More than 25,000 cases of whooping cough (pertussis) have been recorded in the U.S. so far this year, according to updated CDC data.
This is the second consecutive year with higher-than-usual cases; around 33,000 cases were reported at this same time last year.
The big picture: Current case counts are well above pre-pandemic levels, compared to about 18,600 cases in 2019.
- The last time cases reached similar levels was in 2014, with more than 32,900 cases recorded.
- Doctor visits for pertussis peaked in the winter of last year but remain elevated compared to prior years, according to Epic Research.
Why it matters: Whooping cough is a highly contagious respiratory illness caused by Bordetella pertussis bacteria, which damage the upper airway cilia and cause swelling.
- The illness is especially dangerous for babies and young children; several deaths have been recorded this year, including in Louisiana and Washington state.
Go deeper: Transmission occurs through coughing and sneezing, and infected individuals may be contagious for weeks before diagnosis.
- Early symptoms resemble a common cold, including runny nose, cough, and low-grade fever, but can escalate to violent coughing fits lasting up to 12 weeks.
- Antibiotics can treat whooping cough and early treatment helps reduce infection severity; most symptoms can be managed at home.
- Introduction of the whooping cough vaccine in the late 1940s led to a dramatic decrease in cases – over 90% lower than before vaccination.
- Before vaccines, about 200,000 cases occurred annually among children, with up to 9,000 annual deaths.
- Two vaccine types are used: DTaP for children under 7, and Tdap for older children, adults, and pregnant women.
- Vaccination rates against whooping cough have dropped recently; only 92.1% of kindergarteners were vaccinated during the 2024-25 school year, compared to about 95% pre-pandemic (2019-2020).
