A New Kind of Flu Shot! The Same Technology Behind COVID Vaccines Just Got a Flu Upgrade
Quick Summary
The United States government has approved a brand-new type of flu vaccine. It is called mFlusiva, made by a company called Moderna. It uses the same mRNA technology that made COVID-19 vaccines so fast and effective. Scientists say it works even better than many traditional flu shots.
What Happened?
Every year, the flu — short for influenza — makes millions of people sick. People get coughs, fevers, sore throats, and aching muscles. Flu shots help protect people by teaching the body’s immune system what the flu virus looks like, so it is ready to fight it off.
For decades, flu vaccines have been made the same old way — using weakened viruses grown inside eggs. It works, but the process is slow. Creating a new vaccine can take months.
mRNA technology works differently. Instead of using any actual virus, it delivers a tiny set of instructions — called messenger RNA — into your cells. Think of it like a recipe card. The recipe tells your cells to make a small harmless protein that looks like part of the flu virus. Your immune system sees that protein, does not like it, and learns to fight it. Then, if the real flu virus shows up later, your body is ready.
On August 5, the U.S. Food and Drug Administration approved mFlusiva for adults aged 50 and older. It became the first flu vaccine ever made with mRNA technology. Moderna tested it on more than 40,000 people. In those trials, mFlusiva worked about 27% better than standard flu shots at preventing illness.
Moderna says the vaccine should be available at pharmacies this fall, ahead of the 2026–2027 flu season.
Why Does It Matter?
mRNA vaccines can be updated quickly. If a new and dangerous version of the flu virus appears — which scientists call a pandemic strain — scientists could redesign an mRNA vaccine in days or weeks, not months. That could save many lives in an emergency.
This is the same technology that helped the world respond to COVID-19 so fast. Now it is being used for one of the most common illnesses people face every year.
For now, the vaccine is approved only for adults 50 and older. Scientists are continuing research to see if it can help younger people too.
Big Words
- mRNA (messenger RNA) — a tiny molecule that carries instructions from your DNA to your cells, telling them what proteins to build; vaccine makers can now use it to teach immune systems to fight diseases.
- Immune system — the body’s defense system — a network of cells and proteins that recognizes and fights off germs.
- Influenza — the scientific name for the flu, a contagious disease caused by influenza viruses that infect the nose, throat, and lungs.
- FDA (Food and Drug Administration) — the U.S. government agency that checks whether new medicines and vaccines are safe and effective before they are used by the public.
- Pandemic — when a disease spreads very quickly and widely around the whole world at the same time.
Fun Fact
mRNA is used inside every living cell on Earth every single day! It is the molecule your body naturally uses to build proteins. Scientists just learned how to write their own mRNA messages and turn your cells into tiny vaccine factories.
Think About It
mRNA vaccines can be designed and updated much faster than old-style vaccines. Why might that speed be especially important if a brand-new, dangerous flu virus appeared tomorrow?
Sources
- CNN — FDA approves first mRNA-based flu vaccine
- NPR — FDA approves Moderna flu shot made with mRNA
- NBC News — FDA approves 1st mRNA flu shot, from Moderna
- STAT News — FDA approves Moderna’s mRNA flu vaccine, the first to use the technology
- Healthcare Dive — FDA approves Moderna’s mRNA flu vaccine