While comparing studies that looked at different results is difficult, the college students in the study appear to have fared better than the toddlers in a recent one that looked at some of the same seasons. In that study, vaccination did not appear to reduce hospital visits.
But that is to be expected.
"It's not inconsistent that these young vigorous adults who have vigorous immune systems might be better protected than those young children," Vanderbilt's Schaffner said.
He noted that the college students are more likely to have been exposed to the virus, meaning their immune systems are more primed.
While the University of Minnesota has its vaccine covered under the student health plan and St. Olaf College charges a small fee, researchers declined to make a comparison between the two institutions.
But Minnesota's Ehlinger said that a free vaccine certainly made it easier to get more students immunized.
If students had to pay, "we wouldn't be getting the same numbers we're getting," he said.
Study researchers believe that increased vaccine use will benefit college students in other ways.
"If we want to get to universal coverage with immunization, a good place to do that is with college students," Ehlinger said, adding that vaccination in college would give them the habit of being vaccinated later in life.
Ehlinger also noted that students at state schools like Minnesota have half their tuition paid for by the state's citizens, and getting them immunized would keep them in the classes that taxpayers were covering.
"Keeping students in class is a good investment that all of us have in college students," he said.