According to new study data, roughly three in four kids had a cough one week after being treated in the emergency department, and one in four had a chronic cough after 28 days.

“In most children in the study, the cause of the chronic cough was an underlying lung infection that is easily treated with antibiotics, a condition called protracted bacterial bronchitis,” senior study author Dr Anne Chang told Reuters by email. “However, most children with cough do not need antibiotics.”

Among the 171 children who still had a cough at the end of the study, 59 (35%) had a wet cough, while 45 (26%) had a dry cough, researchers report in the Archives of Disease in Childhood. (In the rest, the cough was either variable, or the data were missing.)