Pertussis (whooping cough) nursing: assessment, interventions, and NCLEX review

Pertussis — whooping cough — is caused by Bordetella pertussis, a gram-negative coccobacillus that remains one of the most contagious respiratory pathogens in human medicine, with a basic reproduction number (R0) of 12–17 in unvaccinated populations. Despite widespread childhood vaccination with DTaP, pertussis never retreated to historical rarity: tens of thousands of cases are reported in the United States every year, and the true incidence is estimated to be substantially higher because atypical presentations in vaccinated adolescents and adults are frequently misdiagnosed as bronchitis or prolonged viral upper respiratory infections. For nursing students, pertussis tests clinical recognition across its three distinct disease stages, infection control decision-making (the droplet vs. airborne distinction is a recurring NCLEX target), antibiotic pharmacology (the erythromycin-infantile pyloric stenosis association is frequently tested), and high-risk population management — particularly the life-threatening presentations in infants under 6 months, where the classic inspiratory whoop may be absent and apnea may be the only clinical sign.

This reference covers pathophysiology, the catarrhal-paroxysmal-convalescent stage sequence, nursing assessment priorities, isolation and infection control, medications, special populations, vaccination, complications, and six NCLEX-style practice questions with full rationales. Use alongside the tetanus nursing reference for comparison of other DTaP/Tdap vaccine-preventable diseases, the influenza nursing reference for droplet precaution comparison, the meningococcal meningitis nursing reference for another vaccine-preventable disease cluster, the pneumonia nursing reference for management of the most common pertussis complication, and the sepsis nursing reference for secondary infection risk.

Fast-scan summary: pertussis

Pathophysiology

The organism

Bordetella pertussis is a small, gram-negative coccobacillus that is an obligate human pathogen — it has no animal reservoir, and all transmission is person to person via respiratory secretions. Unlike many gram-negative bacteria that primarily cause disease through endotoxin (lipopolysaccharide), B. pertussis is a virulence-factor-rich organism that uses a coordinated suite of adhesins and toxins to colonize the respiratory epithelium and evade host immune responses.

The two virulence factors most clinically important for nursing students are:

Filamentous hemagglutinin (FHA): The primary adhesin. FHA is a long, filamentous surface protein that binds the organism tightly to ciliated respiratory epithelial cells, particularly in the trachea and bronchi. This attachment is what initiates colonization and protects B. pertussis from mucociliary clearance. FHA also helps the organism bind to macrophages in a way that actually suppresses macrophage killing — a key immune evasion strategy.

Pertussis toxin (PT): The principal toxin responsible for the systemic effects of pertussis. Pertussis toxin is an ADP-ribosyltransferase that permanently inactivates Gi-coupled signaling proteins in host cells. Two consequences are especially clinically significant:

1. Ciliostasis: Pertussis toxin and a second toxin (tracheal cytotoxin) cause progressive destruction of the ciliated epithelium of the respiratory tract. With cilia paralyzed and then shed, the mucociliary escalator — the airway’s primary clearance mechanism — is disabled. Mucus, bacteria, and debris accumulate in the airways, triggering the uncontrolled cough paroxysms that define the illness. Cilia take weeks to regenerate, which explains why coughing persists through the convalescent stage long after bacterial clearance.

2. Lymphocytosis: Pertussis toxin blocks lymphocyte trafficking by inhibiting Gi-coupled chemokine receptors on lymphocytes. Lymphocytes cannot exit the bloodstream to migrate into tissues, and they cannot leave lymph nodes normally. The result is a striking accumulation of lymphocytes in the peripheral blood — a characteristic lymphocytosis that can reach 20,000–50,000 cells/μL or higher. This finding is not a sign of viral infection (as leukocytosis with lymphocyte predominance is often interpreted); it is a direct toxin effect, and it is one of the most diagnostically helpful lab findings in pertussis.

Why the cough is paroxysmal

The inspiratory whoop of pertussis is not itself a cough — it is the forceful inspiratory effort that follows a paroxysm (a rapid burst of coughs on a single exhalation). During a paroxysm, the patient expels air repeatedly until forced to inhale. The sudden inhalation through a partially obstructed, mucus-laden upper airway against the background of ciliostasis-induced secretion accumulation produces the high-pitched “whoop.” Not all patients produce an audible whoop: infants are physiologically unable to generate the airway pressure differential required, and vaccinated adolescents and adults may have attenuated disease without the classic sound.

The three clinical stages

Pertussis progresses through three distinct stages. Stage recognition is a core NCLEX competency because nursing interventions, infection control priorities, and diagnostic yield differ by stage.

Catarrhal stage (weeks 1–2)

The catarrhal stage is clinically indistinguishable from a common cold or mild upper respiratory infection. The patient presents with:

• Low-grade fever (often absent or minimal)
• Coryza (runny nose)
• Lacrimation
• Mild cough, progressively worsening
• No characteristic whooping at this stage

This stage represents the greatest infection control threat. B. pertussis is present at maximum density in respiratory secretions, yet the patient appears to have an ordinary cold. Household transmission and healthcare worker exposure most commonly occur here, before the diagnosis is even considered. Any patient presenting with URI symptoms who has known contact with a confirmed pertussis case, who is unvaccinated or incompletely vaccinated, or who is an infant without age-appropriate vaccination must trigger prompt isolation and consideration of empirical antibiotic treatment.

Antibiotics initiated during the catarrhal stage can abort or significantly attenuate disease progression.

Paroxysmal stage (weeks 2–8)

The paroxysmal stage is the classic phase of pertussis and the one nursing students are expected to recognize in clinical scenarios. Defining features:

Coughing paroxysms: Rapid, staccato bursts of coughs without inhalation between each one. A single paroxysm may involve 5–25 individual coughs in rapid succession, lasting 1–3 minutes. Paroxysms are exhausting and can be triggered by feeding, crying, cold air, activity, or suction. Patients may appear well between episodes.

Inspiratory whoop: The characteristic high-pitched sound on forceful inhalation immediately following a paroxysm. More common in school-age children than in infants or adults. Its absence does not exclude the diagnosis.

Post-tussive vomiting: Vomiting that occurs immediately after a paroxysm (from gagging on mucus and the physical effort of coughing) is present in approximately 50% of cases and is an important clinical clue — especially in adults where the whoop may be absent.

Cyanosis: During severe paroxysms, particularly in infants, patients may become cyanotic from hypoxia. In young infants, apnea — not coughing at all — may be the primary presentation, occurring during or after paroxysms.

Between episodes: Patients are often afebrile and appear well between paroxysms, which can mislead clinicians into underestimating severity.

Antibiotics started during the paroxysmal stage reduce contagiousness (bacterial shedding ceases within 5 days) but do not shorten the duration of paroxysms. The cough paroxysms persist because they are driven by ciliostatic toxin effects on the airway epithelium, not by ongoing bacterial replication. This distinction is high-yield for NCLEX.

Convalescent stage (weeks 6–10+)

The convalescent stage is defined by gradual improvement in cough frequency and severity. However, paroxysms do not stop abruptly — they diminish over weeks to months. Coughing episodes may recur or worsen transiently during subsequent respiratory infections (the “pertussis recrudescence” phenomenon) because the regenerating ciliated epithelium remains vulnerable during intercurrent illnesses.

The term “100-day cough” refers to the historical observation that symptoms can persist for approximately 100 days (roughly 14 weeks) from onset — a duration that far exceeds what most clinicians or patients expect from a respiratory infection, and that often leads to delayed diagnosis.

Nursing assessment

Vital signs and respiratory monitoring

• Temperature: Often normal or low-grade, especially in vaccinated patients. High fever should prompt evaluation for secondary bacterial pneumonia.
• Respiratory rate: Monitor closely before, during, and after paroxysms. Sustained tachypnea between paroxysms suggests developing pneumonia or hypoxemia.
• Oxygen saturation: Continuous pulse oximetry in hospitalized patients, particularly infants. Desaturation during paroxysms is expected; persistent hypoxemia between episodes is a warning sign.
• Heart rate: Bradycardia during paroxysms in infants is an ominous sign associated with hypoxic cardiovascular compromise.

Respiratory assessment priorities

• Character and frequency of coughing episodes — document paroxysm duration, post-tussive vomiting, presence/absence of whoop
• Work of breathing between paroxysms — retractions, nasal flaring, accessory muscle use
• Breath sounds — decreased aeration or new crackles suggest developing pneumonia
• Mucus color and quantity — thick, ropy secretions typical; purulent sputum suggests secondary infection
• Cyanosis — perioral cyanosis or central cyanosis during paroxysms requires immediate intervention

Laboratory findings

CBC with differential: The hallmark laboratory finding in pertussis is a marked lymphocytosis. In classic disease:

• WBC may reach 15,000–60,000 cells/μL or higher in severe cases
• The differential shows lymphocyte predominance (often >70% lymphocytes)
• This is a direct effect of pertussis toxin, not a reflection of a co-existing viral illness
• An unexplained lymphocytosis in a patient with paroxysmal cough should raise strong clinical suspicion for pertussis

Nasopharyngeal culture or PCR: PCR (polymerase chain reaction) from a nasopharyngeal swab or wash is the preferred diagnostic test and has the highest sensitivity, particularly in the catarrhal and early paroxysmal stages. Culture remains the gold standard for public health reporting but requires specialized media and takes 7–10 days. Serology (anti-PT IgG) is useful in later disease when PCR yield declines.

Infant vs. adult presentation differences

High-risk groups

• Infants under 6 months: Too young to have completed primary DTaP series; highest mortality group
• Unvaccinated or incompletely vaccinated individuals of any age
• Vaccinated adolescents and adults with waning immunity: Pertussis immunity from both natural infection and vaccination is not lifelong; protection wanes significantly within 4–12 years
• Immunocompromised patients: May have prolonged shedding and atypical presentations
• Pregnant women: Risk of preterm delivery from severe coughing paroxysms; Tdap in pregnancy protects the newborn through passive antibody transfer before the infant can receive their own primary series

Nursing interventions

Airway management

Airway management is the central nursing priority in pertussis, particularly for hospitalized infants and young children.

Cluster care: Paroxysms are triggered by stimulation. Cluster all nursing interventions — vital signs, medication administration, repositioning, feeding — to minimize the number of times the patient is disturbed. Each unnecessary interruption risks triggering a coughing episode.

Suction equipment at bedside: Thick mucus secretions combined with post-tussive vomiting create aspiration risk. Have suction equipment set up and immediately accessible. Suction only as needed — excessive suctioning triggers additional paroxysms.

Positioning: Elevate the head of the bed. For infants, positioning in a semi-upright or lateral position during and after feedings reduces aspiration risk from post-tussive vomiting.

Oxygen therapy: Administer supplemental oxygen as needed to maintain target saturation (typically ≥95% in children and adults; follow neonatal parameters for premature infants). High-flow nasal cannula or non-rebreather mask may be required during severe paroxysms. Be prepared for rapid desaturation.

Resuscitation readiness: For infants, have resuscitation equipment immediately accessible at the bedside. Bradycardia and apnea can be sudden. Brief stimulation (tactile) is often sufficient to restart breathing in mild apnea episodes; have bag-valve-mask available for events that do not self-terminate.

Infection control

Pertussis is highly contagious. Implement precautions immediately on clinical suspicion — do not wait for laboratory confirmation.

Droplet precautions: The CDC recommends droplet precautions as standard for pertussis care. This requires:

• Surgical mask for all healthcare workers within 3 feet of the patient
• Private room or cohorting with other confirmed pertussis patients
• Gloving and gowning per contact precautions in addition to droplet when direct patient contact occurs

Airborne precautions considerations: During aerosol-generating procedures — such as suctioning, bronchoscopy, or high-flow oxygen delivery — some institutional protocols add airborne precautions (N95 respirator, negative-pressure room). Follow your facility’s infection control policy.

Discontinuation criteria: Isolation can be discontinued after 5 days of effective antibiotic therapy or after 3 weeks from cough onset if antibiotics were not given or are contraindicated.

Contact tracing and chemoprophylaxis: All household contacts and close contacts of a confirmed or suspected pertussis case should receive post-exposure prophylaxis with azithromycin regardless of vaccination status, ideally within 21 days of exposure.

Nutrition and hydration management

Post-tussive vomiting combined with anorexia from the exhaustion of repeated paroxysms creates significant nutritional and hydration risk.

• Offer small, frequent, high-calorie feedings; avoid large-volume meals that fill the stomach and worsen vomiting
• Time feedings for immediately after a paroxysm, when the next episode is least likely
• In infants with significant vomiting or poor oral intake, IV fluids or nasogastric feeding may be required to maintain hydration and caloric goals
• Monitor weight daily in hospitalized infants
• Document intake and output carefully; dehydration is a complication that compounds respiratory compromise

Monitoring for complications

• Vital signs and oxygen saturation every 2–4 hours minimum; continuous pulse oximetry for infants
• Respiratory assessment before and after each paroxysm
• Neuro checks in infants for signs of encephalopathy (altered consciousness, seizures)
• Report new fever, purulent sputum, or worsening respiratory status immediately — these suggest secondary pneumonia
• Daily weight in pediatric and infant patients

Medications

See the medication rights nursing reference for antibiotic administration safety practices.

Critical pharmacology point: Antibiotics in pertussis serve primarily to reduce transmission (by eliminating B. pertussis from respiratory secretions) and, if given in the catarrhal stage, to attenuate disease. They do not reverse the toxin-mediated ciliostasis that causes paroxysmal coughing. Once the paroxysmal stage is established, patients will continue coughing for weeks regardless of antibiotic treatment. This must be clearly communicated to patients and families to prevent unnecessary antibiotic requests and inappropriate course completion concerns.

Special populations

Infants under 6 months

Infants younger than 6 months carry the highest burden of pertussis mortality and severe morbidity in the United States. Several factors compound their vulnerability:

• No completed primary series: The DTaP schedule begins at 2 months; infants younger than this are completely unprotected by vaccine, and even infants who have received one or two doses have not achieved full immunity.
• Atypical presentation: The classic whoop is usually absent. Apnea — episodes of cessation of breathing, sometimes without coughing at all — may be the initial or dominant presentation. Infants can be brought in for “breathing problems” or brief resolved unexplained events (BRUEs) before pertussis is considered.
• Extreme lymphocytosis: Counts above 50,000 cells/μL occur in severe infant pertussis and are associated with leukostasis, pulmonary hypertension, and cardiovascular collapse. Exchange transfusion or leukoreduction has been used in extreme cases, though evidence for mortality benefit is limited.
• ICU admission: Many infants with pertussis require intensive care unit admission, with a proportion requiring mechanical ventilation for respiratory failure or apnea management.

For nursing students, the key takeaway is that any infant with paroxysmal cough, apnea, or post-tussive vomiting in the context of a febrile household illness should be considered for pertussis until proven otherwise.

Pregnancy

• Pertussis in pregnant women can cause preterm labor and delivery from the physical stress of severe coughing paroxysms.
• Azithromycin is the antibiotic of choice in pregnancy.
• Tdap vaccination at 27–36 weeks of every pregnancy is recommended by the ACIP (Advisory Committee on Immunization Practices), regardless of prior Tdap vaccination history. This timing maximizes transplacental antibody transfer to the infant, providing passive protection during the first weeks of life before the primary DTaP series can begin.

Adults with waning immunity

Adolescents and adults who received childhood DTaP, or who had a previous natural infection, are not permanently protected. Vaccine-derived immunity declines significantly over 4–12 years. Adults who develop pertussis typically present with a prolonged cough illness — often lasting 4–8 weeks — without the dramatic whoop, leading to misdiagnosis as bronchitis, post-nasal drip, or atypical pneumonia. Adults are often the source of transmission to unvaccinated or incompletely vaccinated infants in the household.

Vaccination

Primary series (children): DTaP

DTaP (diphtheria, tetanus, acellular pertussis) is an inactivated combination vaccine containing acellular pertussis antigens — including detoxified pertussis toxin and filamentous hemagglutinin — rather than whole killed organisms (as in the older DTP vaccine). The acellular formulation has substantially fewer systemic side effects than whole-cell DTP while maintaining good immunogenicity.

The recommended primary series schedule:

• 2 months
• 4 months
• 6 months
• 15–18 months
• 4–6 years

Five doses are required for full primary series completion. Each dose builds on the previous and is required for complete protection. Children who miss doses should have vaccination resumed without restarting the series.

See the tetanus nursing reference for complementary detail on the diphtheria and tetanus components of this combined vaccine.

Tdap booster (adolescents and adults)

Tdap (tetanus, reduced-dose diphtheria, acellular pertussis) is the adult/adolescent formulation. It contains lower antigen doses than DTaP. The lower pertussis antigen dose is deliberate — higher doses cause unacceptably high rates of local reactions in older individuals who have had prior antigen exposure.

• One dose of Tdap recommended at 11–12 years for adolescents
• Adults who have never received Tdap should receive one dose as soon as possible
• Pregnant women: one Tdap dose at 27–36 weeks of every pregnancy, regardless of prior Tdap or Td history
• Healthcare workers: Tdap recommended if not previously received; critical for workers in neonatal and pediatric units (cocoon strategy)

The cocoon strategy

The cocoon strategy refers to vaccinating all close contacts of a newborn infant — parents, siblings, grandparents, household members, and regular caregivers — with Tdap before or immediately after the infant’s birth. The goal is to surround (“cocoon”) the infant with immune individuals during the window of maximum vulnerability before the primary DTaP series is completed. Healthcare workers in neonatal units are considered part of this strategy.

Limitations of the cocoon strategy: it requires vaccinating multiple individuals, compliance is imperfect, and protection is indirect. Maternal Tdap in pregnancy (described above) provides more reliable direct passive protection to the infant through transplacental IgG transfer and is now the preferred primary intervention.

Isolation and infection control

Precaution type

The CDC recommends droplet precautions as the standard isolation category for pertussis. Key elements:

• Private room preferred; cohorting with other confirmed pertussis patients is acceptable
• Healthcare workers must wear a surgical mask when within 3 feet of the patient
• Apply contact precautions (gloves, gown) when direct patient care involves potential secretion contact

For aerosol-generating procedures (suctioning, bronchoscopy, nebulization, high-flow oxygen delivery), some institutional protocols require upgrading to airborne precautions (N95 respirator, negative-pressure room). This is an area of inconsistency across guidelines — NCLEX questions typically follow CDC’s droplet precaution standard, but clinical facilities may apply additional airborne measures based on procedure type.

Isolation discontinuation

A patient with pertussis may be removed from isolation when either of the following criteria is met:

• 5 days after effective antibiotic therapy has begun (bacterial shedding ceases within approximately 5 days of macrolide treatment)
• 21 days after cough onset, if antibiotics were not given (natural shedding decline occurs over approximately 3 weeks from symptom onset)

Reporting requirements

Pertussis is a notifiable disease in all 50 states. Confirmed and probable cases must be reported to the local or state health department, which will initiate contact tracing and coordinate post-exposure prophylaxis for close contacts.

Complications

NCLEX practice questions

Question 1

A nurse is caring for a 2-month-old infant admitted with a 10-day history of cough episodes followed by brief apnea. The mother reports the infant becomes blue during coughing episodes and vomits afterward. Which isolation precaution should the nurse initiate immediately?

A. Standard precautions only B. Airborne precautions C. Droplet precautions D. Neutropenic precautions

Question 2

A nurse is reviewing the complete blood count (CBC) of a patient with a 3-week history of severe paroxysmal cough. The results show: WBC 38,000 cells/μL with 75% lymphocytes. Which interpretation is most accurate?

A. This finding is inconsistent with pertussis and suggests a concurrent viral infection B. This marked lymphocytosis is a characteristic finding in pertussis caused by pertussis toxin blocking lymphocyte trafficking C. The patient likely has leukemia, which should be the primary diagnosis D. This is a normal finding in a patient with any respiratory infection

Question 3

A nurse is preparing to administer antibiotics to a 3-week-old infant diagnosed with pertussis. Which antibiotic order requires the nurse to immediately clarify with the prescriber before administration?

A. Azithromycin oral suspension B. Erythromycin ethylsuccinate C. Clarithromycin oral suspension D. TMP-SMX oral suspension

Question 4

A parent asks the nurse why their child who completed the DTaP series at age 6 was still diagnosed with pertussis at age 16. Which response is most accurate?

A. “The DTaP vaccine provides only 30% protection — most vaccinated children still get whooping cough.” B. “Your child likely received a counterfeit vaccine. The real DTaP would have provided complete lifelong protection.” C. “Immunity from both the DTaP vaccine and natural infection wanes over time. Protection typically declines significantly within 4–12 years, which is why a Tdap booster is recommended at age 11–12.” D. “Your child’s immune system did not respond to the vaccine — this is a known failure in approximately half of all recipients.”

Question 5

A nurse caring for a hospitalized child in the paroxysmal stage of pertussis is developing a care plan. Which intervention is the highest priority?

A. Schedule all nursing care activities together to minimize patient stimulation between paroxysms B. Perform hourly suctioning to remove secretions and prevent airway obstruction C. Place the child in Trendelenburg position to facilitate postural drainage D. Encourage aggressive oral hydration during paroxysms to replace losses from vomiting

Question 6

A nurse is assessing a 6-week-old infant admitted for evaluation of “breathing pauses.” The parent reports a mild runny nose for one week, followed by episodes where the infant stops breathing for 15–30 seconds. The infant has not received any vaccinations. Which assessment finding best supports a diagnosis of pertussis?

A. Temperature of 39.8°C (103.6°F) B. WBC 52,000 cells/μL with lymphocyte predominance on differential C. Prominent inspiratory whoop on auscultation during coughing D. Purulent nasal discharge

This reference was written by Lindsay Smith, AGPCNP. Clinical information is sourced from CDC Pertussis guidelines, ACIP vaccine recommendations, and peer-reviewed literature on Bordetella pertussis pathophysiology and clinical management. For complete antibiotic dosing, consult current institutional formulary guidelines.