CNN —When you go to get your newly updated Covid-19 booster this fall, you might want to choose the arm the vaccine goes in carefully. The immune response may be stronger if your booster goes in the same arm as your last Covid-19 shot, according to a study published August 11 in the journal eBioMedicine. The immune response may be stronger if a Covid-19 booster goes in the same arm as your last shot, a new study suggests. Two weeks after the booster, the number of “killer T cells” was significantly higher in those who had both shots in the same arm, according to the study. This study made Schaffner think about this fall, when he will get vaccines for respiratory syncytial virus, known as RSV, and influenza as well as a Covid-19 booster.

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Persons: Martina Sester, Scott Olson, Laura Ziegler, “, ”, William Schaffner, Schaffner Organizations: CNN, of Infection, Saarland University Hospital, Saarland University, Vanderbilt University Medical Center, National Foundation for Infectious Diseases, American Cancer Society, National Institutes of Health Locations: Germany, Nashville