U.S. whooping cough cases soar to highest level in a decade

Whooping cough continues to surge in the United States, with reported cases soaring to more than 32,000 this year - nearly five times the 6,500 cases recorded during the same period last year - marking the highest levels in a decade.

Health experts cite as main culprits for the increase waning vaccination rates and a loss of broad immunity tracing to coronavirus lockdown protocols.

The disease, caused by the bacterium Bordetella pertussis, is highly transmissible from person to person through the air. Because of their immature immune systems, infants younger than 1 year old are at highest risk of contracting whooping cough - also known as pertussis - and are at most significant risk of severe illness.

Vaccination rates with the DTaP shot - which protects against diphtheria, tetanus and pertussis - declined from March through September 2020 at the height of the coronavirus pandemic. But because people were following pandemic protocols such as masking and social distancing, cases did not soar. Some children who missed getting their shots during that period may never have received them, experts have said.

There are two types of pertussis vaccines in the United States. The DTaP for young children and the Tdap for teenagers and adults.

The DTaP vaccine is administered as a series of five shots to infants and young children up to age 6. DTaP provides protection against illness for 98 percent of children within a year of their final dose, and about 71 percent of children remain protected five years later, according to the Centers for Disease Control and Prevention.

With the nation almost five years removed from the early days of the pandemic, cases are back to pre-pandemic levels, with more than 10,000 cases reported yearly - this year, substantially more than that.

Zachary Rubin, a pediatric immunologist in Illinois, said he has seen children in his clinic with coughs that last for months and said public sentiment toward vaccines has probably fostered immunization hesitancy among some parents.

“We tend to land on the same issue with vaccines, and it’s not just about preventing death,” Rubin said. “It’s how you live with the disease.”

Whooping cough is also known as the 100-day cough, and some people endure prolonged coughing spurts that can cause ribs to fracture.

“The cough is not just affecting your respiratory system,” Rubin said. “It affects your whole body, your mood and your sleep, and it can create more anxiety if you’re missing school or work.”

California, Illinois, New York and Ohio have reported some of the highest rates of whooping cough, and experts say an urgent need exists for increased vaccination efforts and public health initiatives to protect vulnerable populations.

In December, the Department of Health and Human Services launched the Let’s Get Real Campaign to share information with parents about the importance of vaccines and tools for pediatric medicine professionals to educate about childhood vaccines.

“Unless we really take public health measures, I worry starting with the next administration, we’ll see an uptake in the disease,” said Scott Roberts, an infectious-disease physician at Yale School of Medicine.

Health experts worry that the incoming administration could impede efforts to increase vaccination rates among vulnerable populations.

Robert F. Kennedy Jr., whom President-elect Donald Trump selected to lead HHS, will have significant influence over vaccine production and safety. Kennedy has been a longtime anti-vaccine activist, and many health experts express concerns that he could contribute to waning vaccination rates.

Although he has said he is not anti-vaccine, Kennedy has criticized the recommended list of childhood vaccines and promoted debunked claims about autism and vaccines.

Pertussis is challenging to diagnose because early symptoms can resemble a common cold, meaning that many cases go unreported. Roberts said increased testing for the disease does not explain the significant rise in cases this year.

“It’s still the same testing apparatus as last year - there haven’t been any changes in testing surveillance,” Roberts said. “This isn’t a mild uptick. This is an exponential uptick, and that is striking and overcomes any testing bias.”

Testing for pertussis is done by collecting a sample from the back of the throat. That sample can then be analyzed several ways, including through a PCR evaluation, which looks for DNA evidence and can be completed rapidly, or it can be cultured in a laboratory to grow the bacteria, a process that takes longer. In later states of illness, testing can also be done to check for antibodies.

But the tests for whooping cough are expensive. Rubin said in his clinic, he has seen charges for a single test reach hundreds of dollars.

Treating pertussis early is the best way to minimize the severity of illness. Antibiotics such as azithromycin, clarithromycin and erythromycin are recommended by the CDC.

Prevention might become increasingly more difficult if the bacterium evolves to evade vaccines, according to Anita Patel, a pediatric critical care physician at Children’s National Hospital in D.C.

“Waning immunity is part of the picture, but we’re seeing a rise in cases because the vaccine is less effective because it’s evolving to outsmart bacteria,” Patel said.