United States: Whooping cough cases have surged to more than three times the number seen at this point last year, according to the Centers for Disease Control and Prevention (CDC). So far this year, there have been 10,865 reported cases of whooping cough, or pertussis, compared to 2,918 cases in the same period of 2023. This year’s figures are closer to the 8,271 cases recorded by this time in 2019, suggesting a return to pre-pandemic levels.
Doctors note that whooping cough cases had been unusually low in recent years, likely due to COVID-19 mitigation measures such as masking, remote learning, and social distancing. Dr. Mike Patrick, an emergency medicine physician at Nationwide Children’s Hospital in Columbus, Ohio, explained that these precautions greatly reduced transmission. “During the pandemic, we saw a significant drop in pertussis transmission because people weren’t around each other as much. Now, as we return to normal activities, we’re seeing the expected rise in cases,” he told ABC News. He added that without vaccinations, the numbers would be even higher.
Dr. Lori Handy, an infectious diseases physician at Children’s Hospital of Philadelphia, observed that the increase in whooping cough cases mirrors trends seen with other respiratory illnesses as pandemic-related restrictions have been lifted. “It’s somewhat surprising that it took this long, given that many measures were relaxed nearly two years ago,” she said. “We saw a spike in RSV cases in 2022, and now whooping cough seems to be following that trend, returning to what we saw in 2019.”
Whooping cough is a highly contagious respiratory illness caused by the bacterium Bordetella pertussis. These bacteria attach to the cilia, tiny hair-like structures in the upper respiratory tract that help clear mucus and debris, and release toxins that damage these cilia, leading to swelling and a severe cough. “The swelling and damage to the cilia cause a persistent cough as the body tries to clear the airway,” explained Dr. Patrick. “In babies, this can lead to difficulty breathing, and when they finally take a breath after coughing, it creates the characteristic ‘whoop’ sound.”
Whooping cough spreads through coughing and sneezing, with infected individuals potentially being contagious for weeks without realizing it. Early symptoms resemble a common cold—runny nose, cough, and low-grade fever—but can progress to intense coughing fits lasting up to 12 weeks. The illness can be treated with antibiotics, and early treatment can reduce its severity. Most symptoms can be managed at home.
Infants under one year, pregnant women, and immunocompromised individuals are at the highest risk for severe illness. “In young children, particularly infants, whooping cough can cause apnea, hospitalization in intensive care, and even death,” said Dr. Robert Frenck, a professor of pediatrics at Cincinnati Children’s Hospital. “This is not a harmless infection; it can be very serious and even fatal.”
The introduction of the whooping cough vaccine in the late 1940s led to a dramatic decrease in cases, with a more than 90% reduction compared to the pre-vaccine era when around 200,000 cases and up to 9,000 deaths occurred annually among children.
Today, two types of vaccines protect against whooping cough: the DTaP vaccine for babies and young children, and the Tdap vaccine for older children, adults, and pregnant women. A recent CDC report found that exemptions from routine childhood vaccinations, including the DTaP vaccine, were at their highest level during the 2022-23 school year. Dr. Frenck emphasized that the rise in whooping cough cases highlights the importance of vaccines but encouraged vaccine-hesitant parents to ask questions. “Parents want to do what’s best for their children, and there has been a lot of misinformation about vaccines. I recommend talking with your healthcare provider to get accurate information and feel comfortable about vaccinating your children. Vaccines are well-tested, safe, and effective.”
Dr Handy also urged everyone eligible to get vaccinated and advised healthcare providers to be vigilant for pertussis cases. “Recognize that we’re back to where we were five years ago,” she said. “Testing and public health measures are key to preventing the spread of whooping cough.”