Suppressing Whooping Cough

Whooping cough is caused by bacteria. However, it is the toxins produced by the bacteria, rather than the bacteria themselves, that primarily cause symptoms. The same is true of tetanus and diphtheria. Currently, all three of these diseases can be addressed by a single, combined vaccine. The museum’s collections contain objects that document the unique development of the whooping cough vaccine.

Pertussis, commonly known as whooping cough, is a highly contagious bacterial disease that can last for weeks or months. It is usually spread by coughing and sneezing. Pertussis toxins damage the airways and cause them to swell. Infected people experience severe coughing fits (sometimes coughing hard enough to crack ribs), have trouble inhaling, and are susceptible to pneumonia. The disease is extremely dangerous for young children: before the pertussis vaccine became routine, the disease killed 9,000 American children each year, according to the Centers for Disease Control and Prevention (CDC).

The museum’s collections document the methods Americans used to treat whooping cough, as well as to mitigate the disease’s spread within a community, before a vaccine became available. Many early “patent” medicines claimed to ease the symptoms of whooping cough, or even cure it. Often, whooping cough was only one of the many potentially deadly respiratory diseases that the balms, tonics, or inhalants claimed to address.

The very contagious nature of the disease meant that communities had few options but to quarantine households with members infected by whooping cough. Quarantine signs in the museum’s collection document the knowledge and fear of the particularly harsh toll that the disease takes on young children.

The bacterial cause of pertussis, Bordetella pertussis, was isolated in 1906. Whooping cough caused so many fatalities that finding a vaccine was a national priority. Like influenza, pertussis infection can be accompanied by dangerous secondary infections, which further complicated researchers’ understanding of the disease. During the 1920s and 1930s, many vaccines were tested, with limited success. A vaccine that could be proven effective, and did not produce unacceptable side effects, was elusive. The museum's collection contains examples of these early whooping cough vaccines that proved less than ideal.

From the 1940s through the 1960s, various pertussis vaccines were developed that came into common use. Whole-cell vaccines (which used the entire pertussis organism) became the prevalent variety in the U.S. These whole-cell vaccines represented a compromise: they achieved sufficient efficacy in priming the body to recognize and disable the pertussis toxins; but they retained potential side effects, such as low-level fever and soreness at the injection site, caused by those same toxins present with the bacteria in the vaccine. The significant benefits of the vaccine were judged to outweigh the side effects. Indeed, the World Health Organization reports whooping cough vaccination campaigns during the 1950s and 1960s helped achieve a 90% decrease in pertussis incidence and mortality. The museum’s collections contain many examples of pertussis vaccines from this period.

In the 1990s, safety concerns stemming from the side effects of whole-cell pertussis vaccines led the U.S. to switch to acellular vaccines. Acellular vaccines use only specific components of the bacterium and/or inactivated toxins.

The current whooping cough vaccines are unusual – they are effective, but not as predictably protective or long-lasting as many other vaccines, and when outbreaks of the disease occur even some vaccinated individuals become infected. However, vaccinated people usually display much milder symptoms. In addition, maintaining high vaccination and booster rates is important in suppressing whooping cough outbreaks and to protect those most vulnerable to this dangerous disease. According to current CDC figures, even with hospital treatment, 1 out of 100 pertussis-infected babies under a year old will die.

In the 1940s, a combined vaccine for diphtheria, tetanus, and pertussis was introduced. Different versions of the combined vaccine are used depending on the patient’s age. In the U.S., use of the combined vaccine caused annual pertussis cases to fall from as many as 270,000 to 4,000 or less by the 1980s. The combined vaccine is more convenient for patients, and this convenience also saves lives. Fewer injections translate to fewer missed doses, and therefore more protection in a shorter time.