Reports of breakthrough infections from the Delta variant may have you wondering if the COVID-19 vaccines are still effective. The short answer: Absolutely.

Coronavirus Updates, Your Health | 8 days ago

Does the COVID-19 Vaccine Protect You Against the Delta Variant?

Reports of breakthrough infections from the Delta variant may have you wondering if the COVID-19 vaccines are still effective. The short answer: Absolutely.

This article was reviewed by Katie Passaretti, MD, medical director of infection prevention at Atrium Health and Anupama Neelakanta, MD, infectious disease physician at Atrium Health. 

The pandemic has introduced many of us to more information about viruses than we ever thought we’d need to know. Phrases like “contact tracing,” “incubation period” and “virus variants” have become part of our daily vocabulary.

And yet, as the virus continues to evolve, we – scientists and health experts included – continue to learn more about COVID-19.

The recent rise in COVID-19 cases across the United States has created new questions about how the vaccine protects people against the Delta variant.


Does the COVID-19 vaccine protect against the Delta variant?

The short answer: Yes. All COVID-19 vaccines currently authorized for use in the United States continue to be very effective against COVID-related severe illness and death.

The details: While they do not provide 100% protection against all COVID-19 infections, vaccines continue to significantly reduce the risk of getting infected, and are superb at preventing severe illness, hospitalization and death from COVID-19. Vaccines also protect our community and prevent overwhelming our healthcare systems with COVID-19 patients. 

Hospitals systems across the country, including Atrium Health, have been sharing data that supports this. At Atrium Health, 96% of our patients in the ICU on September 7, 2021, were unvaccinated. Similar statistics are true for patients nationwide.

Can someone who is vaccinated spread COVID-19?

The short answer: Yes – if they get infected. But vaccinated people appear to spread the virus at a lower rate than unvaccinated people. 

The details: For previous variants, lower amounts of viral genetic material were found in samples taken from fully vaccinated people who had breakthrough infections than from unvaccinated people with COVID-19. For people infected with the Delta variant, similar amounts of viral genetic material have been found among both unvaccinated and fully vaccinated people. However, like previous variants, the amount of viral genetic material may go down faster in fully vaccinated people when compared to unvaccinated people. This suggests fully vaccinated people will likely spread the virus for less time than unvaccinated people.

Why is the CDC recommending vaccinated people should continue to wear a mask?

The short answer: The Delta variant is more contagious than previous variants of COVID-19. Although vaccinated people spread it less, even the “small” action of wearing a mask can help in reducing the potential for spreading the disease.

The details: Due to high community transmission and the potential for vaccinated people to spread the virus, it is crucial to have safeguards in place to help reduce spread. This means having everyone who is able – including people who are vaccinated – wear masks indoors in public places. This also includes things we have been doing throughout the pandemic, including reducing the time we spend in crowds, keeping our distance from people we don’t live with, and wearing masks. 

While cases in the community are high, it’s important to do everything we can to help prevent the spread. Wearing a mask for now while improving vaccination rates can help slow the spread until more people are protected with the vaccine.

Why are some vaccinated people still getting very ill?

The short answer: The vaccine is highly effective against severe illness, but it is not 100% effective. Most people who are vaccinated and get infected will have mild or no symptoms, but some could get severely ill.

The details: It comes down to math. Millions of Americans are vaccinated, and that number is growing. This means that even though the risk of breakthrough infections is low, there will be thousands of fully vaccinated people who become infected and able to infect others, especially with the surging spread of the Delta variant. Among those infected, a small number will become severely ill. Many people we are seeing in our hospitals who are vaccinated usually have multiple comorbid conditions and are often immunocompromised. Vaccinated individuals most at risk for severe illness from COVID-19 are those with weakened immune systems or the very elderly.

The CDC and healthcare experts continue to monitor for the development of other variants, but the best way to prevent development is to improve vaccination rates and decrease spread of the currently widespread delta variant. 

Now that the Delta variant is here and other variants are being identified, should I bother getting vaccinated?

The short answerAbsolutely. The Delta variant is incredibly contagious, and vaccination is the best way to protect yourself, your family, and your community. 

The details: Our healthcare workers are seeing tragedy daily, watching their patients suffer in hospital beds from an illness that is now largely preventable. High vaccination coverage will reduce spread of the virus and help prevent new variants from emerging. In states with higher rates of vaccination, there are fewer hospitalizations and deaths from COVID-19.

The World Health Organization and the Centers for Disease Control continue to monitor other variants that are not yet widespread. While public health experts continue to research these variants, it’s important that we continue to manage the Delta variant. Which is why we continue to underscore the importance of the vaccine for everyone aged 12 years and older.

Learn more about the vaccine and where to schedule your vaccination.