(CNN) In the United States, the culprit behind most rabies cases has shifted from dogs to bats. The flying mammals now cause 7 out of 10 US rabies cases, according to a report from the Centers for Disease Control and Prevention.

Researchers looked at rabies trends in the United States over the span of 80 years, from 1938 to 2018. They found that most infections came from dog bites until 1960, when wildlife species -- specifically bats -- became the primary source for human infection. This followed nationwide efforts in the 1950s to mandate pet vaccines and implement leash control laws, the report stated.

"Reducing rabies in dogs is a remarkable achievement of the U.S. public health system, but with this deadly disease still present in thousands of wild animals, it's important that Americans are aware of the risk," CDC Director Dr. Robert Redfield said in a news release.

From 1960 to 2018, 125 human rabies were cases reported in the United States. Of these, 28% came from contact with dogs outside the United States, where rabies vaccines may not be required or readily available. The cases acquired in the United States came from wildlife species, with 70% resulting from bat bites or scratches and the rest due to human contact with raccoons, skunks or foxes.

Once a person becomes infected, rabies is nearly always fatal without treatment. The number of deaths in the United States ranged from 30 to 50 per year in the 1940s but has since dropped to one to three deaths per year. That's the result of routine pet vaccination and availability of post-exposure treatment with vaccine and immune globulins, proteins that trigger the body's defense system to fight off infection.

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