New COVID-19 Vaccines From Pfizer and Moderna: What You Need to Know

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It's that time of year again. A new round of COVID vaccines is on the way to Americans.

Last week, the Food and Drug Administration approved updated mRNA-based vaccines from Pfizer and Moderna With a relatively large spike in virus cases over the summer, here's what you need to know, including how the vaccines are different this time around, who's eligible, where to get vaccinated and more.

U.S. health officials have long told patients to expect annual updates to COVID-19 vaccinations, as the virus mutates into new strains that can evade the immunity people gain from vaccinations or previous infections. That’s similar to how the U.S. rolls out new flu vaccines each year.

This time, the vaccines from Pfizer and Moderna are designed to target a strain called KP.2, a variant of the highly contagious Omicron JN.1 strain that began spreading widely in the United States earlier this year.

The KP.2 strain was the dominant strain of the virus in May, but it now accounts for only about 3% of all cases in the United States as of Aug. 17, according to the latest data from the Centers for Disease Control and Prevention.

However, both Pfizer and Moderna have said their new vaccines can produce stronger immune responses against other circulating variants, such as KP.3, than last year's round of vaccines that targeted the Omicron XBB.1.5 strain.

The KP.3 strain accounts for about 17% of cases in the United States, while a related strain called KP.3.1.1 accounts for about 37% of cases, according to data from the Centers for Disease Control and Prevention.

“The good news so far is that the updated vaccine closely matches the KP.3 family of viruses that continues to grow in dominance,” Mandy Cohen, director of the Centers for Disease Control and Prevention, told reporters during a briefing on Friday.

The Centers for Disease Control and Prevention recommends that everyone 6 months of age or older receive one dose of the new COVID vaccine.

To achieve maximum protection, people should wait at least two to three months since their last vaccination or COVID infection before getting one of the updated shots, Dr. Peter Marks, director of the FDA's Center for Biologics Evaluation and Research, told NPR last week.

Health officials also stressed the importance of continuing to vaccinate vulnerable individuals against COVID-19, including people 65 and older and those with weakened immune systems or serious medical conditions.

After last week's approval, Pfizer and Moderna said they expect their new vaccines to be available in pharmacies, hospitals and clinics across the United States “in the coming days.”

Walgreens said patients can now schedule vaccination appointments in stores nationwide, according to a statement Thursday. The company said appointments are available for people ages 12 and older starting Sept. 6.

Meanwhile, CVS's online vaccine scheduling program is offering appointments as early as Wednesday. Rite-Aid's vaccine scheduling program is offering appointments as early as September.

The Centers for Disease Control and Prevention plans to relaunch its vaccine appointment site once it becomes more widely available.

The FDA's Marks told NPR he's likely to get vaccinated “as soon as possible” because the variant targeted by the updated shots is “reasonably close” to the strains currently circulating in the U.S.

But he said some people might consider waiting until September or October if they want to maximize their protection from the vaccine during a potential COVID-19 surge in the winter and holiday season.

“It seems like getting vaccinated in September to early October is a very reasonable idea to help protect you through the December to January time period,” Marks told the newspaper. “It doesn’t stop suddenly. It’s not like something that suddenly stops after three or four months. It’s just that immunity will decline over time.”

Most private insurance plans, as well as the federal Medicare and Medicaid programs, cover the cost of COVID vaccines.

Children can also get free vaccines through a federally funded program called Vaccines for Kids.

Meanwhile, the Centers for Disease Control and Prevention's Bridge Access program, which was designed to provide free Covid vaccines to uninsured or underinsured Americans, will not reopen this year.

But the Centers for Disease Control and Prevention has found $62 million to fund state and local immunization programs to cover the cost of COVID vaccines for uninsured or underinsured adults, Dr. Demeter Daskalakis, director of the CDC’s National Center for Immunization and Respiratory Diseases, told reporters during a briefing last week.

Novavax Intel has applied for a license for a new protein-based vaccine targeting the JN1 strain. The company said its vaccine would protect against strains of this strain, such as KP2.3, KP3, KP3.1.1, and LB1.

In a statement last week, Novavax said it was working “productively” with the FDA as the agency completes its review. Novavax expects its vaccine to be authorized in time for the U.S. vaccination season.

Feel free to send any tips, suggestions, story ideas or data to Annika at annikakim.constantino@nbcuni.com.

Earlier this month, I started testing a new continuous glucose monitor from Diabetes Management. DexcomCalled Stelo, it's the company's first product available without a prescription.

A continuous glucose monitor, or CGM, is a small sensor inserted through the skin that measures glucose levels in real time. Glucose is a type of sugar that people get from carbohydrates and is the body's primary source of energy.

Everyone's glucose levels fluctuate, but high levels can lead to serious health problems like diabetes, heart disease, and kidney disease over time. Continuous glucose monitors are often prescribed to people with diabetes so they can monitor their glucose levels and get alerts in case of an emergency.

Stelo is primarily designed for adults with type 2 diabetes or prediabetes who don’t use insulin, though people without either condition can also get it. The device launched in the U.S. on Monday after being approved by the Food and Drug Administration in March.

Users can purchase a month’s supply of Stelo online for $99, or sign up for an ongoing subscription for $89 per month. Dexcom said patients can also use flexible spending accounts and health savings accounts to pay for it. Dexcom is working with Amazon to fulfill Stelo delivery orders.

I have been using this sensor for a few weeks now and have learned a lot already. I think it is an easy product to use for an easy introduction to understanding your glucose data.

Once the sensors arrive at your home, you’ll find everything you need in the box. First, attach the sensor to your arm and pair it with the Stelo app.

The app walks you through exactly what to do, so don’t worry. I cleaned the back of my right arm, placed the Dexcom applicator there, pressed the button, and the sensor went to work right away. There’s a small needle on the applicator that can feel a bit uncomfortable, but I didn’t feel anything.

The CGM connects to the Stelo app via Bluetooth, and then takes about half an hour to warm up.

When I first got to this step, I had a few issues. As soon as my device started to warm up, I got an error message that said “sensor short.” The message told me not to remove the CGM, and said the problem would resolve in three hours. I left it on for the rest of the day, but by evening, I noticed some light bleeding around the sensor.

I decided to remove the CGM, which you can do by peeling it off like a sticker. I tried again with a new sensor on my other arm, and it warmed up and worked properly. I no longer had any bleeding issues. If you have any issues with the Stelo while using it, you can message the chat feature on the site to ask questions or get a replacement device if needed.

Overall, I found the sensor to be very easy to wear. It’s waterproof, and it lasts for 15 days at a time (a new record for Dexcom). It’s gray, about the size of a quarter, and about a half-inch thick. While it did occasionally get stuck when I was wearing long sleeves, I felt like I could wear anything over it. I didn’t notice it while I was sleeping, either.

I also found the Stelo app interface to be easy to use, and I think Dexcom does a good job of presenting the data in a way that doesn't seem overwhelming or confusing.

On the Stelo app home page, you’ll see your most recent glucose reading, which is updated every 15 minutes. You’ll also see a graph of your readings each day, which includes a shaded green area to indicate your “goal range.” This range is the range that Dexcom encourages users to try to maintain their glucose levels, based on current medical standards.

Next to the home page is the “Events” page, where you can log meals, activities, finger pricks, another way to measure your blood sugar, or other notes. You don’t need to log every little detail of your day, but Jake Leach, Dexcom’s chief operating officer, told me it’s important to do so when you’re experiencing a glucose spike.

Glucose spikes occur when the amount of sugar in your bloodstream rises rapidly and then drops. This often happens after eating. Stelo will let you know when you experience a significant glucose spike, and keeping an entry can help you think about what might be causing it, Leach said.

If this is your first time using a CGM, I definitely recommend reading the articles in the Learn tab of the app. They are short, and help break down concepts like what glucose is, what it affects, and why it is important.

In just two weeks, I’ve learned a lot about how my body responds to food and activity using Stelo. Now that this technology is available without a prescription, I wouldn’t be surprised if CGMs become the next wearable technology in the U.S.

Feel free to send any tips, suggestions, story ideas or data to Ashley at ashley.capoot@nbcuni.com.