***This page has not been edited to reflect the updated ’25-’26 COVID vaccine, but is still great general information. Stay tuned for updated information reflecting changes regarding this season’s vaccine. You may find the NYS COVID-19 Guidance Repository helpful in the meantime.

The most common questions we’ve received from community members and parents in the Ithaca area, answered by Cornell University scientists from Vaccination Conversations with Scientists

How is the updated 2024-2025 vaccine different from the original?

As the COVID-19 virus spreads, it has a chance to change. These changed or mutated versions of the virus are called variants. Some variants allow the virus to spread more quickly or make it resistant to treatments or vaccines. Scientists developed the 2024-2025 COVID-19 vaccine to protect against the variants most people were getting sick with (the XBB lineage of the Omicron variant), which is distinct from the original version of the vaccine.

Scientists can easily change the vaccine’s target variant by changing the sequence of the mRNA ingredient in the vaccine, without having to develop a whole new formula. The mRNA contains the sequence of information your body needs to train your body to recognize the COVID-19 virus when you are exposed to it. Each shot contains small amounts of mRNA along with fats, salts, sugars, and acids to help protect the mRNA and keep the vaccine shelf stable. The updated vaccine has been tested by clinical trials to ensure safety.

Will we need to keep getting a new vaccine every year?

As time goes on and different variants of the COVID-19 virus are discovered, the vaccine will need to be updated to make sure we are fully protected, similar to how the seasonal flu vaccine is updated every year.

If my child has already had COVID-19, should they still be vaccinated?

It is still recommended to get the updated 2024-2025 COVID-19 vaccine. You may decide to wait up to 90 days after infection for long-lasting protection, because it is uncommon to get COVID-19 again within 3 months of infection. Repeat infections of COVID-19 have been shown to have increased severity of symptoms, so protecting your child now with the COVID-19 vaccine can benefit their future health.

What should I expect when myself or my child gets vaccinated?

Vaccinated people may experience mild side effects for a day or two. They may have a sore arm, feel achy and tired, or have a mild fever and chills.

Are the COVID-19 vaccines safe?

We’ve come a long way since 2020, when the COVID-19 vaccines were first released under Emergency Use Authorization. But now, over 1 billion vaccine doses have been given to Americans, including doses to 2.2 million kids ages 6 months-4 years, 11.2 million kids ages 5-12, and 17.9 million adolescents ages 12-17. Because so many people have received the COVID-19 mRNA vaccines, we have the ability to monitor for side effects that would be incredibly rare.

How do scientists study vaccine safety?

The FDA reviews large studies called clinical trials where thousands of kids were given the vaccine and side effects were followed over time, which is standard practice for all vaccines and prescription medications. For example, for the Pfizer 2023-2024 COVID-19 vaccine clinical trial, 4600 kids ages 5-11 were studied, where 3100 kids were given the vaccine and the rest were given a placebo (non-vaccine) control. After the second dose, they found that the vaccine was 91% effective in preventing COVID-19 by comparing kids who did get vaccinated to kids who didn’t, and 100% effective in the 12-17 age group. For younger children (6 mo. to 4 years), the children were fully vaccinated and then their immune responses were found to be comparable with young adults given higher adult doses of the same vaccine, and their safety was monitored over time. 

Are there long term side effects?

Side effects of the COVID-19 vaccine are taken incredibly seriously, and are documented by doctors reporting cases to VAERS (Vaccine Adverse Event Reporting System). With the Moderna and Pfizer vaccines, the most serious side effect observed was myocarditis, a treatable heart condition that was mild in a majority of cases. This was only observed in about 1 in 1 million people–your child has nearly double the chances of becoming an olympic gold medalist (1 in ~600,000). 

When you get vaccinated, the vaccine itself is short-lived, being broken down by your body within a few days. The vaccine itself does not stay with you, only the long-lasting immunity learned from it by your body.

Vaccinate now to protect your child from possible effects of COVID-19 infection.

No kid wants to be sick, and even mild COVID-19 infection can keep your child from going to school and doing their best. Additionally, while most people who contract COVID-19 feel better within a few days or weeks, 1.3% of American children have had new, returning, or ongoing symptoms that were not present prior to COVID-19 infection, referred to as Long COVID. These symptoms present differently in kids than adults, and may include inability to tolerate physical activity, chest tightness, anxiety, difficulty breathing, difficulty thinking (brain fog), or weight loss due to loss of sense of taste. Children can also be susceptible to heart damage after severe COVID infection, which can be difficult to identify in young children. Vaccination against COVID-19 is the best way to avoid these potential serious complications due to COVID-19 infection.