Whooping Cough Cases Surge to Decade-High Levels in the U.S.
Whooping cough, also known as pertussis, is making an unwelcome resurgence, with cases in the U.S. reaching a ten-year high. As of Dec 14, nearly 32,085 cases have been reported to the Centers for Disease Control and Prevention (CDC), a fivefold increase from the roughly 6,500 cases recorded in 2021. Experts attribute the surge to various factors, including vaccination rates.
Pertussis is caused by the Bordetella pertussis bacterium, which typically causes respiratory symptoms, including violent coughs that have earned it its "whooping" moniker. While the infection is usually mild in adults, it can be severe in young children and vulnerable populations, such as those with weakened immune systems.
The first pertussis vaccine was invented over a century ago, but it wasn’t until the late 1940s that it became widely recommended and used in combination with vaccines for tetanus and diphtheria. Since then, this combined injection has been a mainstay of U.S. vaccination programs, significantly reducing whooping cough cases. Before mass vaccination, there were between 100,000 and 300,000 cases reported annually in the U.S.
Since 2000, the U.S. has reported tens of thousands of pertussis cases each year. However, the COVID-19 pandemic indirectly reduced disease spread due to social distancing practices, leading to a decrease in pertussis cases. Now, as the world returns to pre-pandemic social habits, pertussis cases are rising again. CDC data indicates that the increase is partly due to a return to more typical trends.
However, this year’s case count is unusually high for modern times, being the highest since 2014 when there were 32,971 cases. In some states, experts and health officials have blamed waning vaccination rates among residents and their children for the increase.
Another crucial factor is the nature of the vaccine itself. The U.S. and many other countries switched to a newer, acellular pertussis vaccine in the 1990s after global concerns about the safety of the whole-cell version. While the new vaccine is safer, evidence shows it offers less immediate and lasting protection against pertussis. Experts argue that future pertussis outbreaks are likely to be larger under the current vaccine regime.
Despite these challenges, vaccination remains the most crucial tool to keep whooping cough in check. Low vaccination rates increase sustained outbreak risk. Globally, pertussis causes 24.1 million cases and 160,700 deaths among children under five annually.
In the U.S., around 80% of children under two have received the recommended DTaP vaccine series, 90% of adolescents have received at least one Tdap shot, and only 43% of adults aged 18 and up have received a Tdap vaccine in the last ten years (boosters are recommended every decade).
As the holiday season approaches, health officials urge everyone to get vaccinated to protect themselves and their loved ones from pertussis.
