Lindee Abe, APRN
Whooping cough has been making the rounds again, and there have been reports of increased cases in 2024 across the United States. This results in more patients wanting to be seen for a cough, fearing that this may be the underlying cause. The numbers for 2024 are higher than 2023, but it should be noted that they are only slightly above the number of cases seen in 2019 before the pandemic. During the pandemic, people wore masks and would stay home if they developed a cough, resulting in fewer cases of whooping cough. With the rise in cases of whooping cough in 2024, clinicians should keep this diagnosis as a differential when seeing patients with a cough.
Introduction
Whooping cough is caused by the Bordetella pertussis bacteria and has been around for hundreds of years. Humans are the only host of Bordetella pertussis. Respiratory droplets transmit the virus and frequently infect the nasal mucosa’s epithelial lining. This explains why there was an overall decrease in cases of whooping cough during the pandemic when masking was encouraged. Whooping cough is considered endemic in the United States and typically rises in cases every few years outside of the COVID-19 pandemic. Whooping cough can affect all ages but has a higher mortality in infants and small children.
There is a vaccine available that can decrease the risk of contracting whooping cough and the severity of symptoms. The whooping cough vaccine was developed in the early 1900s but did not become common un?l the mid-1900s. The two available vaccines for whooping cough are Tetanus, diphtheria, and acellular pertussis (Tdap) and Diphtheria, Tetanus, and Pertussis (DTaP). The DTaP vaccine is preferred for patients < 7 years old due to more diphtheria toxoid and pertussis antigen than the Tdap (Drutz and Boom, 2024).
The DTaP is recommended as a series of five immunizations at 2 months, 4 months, 6 months, 15 to 18 months, and 4 to 6 years (Drutz and Boom, 2024). Tdap is the recommended vaccination for adolescents and adults and should be administered every 7 to 10 years as a booster. A booster is needed due to the waning immunity from whooping cough with time. This also means patients with a prior history of natural whooping cough infection should still receive Tdap or DTaP vaccinations based on the guidelines. Additionally, pregnant patients should receive a Tdap vaccination during the third trimester due to the conferred immunity it provides for the newborn child.
The slide above was taken from the Provider Practice Essentials Professional Development Series for Acute Care Providers
Pertussis Stages (Stage 1: Catarrhal Stage)
Whooping cough has three stages of the infection. The first stage is the catarrhal stage, which can last 1 to 2 weeks. This stage is nonspecific and is frequently diagnosed as a viral upper respiratory infection. The symptoms include runny nose, clear eye discharge, low-grade fever, mild cough, fatigue, and sneezing. This is the stage where the patient is considered most infectious. It is ideal if the patient can be diagnosed during this stage to initiate treatment and decrease the spread of the disease, but this rarely occurs unless there is a known exposure.
Stage 2: Paoxysmal Stage
The second stage of infection is the paroxysmal stage, lasting 1 to 6 weeks. This is typically the point where the disease is diagnosed, as it is when the characteristic whooping cough develops. The whooping cough occurs due to severe coughing, resulting in forceful inspiration and creating a whooping sound. The cough during this stage can be so severe that patients have chest pain from the overworked intercostal muscles and, in some cases, even fractured ribs from coughing fits. Patients can also have emesis after coughing fits, hernias, and scleral hemorrhage. Patients can have a leukocytosis during this phase if a CBC is completed, but this is not specific to whooping cough versus another infectious etiology. While a chest X-ray is typically ordered in patients to rule out pneumonia, most patients with whooping cough will have normal chest X-rays.
Stage 3: Convalescent Stage
The final stage is the convalescent stage, which can last up to four weeks. During this phase, the patient slowly begins to improve. The cough can remain throughout this phase but is typically improved. This is the phase during which the patient can be more vulnerable to secondary infections and should be monitored for the development of worsening symptoms after a period of improvement, especially a fever.
Diagnosis and Treatment of Whooping Cough
Diagnosis of whooping cough should be confirmed with Polymerase chain reaction (PCR) testing (Kline et al., 2021). Culture is recommended to confirm positive PCR tests or if PCR testing is unavailable (Kline et al., 2021). However, if there is a high suspicion of whooping cough, treatment can be initiated while awaiting testing results.
Treatment for whooping cough consists of antibiotics and supportive care. It is important to educate the patient that antibiotics are not for symptom improvement but to reduce the spread of whooping cough. Azithromycin is the preferred antibiotic for the treatment of whooping cough (Kline et al., 2021). If patients cannot take macrolide antibiotics, trimethoprim-sulfamethoxazole can also be used. Supportive treatments include increasing fluid intake, rest, humidifiers, and antitussives (e.g., dextromethorphan).
Post-Exposure Prophylaxis
Post-exposure prophylaxis is recommended for all household contacts and high-risk patients (e.g., infants, immune compromised, third-trimester pregnancy) that have had close contact with the infected person. Patients with whooping cough should remain isolated from high-risk individuals until they have completed the entire course of antibiotics. Healthcare providers who have been exposed and have a high risk of severe illness should receive prophylactic treatment.
Summary
Whooping cough is a challenging diagnosis in the clinical setting, especially in acute care settings (e.g., urgent care, emergency room), because it initially presents as a viral illness. This means that clinicians should be asking if there was a potential exposure when seeing patients with cough and continuing to have whooping cough on the differential diagnosis list for patients with cough. Early diagnosis is essential to start patients on antibiotics and minimize the spread of the illness.
References:
Cornia, P., Lipsky, B.A. (2024). Pertussis infec?on in adolescents and adults: Treatment and preven?on.
Retrieved from https://www.uptodate.com/contents/pertussis-infec?on-in-adolescents-and-adults-
treatment-andpreven?on?search=whooping%20cough%20prophylaxis&source=search_result&selectedTitle=1%7E150
&usage_type=default&display_rank=1#H12882709
Drutz, J.E. & Boom, J.A. (2024). Diphtheria, tetanus, and pertussis immuniza?on in children 6 weeks
through 6 years of age. Retrieved from https://www.uptodate.com/contents/diphtheria-tetanus-andpertussis-immuniza?on-in-children-6-weeks-through-6-years-of-age/print
Kline, J.M., Smith, E.A., Zavala, A. (2021). Pertussis: Common ques?ons and answers. American Family
Physician. 2021;104(2):186-192. Retrieved from https://www.aafp.org/pubs/afp/issues/2021/0800/p186.html#:~:text=Patients%2011%20years%20or%20older,convey%20immunity%20to%20the%20newborn
