• U.S. whooping cough cases have increased dramatically to over 32,000 as of December 2024, approximately six times higher than the previous year and the highest level since 2014.
• The Midwest region accounts for about 25% of all reported cases, with Pennsylvania recording the highest state numbers, while Oregon has reached its highest case count since 1950.
• Public health officials attribute the surge to declining vaccination rates, with only 92% of kindergartners receiving the DTaP vaccine for the 2023-2024 school year, and the return to pre-pandemic transmission patterns.