Measles vaccination rates may be lower than thought, undermining herd immunity concept

Measles vaccination rates for young children may be far lower than publicly reported, a troubling development that could mean the United States is closer than expected to losing its “elimination status” for the extremely contagious disease.

“We are experiencing an extremely concerning decline in measles vaccination in the very group most vulnerable to the disease,” said Benjamin Rader, a computational epidemiologist at Boston Children’s Hospital, an assistant professor at Harvard Medical School and the author of a recent study that looked at children’s vaccination rates.  

As of Wednesday, there have been over 420 cases of measles this year – already surpassing the total number of cases for 2024. Most are in West Texas, where a growing outbreak has spread into neighboring states, but a handful of cases, linked to international travel, have been reported in other states. The cases have mostly been in unvaccinated people or those with an unknown vaccination status, according to the Centers for Disease Control and Prevention.

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