When you've heard it before, you recognize it immediately.
"The cough is very characteristic and often the old grandmoms are the only ones who remember it, but once you hear it you remember it," according to Dr. Lawrence Ross, Children's Hospital L.A. Infectious Disease.
Whooping Cough is a highly contagious disease. A typical case starts with a cough and runny nose for one to two weeks, followed by weeks or months of rapid coughing fits that sometimes end with a whooping sound.
"Not everyone will whoop, and what we characterize after the cough is that after this bad cough episode individuals will vomit or turn blue or red in the face and young infants may just stop breathing entirely," according to Dr. Lawrence Ross, CHLA Infectious Disease.
That's why Whooping Cough is so dangerous for very young children. They can't get immunized against it until they're six weeks old, and it's going around.
Five babies have died in the state already this year.
State officials say this could be the worst year for Whooping Cough in half a century.
Immunization is the best defense, although since Whooping Cough is caused by a germ, not a virus, immunization is not a one shot deal.
"The problem is the vaccine’s effectiveness wears off after five to eight years, and you become susceptible to it. But the same thing happens even if you have the disease. If you had whooping cough as a child, years later you're at risk of getting Whooping Cough again," according to Dr. Lawrence Ross, CHLA Infectious Disease.