seems absolutely true. thank you so much. great work in st. petersburg. back here at home a growing health alert. several states are seeing an alarming increase in cases of choopg. in tex what's causing whooping cough and what can be done about it? elizabeth cohen is at the cnn center in atlanta with more. good morning, elizabeth. >> reporter: good morning, kate. kate, you have a really bad combination going on right now. you have kids going back to school so once again they're in close quarters and you have a vaccine that fades over time. the awful sound of whooping cough. a brutal cough that can last for months. a potentially fatal illness for babies and young children who haven't had a chance to get all their shots yet. >> they may have spells of apnea where they stop breathing.