If you’re on the fence about getting the COVID-19 vaccine, you’re not alone. With no shortage of misinformation on the internet, it can be easy to feel unsure.

Feeling hesitant is understandable, but it slows the process of improving the health of our communities. So, we’ve addressed your top concerns about the vaccine to ensure you have the correct information and can feel confident in your choice.

Are the vaccines effective?

All of the COVID-19 vaccines are highly effective against COVID-19. Pfizer’s vaccine is proven to be 95% effective; Moderna’s is 94% effective; Johnson & Johnson’s vaccine is 72% effective. Typically, when a vaccine—the flu vaccine, for example—is 50% to 60% effective, it is considered successfully protective.

How can the vaccines be safe if they were developed so fast? The technology available today allows us to safely develop vaccines faster than 5-10 years ago. While the COVID-19 vaccines are new, the technology and methods used to develop them—messenger RNA (mRNA) and adenovirus—has been studied for years. This gave scientists an advantage to quickly develop the COVID-19 vaccines.

What’s in the COVID-19 vaccine?

The Pfizer and Moderna vaccines contain mRNA, and Johnson and Johnson’s vaccine contains an inactivated adenovirus.

The vaccines do not contain preservatives such as mercury or thimerosal, which many people have concerns about. They also do not contain eggs, latex, or antibiotics.

The mRNA in the vaccine does not stay in your body, and it cannot change your DNA.

Will the vaccine give me COVID-19?

No. The vaccine does not contain a live or weakened version of the virus, so it cannot make you sick. 

What are the side effects?

Many people have experienced side effects common with all vaccines, including

• Soreness or muscle aches
• Pain at the injection site
• Minor chills
• Low-grade fever

The side effects are short-lived and are normal signs that your body is building protection against the virus.

Less commonly, people have reported experiencing swollen lymph nodes after receiving the second dose, which clear up in 1-2 weeks in almost every case. Women who experience this side effect should still go to a mammogram appointment.

Fewer than one in every 1,000 people have an anaphylactic reaction, which is treatable.

If I have no side effects, did my vaccine work?

The severity of side effects is not proven to be related to vaccine efficacy. If you receive the vaccine, you are protected against the virus—regardless of the side effects you may or may not experience.

Do I need the vaccine if I’ve had COVID-19?

Immunity from vaccination will be more long-term than what would naturally follow after having COVID-19. Though immunity does occur after infection, we don’t know how long it lasts. Right now, estimates suggest anywhere around 6-9 months.