Key points
- CDC tracks pertussis cases using a national surveillance system.
- CDC works with several states on enhanced pertussis surveillance.
- Cases have increased over the last few decades.
- Experts believe that much of the disease goes unrecognized and unreported.
- Learn where pertussis data come from and latest trends.
Recent trends
Preliminary data show that fewer cases of pertussis have been reported in 2026 compared to the same time in 2025. Reported pertussis cases last peaked in November 2024. Pertussis is a cyclical disease, which means after a peak in reported cases, a decrease is expected. CDC will continue to monitor reports of pertussis. Learn more about trends in pertussis over the years.
Data reporting
Surveillance reports and weekly data
View pertussis data, including case counts and incidence by state and age, DTaP vaccination history of cases, and counts of pertussis-related deaths.
- 2025 provisional report
- 2024 provisional report
- 2023 final report
- 2022 final report
- 2021 final report
These and older surveillance reports can be found at CDC Stacks.
Since pertussis is a nationally notifiable disease, you can view weekly data. Those data are available on infectious disease table tables from NNDSS.
Explore the data
Use the figure below to see reported U.S. pertussis case counts from NNDSS since 1922. To zoom in on a select range of years, slide the bar beneath the figure. The case counts for years highlighted in the grey vertical bar are provisional. You can also view the data in table format by clicking on "Data Table" beneath the figure.
Infants experience the highest incidence
Infants under one year old are at greatest risk for serious disease and death because their immune systems are still developing. This age group continues to have the highest reported rate of pertussis.
Use the figure below to see reported U.S. pertussis incidence per age group since 1990, sourced with NNDSS data. Incidence highlighted with the grey vertical bar is provisional. Hover over the lines in the figure to interact with the data. You can also view the data in table format by clicking on "Data Table" beneath the figure.
Data systems
National Notifiable Diseases Surveillance System
Pertussis is a nationally notifiable disease. See the pertussis case definition.
Healthcare providers should notify the appropriate health department of all patients with suspected pertussis.
Diagnostic laboratories should notify health departments of all positive pertussis laboratory results.
State health departments then report pertussis cases to CDC through the National Notifiable Diseases Surveillance System (NNDSS). NNDSS is useful for monitoring epidemiologic trends in disease over time.
Enhanced Pertussis Surveillance
CDC partners with seven states participating in the Emerging Infections Program network to conduct Enhanced Pertussis Surveillance. This network also conducts surveillance on other Bordetella species.
EPS sites
- Conduct enhanced case ascertainment and augmented data collection.
- Collect isolates and specimens for further characterization at CDC.
- Provide infrastructure for conducting pertussis special studies.
This additional information goes beyond what CDC receives through NNDSS.
Historical trends
Before widespread vaccination
In the 20th century, pertussis was one of the most common childhood diseases and a major cause of U.S. childhood mortality. Before the availability of a pertussis vaccine in the 1940s, public health experts reported more than 200,000 cases of pertussis annually.
1940s to mid-1980s
Widespread use of the vaccine in children began with the introduction of the diphtheria, tetanus toxoid, and whole-cell pertussis (DTP) vaccine in 1948. Since then, the number of cases each year has decreased more than 90%, compared with the pre-vaccine era.
Late 1980s to 2010s
During the 1980s, pertussis reports began increasing gradually, leading to a peak in 2012 with 48,277 reported cases.
Several factors likely contributed to the increase in reported cases, including
- Improved recognition of pertussis by healthcare providers
- Greater access to and use of laboratory diagnostics
- Increased surveillance and reporting to public health departments
- Waning immunity from acellular pertussis vaccines
Since 2012, reported cases remained elevated until the start of the COVID-19 pandemic in 2020.
2020s
Reports of pertussis cases were lower than usual during and immediately following the COVID-19 pandemic. It's likely mitigation measures used during the pandemic (e.g., masking, physical distancing) lowered transmission of pertussis.
In 2024, the United States returned to pre-pandemic patterns where more than 10,000 cases are typically reported each year. Preliminary data show that more than six times as many cases were reported in 2024 compared to 2023. The number of reported cases in 2024 was higher than what was seen in 2019, prior to the pandemic.
In 2025, preliminary case report numbers remained elevated compared to immediately before the pandemic. However, reported cases of pertussis trended down since a peak in November 2024. Case counts will likely change as CDC finalizes the data.
Case definition
The Council of State and Territorial Epidemiologists (CSTE) published the most recent case definition for pertussis in 2020.
Antibiotic resistance
To date, reports of antibiotic-resistant B. pertussis have been rare in the United States. However, resistance to macrolides, a class of antibiotics commonly used to treat pertussis, has been increasingly reported in other regions globally. Regions reporting this increase include Asia, Australia, Europe, and South America.
CDC closely monitors B. pertussis antibiotic resistance in the United States by testing isolates from CDC's Enhanced Pertussis Surveillance.