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Top Vaccine Facts

This is what you need to know

All three vaccines have a very high level of effectiveness. Pfizer has a 95 percent rate and Moderna has a 94 percent rate. To be effective, both of these vaccines require two shots, given a few weeks apart. Vaccines cannot be mixed and matched between doses. The length of vaccine-induced immunity is not known at this time, and booster shots may be required.

The Pfizer and Moderna vaccines both use messenger RNA (mRNA) technology. They do not use any live virus particles, meaning individuals will not be exposed to the virus that causes COVID-19. Johnson & Johnson (J & J), is a viral vector vaccine. It is made from an inactivated adenovirus, the virus that causes the common cold, and contains a piece of DNA that instructs the body to make the COVID-19 spike protein. J & J used a modified adenovirus that can enter cells but can’t replicate inside them or cause illness.

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. 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. Reporting shows that more COVID cases resulting in hospitalization are occurring in younger populations than previously observed. Even children are ending up in the ICU. The COVID-19 vaccine can prevent nearly every case of COVID-19.

Learn more About the Delta Variant here.

Both Pfizer and Moderna utilized mRNA, which is easy to make in the laboratory, saving years in development and accelerating the creation of the vaccine. The Johnson & Johnson vaccine utilizes older technology used most recently to develop an ebola vaccine. This approach uses different viruses engineered to be harmless, but still capable of inducing your cells to make the proteins needed to create an immune response

If you have difficulty reaching a vaccination site, you may be able to get an in-home vaccination.

Contact these services to see if they offer in-home COVID-19 vaccinations in your area:

Your doctor or health care provider
Hotline for Medicare recipients at 1-800-633-4227 (TTY 1-877-486-2048)
Your state health department or call 211
Disability Information and Access Line (DIAL) 1-888-677-1199
Services for older adults and their families Eldercare Locator or 1-800-677-1116

You are fully vaccinated after two doses of Moderna or two doses of Pfizer or one dose of Johnson and Johnson. However, the CDC has recommended certain vaccinated groups receive a booster shot if they are at a higher risk of COVID transmission. Below are the CDC's recommendations:

For those who have taken the Pfizer-BioNTech vaccine at least six months ago, the CDC and FDA recommend boosters for the following:

  • Are 65+
  • 18+ AND
    • Live in long-term care settings
    • Have underlying medical conditions
    • Work or live in high-risk settings

For those who have taken the Moderna vaccine at least six months ago, the CDC and FDA recommend boosters for the following:

  • Are 65+
  • 18+ AND
    • Live in long-term care settings
    • Have underlying medical conditions
    • Work or live in high-risk settings

For those who have taken the Johnson and Jonhson vaccine at least two months ago, the CDC and FDA recommend boosters for the following:

  • Anyone 18+ who received the Johnson and Jonhson vaccine

You can mix and match boosters

Boosters are free.


Are there costs associated with vaccination?

No! your vaccine is free! The federal government is providing the vaccine free of charge to all people living in the United States, regardless of their immigration or health insurance status.

The CDC is also coordinating free rides and childcare for those getting vaccines. Find out more here.

Find a vaccine near you.


green map of USA with white state borders

Source: nashp.org

Vaccines.gov helps you find locations that carry COVID-19 vaccines and their contact information. Because every location handles appointments differently, you will need to schedule your appointment directly with the location you choose.