Most of us considered whooping cough a rare disease affecting small children but it's no longer rare and it's more common among adults than children.
California's health department Thursday announced cases of whooping cough doubled in the first quarter of the year.
Some counties in the midwest report a 10-fold increase.
Doctor William Cochran of Geisinger Medical Center near Danville fears his own ordeal proves it could happen in Pennsylvania.
After examining several children last fall, Dr. Cochran headed to Alabama to help his son fix up an old house. The doctor soon got sick.
"I would just go ahead and start coughing. Just cough and cough and cough and cough and cough and cough and cough and cough and cough" Cochran said.
So much coughing Dr. Cochran could not help his son. He left Alabama and headed home to Danville, wondering what was wrong with him.
"This was the worst disease I've ever had in my life," Dr. Cochran added.
He returned to Geisinger as a patient, too sick to work. After treatment he received a shocking diagnosis.
Cochran and other doctors thought his asthma was worsening, then they heard the sound of his cough.
"You would hear a little whoop which is part of the reason they call it whooping cough," the doctor explained.
Whooping cough is the clinical name for pertussis.
What was once primarily a childhood disease nearly wiped out by vaccines is now making an insidious comeback.
Doctor Cochran couldn't believe he had whooping cough. He was vaccinated against it a child in the 1950s.
But throughout his 30 year medical career the doctor, like 80 percent of Americans over 25, did not get revaccinated as an adult.
What does it say when a doctor doesn't know? "I think that shows how much education we really need to do for the general. I think it is a very serious public health concern," said Cochran. Serious because more parents now refuse to vaccinate their children.
They fear preservatives in vaccines cause autism, a fear Cochran said could lead to the spread of whooping cough.
"If you take that unvaccinated child, who then develops one of those illnesses, and they go see grandma and grandpa, who have not been re-vaccinated, that illness can be extremely severe in that elderly person," explained Cochran.
Pertussis is also known as the 100 day cough and that's how long it took Dr. Cochran to fully regain his health.
He's now helping a Pennsylvania Department of Health campaign urging adults to get booster shots for pertussis and other illnesses.