There are 71 new cases in the ongoing outbreak of H3N2v swine flu, bringing the U.S. total to 224 cases since July 2012.

Ohio had 41 new cases, bringing its total to 72. Indiana had 18 new cases for a total of 138. Michigan, Wisconsin, Pennsylvania, and West Virginia saw their first cases. Illinois, where there had been one previous case, reported two new cases.

Every case investigated so far has involved contact with pigs. Although there were a few cases of limited person-to-person spread last year, that hasn't yet happened this year.

"A key thing we are looking for is whether the virus is spreading from person to person," CDC flu expert Joseph Bresee, MD, said in a news release. "That kind of change would affect our risk assessment. So far, we are not seeing that and we are looking carefully."

Confirming that the new flu bug isn't spreading is data from the national flu surveillance system. The system hasn't detected any unusual overall spike in the number of flu cases.

There's more good news: The new swine flu isn't any more deadly than regular seasonal flu. There haven't been any deaths, and only a few hospitalizations. Everyone infected this year has fully recovered.

But it's not over yet. CDC and state flu experts are on alert.

"We expect the number of H3N2v cases to rise since this virus has been found in pigs in a number of U.S. states ... and there is so much interaction between people and pigs in fair settings at this time of year," Bresee said.