cohen Children's Medical Center in New Hyde Park, New York, U.S., May 13, 2021. REUTERS/Shannon Stapleton

Michael Binparuis is shown his dose of the Pfizer-BioNTech vaccine as children began receiving vaccinations in New York, May 13, 2021. REUTERS/Shannon Stapleton

“The chickenpox example is something we’re all familiar with in childhood and even a passing contact was enough for certain people to get exposure to that,” Gonzalez said. “And that was the advent of the chicken pox parties people still talk about.”

With chicken pox parties, parents would allow their children to socialize together in order to purposefully infect their children, so that they would build immunity (a person can only contract chicken pox once). Some Americans floated a similar idea with the coronavirus, though this was met with backlash as it became clearer how much more dangerous COVID-19 is.

“We now know that this virus is more transmissible than any other variant that we’ve dealt with to date,” Dr. Mati Hlatshwayo Davis, an infectious disease physician, recently said on Yahoo Finance Live. “We are seeing this because of viral load data that has been received from outbreak investigations that the CDC had. That changes everything.”

‘There is protection in the vaccines that we have out there’

In some states, government officials are hoping to incentivize their residents to get the vaccine without having to revert back to restrictions. 

In Colorado, residents can now get $100 Walmart gift cards if they get vaccinated at certain locations throughout the state. Other states are offering college scholarships to students between the ages of 12-17 who get their COVID-19 vaccines.

President Biden recently called on state, territorial, and local governments to provide $100 payments to incentivize Americans to receive a coronavirus vaccine.

In any case, until vaccination rates improve, Gonzalez stressed that people should be encouraging those around them to get the vaccine and show them why they should no longer be hesitant about it.

“There is protection in the vaccines that we have out there,” he said. “Continue to mask up. I know that is frustrating and I know some people have said the CDC guidelines are confusing but their medicine is full of examples of things changing, treatments changing, as we learn and as we know more. So those are really the best things that we can do. Encourage people to get vaccinated, and really follow these new CDC guidelines to mask up indoors even if you’re vaccinated and to avoid high risk areas.”

Adriana Belmonte is a reporter and editor covering politics and health care policy for Yahoo Finance. You can follow her on Twitter @adrianambells and reach her at [email protected]

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