The United States is experiencing a significant resurgence in whooping cough, or pertussis, with over 32,000 cases reported this year—the highest count in a decade, Gizmodo reports.
According to the Centers for Disease Control and Prevention (CDC), the number of pertussis cases in 2024 has increased fivefold compared to 2023, which recorded only about 6,500 cases. Experts attribute this alarming rise to a combination of factors, including declining vaccination rates and changes in vaccine formulations.
Pertussis, caused by the bacterium Bordetella pertussis, is characterized by severe coughing fits that often result in a “whooping” sound when patients struggle to breathe. While the infection is typically mild in adults, it can be severe or even life-threatening for young children and individuals with weakened immune systems.
The pertussis vaccine has been a cornerstone of public health since its widespread introduction in the late 1940s as part of the combined DTaP vaccine, which also protects against tetanus and diphtheria. Before vaccination programs, annual pertussis cases in the U.S. ranged between 100,000 and 300,000. The vaccine dramatically reduced the disease’s prevalence, though tens of thousands of cases still occurred annually in the 2000s.
During the COVID-19 pandemic, social distancing measures indirectly reduced the spread of pertussis and other infectious diseases. However, with the easing of restrictions and the resumption of normal social activities, pertussis cases have climbed back to pre-pandemic levels.
This year’s case count is particularly concerning, as it surpasses any year since 2014, when 32,971 cases were reported. In some states, the surge has been linked to declining vaccination rates among residents and their children.
The modern pertussis vaccine, used in the US and many other countries, differs from the original whole-cell vaccine. Although safer, the newer acellular vaccine provides less robust and shorter-lived immunity. This trade-off has made periodic outbreaks more likely, especially in populations with incomplete vaccination coverage.
Vaccination remains the most effective method to prevent pertussis outbreaks. However, current data reveal gaps in immunization. Approximately 80% of US children under two have received the recommended DTaP series, and 90% of teenagers have received at least one dose of the Tdap vaccine. Among adults, only 43% have received a Tdap booster within the last decade, though these boosters are crucial to maintaining immunity.
Pertussis remains a significant global health issue, particularly in countries with low vaccination coverage. Worldwide, the disease causes an estimated 24 million cases annually, resulting in 161,000 deaths in children under five.
