An internal document from the Centers for Disease Control and Prevention (CDC) revealed the danger of the highly contagious COVID-19 delta variant, which is now spreading across the United States.

The Hill reported that The Washington Post obtained a slide presentation based on CDC's unpublished data, showing that the delta variant could cause more severe illness and spread as quickly as chickenpox, which is known to be one of the most contagious viruses.

The document came as CDC revised its mask guidance and reimplemented mask-wearing among fully vaccinated Americans in indoor public places at areas with high rates of COVID-19 infections, CNBC reported.

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CDC on COVID Delta Variant: 'The War Has Changed'

According to the document expected to be released on Friday, the delta variant of COVID also appears to spread quicker than the common cold, smallpox, SARS, Ebola, MERS, and the 1918 Spanish flu.

The CDC noted that only measles spread faster than the delta variant of the SARS-CoV-2 virus strain. The document also revealed that the delta variant, which originated from India, has a longer transmission window than the initial strain of the coronavirus and makes older people more at risk even though they were fully vaccinated.

The CDC document also underscored that fully vaccinated individuals could spread the delta variant just as easily as those who have not been vaccinated against the COVID.

"This document and some of the other information says you've got to be open to the possibility that Delta is worse than the number of ways and may upend some of our prior assumptions," said Dr. Robert Wachter from the University of California at San Francisco. Wachter reviewed the document from the CDC, according to CNBC.

Despite the dangers of the delta variant, CDC reiterated that the vaccine was still effective at protecting people from becoming sick and reducing the chance of hospitalization and death.

Health officials said that federal and state leaders should communicate to the public about the benefits of getting vaccinated, stressing that the COVID shot reduces the risk of death from the disease "10-fold or greater," and lower the risk of infection "three-fold."

Health officials noted that an individual infected with the delta variant carries up to 1,000 times more virus in their nasal passages than other strains. Thus, it resulted in higher transmissibility, even among the vaccinated.

New Study Says Vaccines Alone Won't Stop New COVID Strains

Meanwhile, a new study emphasized that vaccines alone cannot stop the delta variant and the emergence of new COVID strains. The study published in Nature Scientific Reports was conducted by researchers from the Institute of Science and Technology Austria.

The researchers noted that the vaccinations could accelerate the evolution of new COVID variants that evade their protection if safety measures like masking are halted prematurely.

The study said the coronavirus would not stop changing until almost everyone has been fully vaccinated. The researchers discovered that a fast rate of inoculation decreases the probability of the emergence of a resistant strain.

"Our results suggest that policymakers and individuals should consider maintaining non-pharmaceutical intervention and transmission-reducing behaviors throughout the entire vaccination period," researchers wrote in the study.

The CDC estimated that about 35,000 vaccinated people in the U.S. could get infected with the delta variant each week. However, the agency noted that most new infections occur among the unvaccinated.

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This article is owned by Latin Post

Written By: Joshua Summers

WATCH: Delta Variant Is As Contagious As Chickenpox, CDC Document Says - From TODAY