About a quarter of Iowa’s counties are seeing cases of what’s often thought to be a child’s disease — which can be fatal. Many adults are also being struck by pertussis or whooping cough. Cerro Gordo County Health Department spokeswoman Teresa Symens (SIM-ons) says adults need to be warned they CAN get the disease, even if they got a shot for it years ago.Symens says adults who’ve caught whooping cough may think they’ve just got a nasty cold — but it can get much worse and even can be deadly without proper treatment.Cerro Gordo County is seeing many more cases of the disease, given the time of year and the warm weather. She says the infection is one that’s easily transmitted from one person to another.There’s been -one- confirmed death in Iowa from whooping cough in recent months and cases are reported in at least 25 counties.