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Tuesday, Aug. 17, 2021

Is the delta coronavirus variant challenging some of the protective effects of COVID-19 vaccines?

Austin Tannenbaum, Gigafact
yes

Vaccines appear to be less effective at slowing the spread of the coronavirus’s delta variant, contributing to increased caseloads and a greater risk of contracting symptomatic COVID-19, even among the vaccinated. 

The American Society of Microbiology estimates that the delta variant is “40%-60% more transmissible than the alpha [variant] and almost twice as transmissible as the original…strain." The ASM outlined related challenges posed by delta, including:

Higher viral loads, causing greater contagiousness.Antibodies that are less able to neutralize the virus.Slightly less protection against symptomatic “breakthrough” disease for the vaccinated.

Delta is currently responsible for 83% of U.S. coronavirus infections. Infections that cause severe symptoms increase the chance of mutations into other variants, leading public health leaders and scientists to urge continued efforts to increase vaccination rates.

Vaccinated people continue to be well-protected against serious disease and death.

This fact brief is responsive to conversations such as this one.

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