Whooping cough is spreading fast across Michigan.

The state had 330 reported cases of pertussis, or whooping cough, by mid-August. That’s three times the total for all of 2023, according to Bridge Michigan.

The Michigan Department of Health and Human Services says it’s a return to pre-pandemic levels. Protection for the vaccinated can decrease over time, and the highly contagious infection can be deadly for infants.

Whooping cough is best known by a violent cough and the inability to catch your breath. Health officials fear that the start of Michigan’s school year will only cause the numbers to skyrocket even further.