Whooping cough cases on the rise, but public awareness of the disease still persists

Following a several-year lull during the pandemic, cases of whooping cough are increasing across the United States. As of Nov. 30, early U.S. data show over 28,000 cases reported this year, or six times as many as in the same period in 2023, according to the Centers for Disease Control and Prevention (CDC).

Whooping cough or pertussis, a highly contagious bacterial infection of the respiratory tract, was one of the most common childhood diseases in the 20^th century and a major cause of childhood mortality, according to the CDC. Until a pertussis vaccine became available in the 1940s, over 200,000 cases were reported annually, the CDC says.

As cases rise, a nationally representative panel survey by the Annenberg Public Policy Center of the University of Pennsylvania finds that many in the public are not familiar with symptoms of the disease. Almost a third of respondents (30%) are not sure if pertussis is the same as whooping cough (it is) and not sure (30%) whether a vaccine exists to prevent it (it does).

The CDC recommends vaccination for everyone against whooping cough, which is spread by coughing or sneezing. The illness may first resemble a common cold but can produce “rapid, violent, and uncontrolled coughing fits” a week to two weeks after symptoms appear. People who are vaccinated may still get whooping cough but generally have a milder illness.

Safety reviews of two main types of whooping cough vaccines – Tdap (tetanus, diphtheria, acellular pertussis), for those 7 years and older, and DTaP (diphtheria, tetanus, and acellular pertussis) for infants and young children – show both to be safe and effective, the CDC reports.

The MMR vaccine, which covers measles, mumps and rubella, is colloquially referred to as the measles vaccine. Instead of speaking about the DTaP and Tdap vaccines and using the unfamiliar term ‘pertussis,’ public health communicators should reiterate that our best defense against whooping cough is the whooping cough vaccine.”

Kathleen Hall Jamieson, director of the Annenberg Public Policy Center (APPC)

What does Tdap protect against?

The Tdap vaccine (tetanus, diphtheria, pertussis) is recommended by the CDC to be given to everyone age 7 and older, including those who are pregnant to protect their newborn.

Yet only half or less of Americans know which diseases the Tdap vaccine protects against. According to the latest Annenberg Public Policy Center health survey, when a nationally representative sample of U.S. adults is provided with a list of diseases and asked which of these diseases the Tdap vaccine protects against, a third of respondents (34%) say they are not sure.

Just 44% selected pertussis or whooping cough, 47% selected diphtheria, and 50% selected tetanus, all correct. The vast majority of respondents rightly rejected several incorrect choices – just 13% said Tdap protects against polio, 10% said pneumococcal disease such as pneumonia or meningitis, 3% selected dengue, and 1% chose Zika.

In total, almost 3 in 10 people (29%) knew all three diseases that the Tdap vaccine protects against and chose none of the incorrect ones.

The survey finds that 85% of respondents say they would be likely to recommend that a child aged 11 to 12 years old in their household or an adult in their family who is due for their 10-year booster get a Tdap vaccine. And 80% indicated that they think the Tdap vaccine is effective at offering protection against tetanus, diphtheria, and pertussis, although 15% were unsure.

Knowing the symptoms of whooping cough

Many in the public lack familiarity with the symptoms of whooping cough – in fact, when the survey respondents are shown a list of symptoms and asked which are for whooping cough, the only one almost universally recognized (83%) is coughing fits. These fits are often followed by a distinctive “whoop” sound when someone gasps for air. Low-grade fever is correctly selected as a symptom by 44%; vomiting after coughing fits by 33%; and runny nose by 30%. Under a third of respondents selected symptoms that are not associated with whooping cough: 30% incorrectly chose headache and 28% incorrectly chose chills. Only 14% said they were not sure of the symptoms.

About half of those surveyed (49%) think that a healthy adult who got whooping cough would be likely to experience moderate (34%) or severe (15%) symptoms, while 21% think the adult would experience mild symptoms, 1% think no symptoms, and 29% are not sure.

APPC’s Annenberg Science and Public Health knowledge survey

The survey data come from the 22^nd wave of a nationally representative panel of 1,771 U.S. adults conducted for the Annenberg Public Policy Center by SSRS, an independent market research company. Most have been empaneled since April 2021. To account for attrition, small replenishment samples have been added over time using a random probability sampling design. The most recent replenishment, in September 2024, added 360 respondents to the sample. This wave of the Annenberg Science and Public Health Knowledge (ASAPH) survey was fielded Nov. 14-24, 2024. The margin of sampling error (MOE) is ± 3.3 percentage points at the 95% confidence level. All figures are rounded to the nearest whole number and may not add to 100%. Combined subcategories may not add to totals in the topline and text due to rounding.