Recently heard Joe Rogen adjacent podcasters discussing COVID-19 vaccines and their effectiveness and safety? Wondering whether that guy at the bar who keeps insisting that COVID shots are nonsense might have a point? So, is it worth getting a COVID-19 booster in 2026 and onwards?
If you are looking for evidence-based information about the efficacy of the current COVID-19 boosters, we are here for you. This week a team of scientists, led by experts from the USA’s Centers for Disease Control and Prevention, gave an update on how well the 2024–2025 COVID-19 vaccines have been working in JAMA Internal Medicine.
COVID-19 Boosters – Who needs ’em?
It’s six years since SARS-Cov2-19 swept across the globe, and it has now joined the endemic disease gang along with chicken pox, the common cold and flu. While it might be a background concern for most of us, it can still hit hard. Infectious disease experts recommend that people with chronic lung disease, heart conditions, diabetes, asthma and obesity as well as older adults, pregnant women and folk with compromised immune systems should stay up to date with their COVID-19 shots. What about the rest of us? Should you bother getting a COVID-19 booster in 2026/2027?
Is there evidence that COVID-19 boosters work for them and for the average Joe? The answer is yes. According to epidemiologists even people with a well-functioning immune system benefit from getting a COVID shot. They report that a booster can cut your chances of being admitted to hospital with COVID-19 complications by 35% within 10 months of your shot.
Don’t take my word for it, though! Let’s take a look at the evidence.
Data Detectives
The CDC collects data from hospitals about respiratory viruses circulating in the population. Hospitals in Colorado, Minnesota, Wisconsin, Utah, California, Indiana, Oregon and Washington, USA share data with the CDC through the electronic health record system.
Biostatisticians and other researchers have access to anonymized data about how many people turn up with a respiratory infection, how bad it is, general demographic information and vaccine status. This helps the CDC to spot an epidemic quickly and to identify at risk groups while keeping track of vaccine efficacy.
In this study the team focused on nonimmunocompromised patients who had had a single 2024/5 COVID-19 booster between six and 299 days ago if they were under 65, and two boosters if they were 65 years old and over. That means adults with a healthy immune system.
Only folk with a positive COVID-19 test would count as a COVID case. The researchers would treat everybody else who came to the hospital with COVID-like symptoms as controls.
The analysis would exclude COVID-19 positive patients who also tested positive for flu or RSV. This is because the researchers would not be able to determine whether they were very sick due to COVID-19 or because of the other virus.
Who Came to the Hospital?
Between September 2024 and September 2025, emergency department doctors saw 333, 262 people aged over 18 years who had a COVID-19-like illness. Of those, 21,152 tested positive for the virus. Overall, roughly one in five had had a 2024/5 COVID booster but only 15% of people who tested positive for COVID-19 had up-to-date shots. Most people who were boosted got a 2024/5 Moderna shot, followed by Novavax with Pfizer coming last.
Score 1 for the boosters. If you didn’t have a booster, you were more likely to get COVID-19 bad enough for an ER visit.
The average patient turning up to the ER with COVID-like symptoms was on the older side, 63% were 18–64 and 37% were 65 and over. Half of them were aged 54 years plus. Women were more likely to visit than men (60%) and more than half (61%) self-identified as white, non-Hispanic.
While 63% of visits were for people under 65, only 59% of them tested positive for COVID. People who identified as White were over-represented in the virus – positive cases at 66%. People who identified as African American or Black were less likely to be COVID positive at 8% of cases and 11% of visits. For some reason the authors don’t include Asian Americans, Pacific Islanders or Native American/Indigenous people as their own category. Usually folk with Middle Eastern and North African heritage are classified as White but the authors don’t specify in this study.
Fewer COVID Boosted People Positive
So, only 15% of people testing positive for COVID had been boosted. What does that actually mean? The statisticians used the figures to calculate the odds of a person who had had their booster having to visit the ER room because of COVID. They found that if you got your 2024/5 COVID-19 booster, you lowered your chances of being sick enough to go to the ER by around 26%. If you had been vaxxed more than 6 months before, it was a little less effective, only reducing the odds by 11%.
Getting a COVID booster lowered everybody’s chances of getting sick enough with COVID-19 that they had to visit the emergency department. The youngest person who checked in with COVID was 35 years old.
These boosters don’t just help seniors. More than 12,000 people under 65 had a case of COVID-19 so bad that they had to go to the emergency department. Only 866 (around 7%) of them had got a shot in the last 299 days.
Boosters Prevented Hospitalizations
COVID boosters didn’t just help to reduce ER visits. They also prevented hospital admissions. During the study period, 97, 663 patients were so sick with a COVID-like illness that they were admitted to hospital for treatment and observation. Half of those patients were aged between 72 and 81, with the youngest being 59. Twenty-four per cent of all the patients admitted had got a 2024/5 COVID-19 booster, but only 19% of genuine COVID cases were vaccinated.
Score 2 for 2024/5 COVID boosters. COVID positive patients who had not got their booster were over-represented amongst patients who were hospitalized.
Calculating the vaccine efficacy, the team say that folk who had got their booster in the six months before getting sick were 35% less likely to need a hospital stay than people who did not get their booster. The most gains were seen in older patients; only 1179 patients between 59 and 64 were admitted with a positive COVID-19 test, versus 4039 at 65 years and over.
If you were over 50, getting a COVID booster with the last 10 months or so reduced your odds of being hospitalized by over a third, rising to 50% if it was in the past 60 days. Still wondering if it’s worth getting a COVID-19 booster?
Avoid Critical Illness with a COVID-19 booster
Of 70,695 patients who were classed as critically ill, only 976 tested positive for COVID-19 and 151 of them had been vaccinated. Only eighteen of the 237 patients under 65 who tested positive for the virus had been boosted. In the senior category, 720 patients were very poorly and 133 had been boosted.
The researchers put the benefit of being vaccinated at 40% improvement in your chances of your COVID-19 infection not making you critically ill.
Score 3 for COVID boosters.
So overall, getting boosted gave adults with an average immune system better odds of avoiding being sick enough to visit the ER, being sick enough to be hospitalized and becoming critically ill.
Does this really apply to you and me?
While these reductions in risk are pretty good, we should also acknowledge its limitations. We are in the real world, so this study is, of course, not perfect.
For a start, the numbers in some categories are very small. This makes extrapolating the conclusions to cover the whole population less reliable than you would want. However, these small numbers work in favour of a big picture conclusion that the vaccines are helping; people who were boosted were less likely to get sick in the first place.
Another issue is that the categories are pretty vague. What is a COVID-like illness? What does critical illness mean? There was not much data on the relative seriousness of ER visits. Are people who get boosted more or less likely to go to hospital with respiratory illness due to psychological factors?
Is It Worth Getting a COVID-19 Booster in 2026?
Finally we have to acknowledge the elephant in the room. This study is a snapshot of how people sick people get if they are nonimmunocompromised. They might not be in perfect health to begin with. In fact, many of the people admitted to hospital had at least one underlying illness, sometimes as many as three. Is this really representative of the average American who is not immunocompromised? Is it really worth getting a COVID-19 booster?
The answer is yes. Cardiometabolic and cardiovascular disease are the biggest risk factor when it comes to how sick COVID-19 will make you. The three biggest risk factors are obesity, diabetes and hypertension.
While everybody imagines themselves as pretty healthy, let’s take a quick look at the stats. The CDC estimates that, as of 2023, 40 million people in the USA have some form of diabetes. That’s 12% of the population. A scary 115.2 million adults, according to estimates, have prediabetes. That’s nearly a third of Americans.
More than four in ten Americans over aged 20 are classed as obese based on BMI or anthropometric measures.
A staggering 48% of US adults had blood pressure high enough for a hypertension diagnosis in 2023, that’s 119 million. In 2024 680,179 people died as a result of the condition.
Now you have the information, the rest is up to you.
Sources
Wiegand RE, Payne AB, Mak J, et al. Estimated Effectiveness of 2024-2025 COVID-19 Vaccines in Adults. JAMA Intern Med. Published online June 15, 2026. doi:10.1001/jamainternmed.2026.1936
CDC. National Diabetes Statistics Report. Diabetes. January 21, 2026. Accessed June 15, 2026. https://www.cdc.gov/diabetes/php/data-research/index.html
Reddy KR, Faridi KF, Aggarwal M, et al. Proposed Mechanisms and Associations of COVID-19 with Cardiometabolic Risk Factors. Am J Lifestyle Med. 2026;20(1):4–13. doi:10.1177/15598276241269532
O’Hearn M, Liu J, Cudhea F, Micha R, Mozaffarian D. Coronavirus Disease 2019 Hospitalizations Attributable to Cardiometabolic Conditions in the United States: A Comparative Risk Assessment Analysis. J Am Heart Assoc. 2021;10(5):e019259. doi:10.1161/JAHA.120.019259
CDC. High Blood Pressure Facts. High Blood Pressure. June 3, 2026. Accessed June 15, 2026. https://www.cdc.gov/high-blood-pressure/data-research/facts-stats/index.html
CDC. People with Certain Medical Conditions and COVID-19 Risk Factors. COVID. November 17, 2025. Accessed June 15, 2026. https://www.cdc.gov/covid/risk-factors/index.html
FastStats. March 6, 2026. Accessed June 15, 2026. https://www.cdc.gov/nchs/fastats/obesity-overweight.htm
