• Home
  • Latest
  • Fortune 500
  • Finance
  • Tech
  • Leadership
  • Lifestyle
  • Rankings
  • Multimedia
HealthCoronavirus

The ‘Kraken’ COVID variant taking hold in the U.S. Here’s how many vaccine shots there are—and what experts recommend to protect yourself

By
Alexa Mikhail
Alexa Mikhail
Senior Reporter, Fortune Well
Down Arrow Button Icon
By
Alexa Mikhail
Alexa Mikhail
Senior Reporter, Fortune Well
Down Arrow Button Icon
January 10, 2023, 4:04 PM ET
It's still early to say with certainty how well the vaccine will work against "Kraken," derived from Omicron, but experts believe it will likely be generally as effective as other variants.
It's still early to say with certainty how well the vaccine will work against "Kraken," derived from Omicron, but experts believe it will likely be generally as effective as other variants.FREDERIC J. BROWN—AFP/Getty Images

Another highly contagious COVID-19 variant called XBB.1.5 has made its way to the U.S. with the World Health Organization (WHO) calling it “the most transmissible” variant to date. 

Coined “Kraken” by a Canadian biology professor, the new variant is laying down roots in the U.S, although the U.S. Centers for Disease Control and Prevention (CDC) have had some wavering data on how many cases “Kraken” has caused. It now estimates that the variant will make up over a fourth of total cases this week. 

“That doesn’t mean the variant will cause more or less severe disease than previous versions of COVID,” says Dr. Charles Miramonti, a senior medical director at Oak Street Health in Indianapolis, Indiana. “But it does spread more effectively than previous strains.” 

As talk of a winter surge looms, you may be wondering about your level of immunity and if you can evade infection by yet another strain. Now that it’s been over two years since the authorization of the first COVID-19 vaccines, followed by booster rollouts, you may be confused about how many COVID shots there are out there, and whether you are protected. 

How many COVID shots have there been?

Health officials have recommended four shots to most people, Miramonti says. 

Four types of COVID-19 vaccines have been made available in the U.S: Pfizer-BioNTech, Moderna, Novavax, and Johnson & Johnson. Johnson & Johnson’s is a single-dose vaccine, but all others are a two-dose regimen. These doses are part of the primary, or initial, series of vaccines against the virus. 

Due to immunity waning over time, booster shots became available to keep people continuously protected. Pfizer and Moderna offered a booster to their m-RNA vaccines in the fall of 2021. In the fall of 2022, they also offered a bivalent booster, which specifically targets the Omicron sub-variants that have dominated the country. 

Johnson & Johnson’s original dose has since been limited to people who clinically cannot get the Pfizer or Moderna vaccine or for those who would otherwise forgo vaccination. If you had their single-dose vaccine, you were eligible for both boosters from Pfizer or Moderna.

Novavax, which was authorized for use in the U.S. much later than the others and isn’t as commonly used, has a booster. While it’s not an updated bivalent booster, it’s thought to potentially offer broader protection. Its manufacturer says its original formula offers protection against several COVID strains, including Omicron BA.5, according to Yale Medicine.  

If you’re older and/or moderately or severely immunocompromised, you may have received up to two additional “booster” doses of the original vaccine, in addition to a dose of the updated Omicron vaccine this fall. People over 50 have also been eligible for an additional booster as of spring 2022.  

These are the three most common COVID vaccines and the number of shots associated with them 

The two-dose Moderna Vaccine

  • 4 shots: two shots for the primary dose, one booster which became available in the fall of 2021, and the new bivalent booster available as of September 2022
  • Some people may have 5 shots if they are over 50 or immunocompromised 

The two-dose Pfizer Vaccine

  • 4 shots: two shots for the primary dose, one booster which became in the fall of 2021, and the new bivalent booster available as of September 2022
  • Some people may have 5 shots if they are over 50 or immunocompromised 

The one-dose Johnson & Johnson vaccine

  • 3 shots: one shot for the primary dose, and two boosters from Moderna or Pfizer when they became authorized in the Fall of 2021, and then in 2022 respectively. The CDC says mixing and matching works fine for people in this category.
  • Some people may have 4 shots if they are over 50 or immunocompromised 

There are some nuances to how many vaccines and boosters are generally available. Some people with weakened immune systems qualify for an additional dose, which works to “improve immunocompromised people’s response to their initial vaccine series,” according to Johns Hopkins Medicine.

Do the boosters help against new variants? 

Experts explain that while new variants can be immune-evasive, getting vaccinated and boosted is the best way to stay protected from infection and getting severely ill. It’s still early to say with certainty how well the vaccine will work against “Kraken,” derived from Omicron, but experts believe it will likely be generally as effective as other variants.

It is not too late to get the bivalent booster, which will be the most effective booster against the current strains from getting severely sick, says Dr. Preeti Malani, an infectious disease specialist at the University of Michigan. 

“The name of the game is to not get hospitalized if you’re vulnerable,” she says. 

For those who want a bivalent booster, you must be at least two months past your primary series. If you have recently had COVID and want to get the bivalent booster, consider delaying your appointment by three months from the onset of symptoms or a positive test. 

The more a variant circulates in a community, the more it can mutate and evade immunity from both vaccination and prior infection. Since getting vaccinated can help reduce the spread of the virus, getting as many people as possible vaccinated in a community minimizes the chance of new variants developing.

“Updated COVID-19 boosters can help restore protection that has decreased since previous vaccination,” the CDC says. 

Do you need another COVID booster?

There is not a new booster that is targeting “Kraken” as of now. Experts instead point to the low rates of vaccination and booster vaccination for the already available ones.

The vast majority of children have not been vaccinated at all, per data from November from the CDC. In a survey from Morning Consult conducted in November, nearly half of U.S. adults who are vaccinated and did not receive a booster from September to November said they do not plan to get the bivalent one, many people citing that they don’t have time to get one or don’t see the point. 

As the variants change, vaccine fatigue and, now, booster fatigue, has set in, but remaining up-to-date on vaccines and boosters that are authorized can help you do your part in limiting the spread. 

“The newest boosters are still saving lives and keeping people out of the hospital,” Miramonti says. “They’re keeping secondary infections to a minimum,” adding they protect people against longer-term complications from COVID that can weaken the immune system. 

About the Author
By Alexa MikhailSenior Reporter, Fortune Well
LinkedIn iconTwitter icon

Alexa Mikhail is a former senior health and wellness reporter for Fortune Well, covering longevity, aging, caregiving, workplace wellness, and mental health.

See full bioRight Arrow Button Icon

Latest in Health

Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025

Most Popular

Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Fortune Secondary Logo
Rankings
  • 100 Best Companies
  • Fortune 500
  • Global 500
  • Fortune 500 Europe
  • Most Powerful Women
  • Future 50
  • World’s Most Admired Companies
  • See All Rankings
Sections
  • Finance
  • Fortune Crypto
  • Features
  • Leadership
  • Health
  • Commentary
  • Success
  • Retail
  • Mpw
  • Tech
  • Lifestyle
  • CEO Initiative
  • Asia
  • Politics
  • Conferences
  • Europe
  • Newsletters
  • Personal Finance
  • Environment
  • Magazine
  • Education
Customer Support
  • Frequently Asked Questions
  • Customer Service Portal
  • Privacy Policy
  • Terms Of Use
  • Single Issues For Purchase
  • International Print
Commercial Services
  • Advertising
  • Fortune Brand Studio
  • Fortune Analytics
  • Fortune Conferences
  • Business Development
  • Group Subscriptions
About Us
  • About Us
  • Editorial Calendar
  • Press Center
  • Work At Fortune
  • Diversity And Inclusion
  • Terms And Conditions
  • Site Map
  • About Us
  • Editorial Calendar
  • Press Center
  • Work At Fortune
  • Diversity And Inclusion
  • Terms And Conditions
  • Site Map
  • Facebook icon
  • Twitter icon
  • LinkedIn icon
  • Instagram icon
  • Pinterest icon

© 2026 Fortune Media IP Limited. All Rights Reserved. Use of this site constitutes acceptance of our Terms of Use and Privacy Policy | CA Notice at Collection and Privacy Notice | Do Not Sell/Share My Personal Information
FORTUNE is a trademark of Fortune Media IP Limited, registered in the U.S. and other countries. FORTUNE may receive compensation for some links to products and services on this website. Offers may be subject to change without notice.


Latest in Health

HealthDietary Supplements
The Best Colostrum Supplements 2026: Tested and Approved
By Emily PharesMarch 24, 2026
1 day ago
Personal FinanceTaxes
Americans spend $146 billion and 11.6 billion hours doing their taxes, and most of it is just filling out paperwork
By Catherina GioinoMarch 24, 2026
1 day ago
fauci
CommentaryCOVID-19 vaccines
How COVID turned America against science — and what it will take to win it back
By David Blumenthal and James A. MoroneMarch 24, 2026
2 days ago
MagazineSocial Media
Inside the Seattle clinic that treats tech addiction like heroin, and clients detox for up to 16 weeks
By Kristin StollerMarch 24, 2026
2 days ago
US President Donald Trump speaks to reporters before boarding Air Force One at Palm Beach International Airport in West Palm Beach, Florida, on March 23, 2026.
HealthIran
Trump has TACO’d again, this time in Iran, sparking a $1.7 trillion stock market rally in minutes, even as peace talks are in question
By Eva RoytburgMarch 23, 2026
2 days ago
HealthHealth
Forest ‘bathing’ can reduce stress, improve mood, lower blood pressure and boost the immune system. Here’s how it’s done
By Allen Breed and The Associated PressMarch 22, 2026
3 days ago

Most Popular

Magazine
The youngest-ever female CEO of a Fortune 500 company is fighting Trump's cuts to keep Medicaid strong
By Fortune EditorsMarch 24, 2026
2 days ago
Commentary
The Treasury just declared the U.S. insolvent. The media missed it
By Fortune EditorsMarch 23, 2026
2 days ago
Success
Palantir’s billionaire CEO says only two kinds of people will succeed in the AI era: trade workers — ‘or you’re neurodivergent’
By Fortune EditorsMarch 24, 2026
1 day ago
Success
The job market is so bad that ‘reverse recruiters’ are charging $1,500 a month just to help people look for jobs
By Fortune EditorsMarch 25, 2026
19 hours ago
Success
JPMorgan’s Jamie Dimon says remote work breeds ‘rope-a-dope politics’ and stunts young workers’ growth
By Fortune EditorsMarch 25, 2026
11 hours ago
Success
JPMorgan has started monitoring the keystrokes, video calls, and meetings of its junior investment bankers—and they say it's for employee well-being
By Fortune EditorsMarch 24, 2026
1 day ago