A new Centers for Disease Control and Prevention (CDC) study showed that the effectiveness of the COVID vaccines against the highly transmissible Delta variant has dropped.

The study published Tuesday noted that the vaccine has reduced its effectiveness from 91 percent to 66 percent against the Delta variant that now accounts for most COVID cases, KSLA reported.

However, the study also showed that the vaccine still cuts your risk by two-thirds against the Delta variant. Thus, vaccinated people are still less likely to get infected and far less likely to get severely ill if they contract the virus. 

The study, known as HEROES-RECOVER, includes more than 4,000 health care workers, first responders, and other frontline workers in eight areas through six states. All of them were tested weekly for COVID infection. More than four in five were vaccinated, and most of them received the mRNA vaccines from either Pfizer or Moderna.

During the initial study period from December 14, 2020 to April 10, 2021, vaccine effectiveness was estimated at 91 percent. But during weeks in the run-up to August 14, when the Delta variant became dominant, the effectiveness fell to 66 percent.

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COVID Vaccines Effectiveness

According to a Stat News report, other studies trying to show the effectiveness of the vaccines in preventing infections have also generally shown reduction against the Delta.

CDC earlier advised vaccinated people that they no longer needed to wear masks. However, the spread of the Delta variant was causing breakthrough infections.

Scientists had concluded that vaccinated people who have been infected with Delta could spread the virus to others, though not as infectious as unvaccinated people.

The spread of Delta has prompted CDC to recall their decision on mask requirement, encouraging even vaccinated people to wear masks.

Ashley Fowlkes, an epidemiologist on the COVID-19 response team at the CDC, said they're trying to determine if it is Delta variant or waning effectiveness. But Fowlkes said they concluded that they could not really tell. Fowlkes noted that 66 percent effectiveness is a really high number, The New York Times reported. 

Those who had been hospitalized despite being vaccinated were older on average. At the same time, the death rate was also lower among the vaccinated, with 0.2 percent compared with 0.6 percent among the unvaccinated.

The Delta Variant

The Delta variant is identified to be more than twice contagious as previous variants. Some data also showed that the variant might cause more severe illness than previous strains in an unvaccinated population, according to the CDC.

Vaccinated people infected with the Delta variant also appear to be infectious for a shorter period. The Delta variant also seems to have the same high amount of virus in both unvaccinated and vaccinated.

However, fully vaccinated people's infections go down faster than infections in unvaccinated people. Symptoms of Delta variant among vaccinated people include headache, sore throat, and loss of smell.

The symptom of coughing or shortness of breath has been missing with vaccinated people. However, Dr. Jack O'Horo, a critical care and infectious diseases specialist at the Mayo Clinic, said the symptoms still really remained the same.

O'Horo noted that they are still looking at initially cold-type symptoms like cough and fever.

READ MORE: Moderna Booster Shots Work Well Against Variants: Early Data 

This article is owned by Latin Post

Written by: Mary Webber

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