This bar chart shows the year-to-date count of whooping cough cases since 2010, current through the first 50 weeks of each year. In 2010 there were 23,000 cases, then in 2012 more than 46,000 (the most of any shown year), and after that case numbers declined, to 18,000 in 2015, 5,800 in 2020 and bottomed out at 2,100 in 2021. In 2024 more than 32,000 have been reported.