Overview

• The U.S. has reported 14,569 whooping cough cases this year, a fivefold increase from the same period last year.
• Ontario is on track to exceed its highest case count since 2012, with 1,016 cases reported as of September 9.
• Quebec has seen a decline in weekly cases but remains the hardest-hit province in Canada with 13,716 cases this year.
• Experts attribute the rise in cases to the waning efficacy of current vaccines and potential bacterial mutations.
• Human challenge trials are being considered to speed up the development of more effective and longer-lasting vaccines.