The arm you choose when you get a shot matters more than you might think.
A new study, highlighted by CBS News, shows that where you get a shot could impact how a vaccine performs, and make a difference in how your body mounts an immune response.
The Garvan Institute of Medical Research, based in Australia found that a booster vaccine in the same arm as your first dose can create conditions for a quicker immune response.
“This is a fundamental discovery in how the immune system organizes itself to respond better to external threats – nature has come up with this brilliant system," Professor Tri Phan, the Director of the Precision Immunology program, said.
Vaccines have made headlines for months, as rates appear to be waning among the U.S. population.
The US has topped 1,000 measles cases and 2025, according to data from the CDC and some state health departments.
Governor Josh Green (D), Hawaii, is also a physician and highlighted the issue with measles and vaccination rates.
“The problem is, when vaccination rates fall below 95 percent for measles, or under 90 percent in public schools, you see big outbreaks,” he said.
We recently sat down with Dr. Nicole Saint Clair, Executive Medical Director of Regence BlueShield, about the prevalence of measles, and she emphasized that the MMR vaccine is safe and effective.
“Vaccination with the MMR gives you almost 100 percent protection. Some vaccines you might need a booster, some you don’t,” Dr. Saint Clair said. “For measles, we don’t necessarily talk about boosters for adults once they’ve completed the series, but there are sometimes when you may need a different booster.”
Medical professionals want more people to get shots to stem the tide of some diseases that are reappearing.
So next time you get a booster, think twice about which arm you choose. Getting it in the same arm where you received your original dose could deliver you faster protection.
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