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Factsheet about the Delta Variant


Learn more about the the Delta Variant to protect you and your family


What is the Delta Variant?

Our understanding of the SARs COV-2 virus is changing rapidly. Viruses constantly evolve through mutation, producing new variants. Sometimes, the variants are more dangerous than the original. The Delta variant, also known as B.1.617, was first detected last year in India and now accounts for 80 percent of COVID cases in the U.S.  The Delta variant spreads faster than the original virus, and  data have shown that people infected with the Delta variant have 1000 times as much virus in their system when they test positive, making it easier to spread the virus to other people. 

Delta is having the greatest impact on the unvaccinated.

As case numbers rise and vaccination rates slow, states and communities with lower vaccination rates are seeing the fastest increase in COVID-19 — specifically cases of the Delta variant.  Recent data found that 99.5 percent of deaths from COVID-19 are now happening to people who have not gotten vaccinated.   

Reporting shows that more COVID cases resulting in hospitalization are occuring in younger populations than previously observed. Even children are ending up in the ICU.  Even though most young, healthy people recover from COVID-19, every infection carries a risk. Many young, healthy people have been hospitalized, have developed long term COVID-19 symptoms, or have passed COVID-19 to others. Many public health experts believe that nearly everyone who is unvaccinated will eventually get infected with the Delta variant. 

The symptoms of the Delta variant appear to be the same as the original version of COVID-19. However, physicians are seeing people getting sicker quicker, especially for younger people. The picture of the longer term effects of COVID are also becoming more clear. One in 10 people who get even mild COVID are ending up with long term health problems like chest pain, shortness of breath and extreme fatigue. Many of these people were young and healthy before they had COVID-19. 

Breakthrough Infections

No vaccine is 100 percent effective and breakthrough infections are to be expected. Typically, vaccinated people who contract the Delta variant are either asymptomatic or have very mild symptoms similar to the common cold such as cough, fever or headache, with the addition of significant loss of smell. 

As of July 26, 2021, there were 6,587 breakthrough cases that resulted in hospitalization or death among the 163 million people who are fully vaccinated — that's 0.00004 percent of vaccinated people. 

The Bottom Line

The COVID-19 vaccine can prevent nearly every case of COVID-19. We must continue to engage in robust outreach and education in communities with low or slowing vaccination rates, and ensure access and supports that ensure  every person can be vaccinated. Vaccine access must be truly equitable which includes paid time off for all who need it. Access to vaccines is only one element of a safe workplace. We must continue to engage in ongoing infection control and mitigation, ensure proper personal protective equipment (PPE) and advocate for paid leave, fair wages and access to healthcare for all essential workers.