The Centers for Disease Control and Prevention has strongly warned that the fight against coronavirus has changed. It now claims that even vaccinated persons may easily spread the virus.

A COVID-19 epidemic involving 469 cases began on July 3 in Provincetown, Massachusetts. A study titled "Outbreak of SARS-CoV-2 Infections, Including COVID-19 Vaccine Breakthrough Infections, Associated with Large Public Gatherings - Barnstable County, Massachusetts, July 2021" discovered that three-quarters of the infections occurred in persons who had been completely vaccinated. At the time of the research, roughly 69 percent of eligible individuals in the state had been vaccinated.

Hospitals In Southern California Continue To See Rise Of Covid-19 Cases
(Photo: Mario Tama/Getty Images)
LOS ANGELES, CALIFORNIA - JULY 30: (EDITORIAL USE ONLY) Registered nurse (RN) Elle Lauron cares for a COVID-19 patient in the improvised COVID-19 unit at Providence Holy Cross Medical Center in the Mission Hills neighborhood on July 30, 2021, in Los Angeles, California. The COVID-19 unit has been set up again to attend to a rise in COVID patients in a section of the hospital normally used for other purposes. The hospital had just five COVID patients last week but now is treating more than 25 amid a rise in COVID cases and hospitalizations in Southern California as the Delta variant continues to spread.

It also discovered no significant differences in viral load between breakthrough infections in completely vaccinated people and the other cases, suggesting that the viral load of vaccinated and unvaccinated coronavirus infected people is identical.

The CDC's decision to alter its mask recommendation was based on discovering that fully vaccinated persons can spread the infection.

How Fully Vaccinated People Could Spread Delta Strain

The CDC's director, Dr. Rochelle Walensky, said in a statement Friday that high viral loads indicate a higher risk of transmission. Hence, vaccinated persons infected with Delta can spread the virus, unlike with previous strains.

Bloomberg said the findings were attributed to the CDC's advice that fully vaccinated persons wear masks inside places where transmission is significant and high. Infections are on the rise across the United States, prompting the federal government and certain municipal governments to require employees to wear masks and, in some cases, vaccinations.

Walensky said the result is alarming, and it was a key discovery that led to the CDC's revised mask recommendation.

ALSO READ: COVID-19 Delta Variant Is 'More Infectious and Replicates Faster', New Study Might Reveal Why  

The report - initially published by The Washington Post - provides the scientific rationale behind the FDA's recent change in mask advice per NBC News.

The masking advice was modified to guarantee that the vaccinated population did not unintentionally spread the infection to others, particularly their unprotected or immunocompromised family members.

COVID-19 Vaccines Remain Effective in Protecting People From Death, Hospitalization

The good news is that COVID-19 vaccinations remain very effective in avoiding hospitalization and death from the virus. Three trials from Canada, Singapore, and Scotland, for example, revealed that the Pfizer vaccination protects against hospitalization and mortality by more than 90%.

The Provincetown epidemic, in fact, illustrates the vaccinations' efficacy.

Alex Morse, the town manager of Provincetown, tweeted on his official account there have been no deaths, only seven hospitalizations, and the symptoms are mostly minor among the 900 cases now connected to the cluster.

He added their positivity peaked at 15% on 7/15 and dropped to barely 4.8 percent as of writing. Morse added that the epidemic has been contained and that Provincetown is safe.

Due to the fast spread of the delta variant across the United States, the CDC has modified its mask recommendation, recommending that individuals wear masks within public places in regions where the virus is "substantial" or "high," regardless of vaccination status.

RELATED ARTICLE: Breakthrough Infections: What You Should Know When You Get Infected Even After Getting Vaccinated

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