U.S. health officials say whooping cough is at its highest level in a decade for this time of year. The Centers for Disease Control and Prevention said Thursday that so far this year there have been about 18,

Only four years since 1958 have seen a higher number of whooping cough cases, according to the Washington state Department of Health.

There have been 18,506 cases of whooping cough reported so far, the Centers for Disease Control and Prevention said. That’s the most at this point in the year since 2014, when cases topped

Whooping cough is at its highest level in a decade for this time of year, U.S. health officials reported Thursday.