Nearly half of this year's cases were among people who had never received a dose of whooping cough vaccines, Oregon officials said.

Oregon is expected to beat the state’s record for whooping cough, also known as pertussis, cases by the end of the year, as Clark County recently reported the highest number of cases among all Washington state counties.

Oregon health officials are alarmed over the state's rising pertussis case count, which is expected to beat the state's record, Oregon Health Authority announced Thursday.