The harrowing, deadly infection could make a comeback, especially in states vulnerable to climate-linked natural disasters, like Florida and Texas, an NBC News investigation finds.

After decades of success against tetanus in the U.S., there are troubling signs that the deadly bacterial infection could make a comeback, a fallout from the drop in vaccination combined with a rise in climate change-related natural disasters that can increase the risk of exposure.

In 1948, when the tetanus vaccine was first combined with diphtheria and pertussis, 601 cases of tetanus were reported in the U.S. In recent years, that has dropped to about 15 to 28 annual cases.

In 2024, however, there were 32 cases. This year, there have been at least 37 confirmed cases, the most in over a decade.

An NBC News/Stanford University investigation has found widespread declines in kindergarten vaccination against tetanus. In states that provided data back to 2019, more than 75% of counties and jurisdictions across the U.S. have seen downward trends in young children getting the diphtheria-tetanus-pertussis (DTaP) series of shots. The vaccine is first given to babies at 2 months.