References:
- Global Infectious Diseases and Epidemiology Online Network: Infectious Diseases of the Philippines, 2013 eBook Edition, ISBN 978-1-61755-582-4, by Stephen Berger. Accessed here.
- Saunders Comprehensive Review for the NCLEX-RN Examination, 9th Edition, ISBN 978-032-37-9530-2, by Linda Anne Silvestri, Angela E. Silvestri, and Jessica Grimm (Ch. 41, pp. 511–512)
- Wong’s Nursing Care of Infants and Children, 11th Edition, ISBN 978-0-323-54939-4, by Marilyn J. Hockenberry, David Wilson, and Cheryl C. Rodgers (Ch. 6, p. 182; Ch. 26, pp. 912–913)
- Brunner & Suddarth’s Textbook of Medical-Surgical Nursing, 15th Edition, ISBN 978-197-51-6103-3, by Janice L. Hinkle, Kerry H. Cheever, and Kristen J. Overbaugh (Ch. 66, pp. 5732–5733)
Pertussis, or whooping cough, is an acute respiratory tract infection caused by Bordetella pertussis that occurs primarily in children younger than 4 years of age who have not been immunized. It is highly contagious and is particularly threatening in young infants, who have a higher morbidity and mortality rate.
- It presents as a URI, and cough symptoms (may be mild, more severe if unimmunized) develop. It persists for 6 to 10 weeks and can result in encephalopathy, seizures, pneumonia, rib fractures (adolescents), bleeding into the conjunctive, or even death (infants).
- Infants less than 6 months of age may not come in to the practitioner with the typical cough; in this age-group, apnea is a common presenting manifestation.
- Likewise, older children often manifest the disease with a persistent cough and the absence of the characteristic whoop.
Pathophysiology
B. pertussis is transmitted by droplets. The bacteria easily attach to pharyngeal epithelial cells, where they release a number of antigens, toxins, and other substances that trigger the immune system. Because most of the disease manifestations are caused by this immune reaction, patients are usually contagious only early in the disease (when the bacteria are still present) and not during the protracted period of cough (when the immune reaction is causing the pathology).
| Agent | BACTERIUM. Bordetella pertussis, an aerobic gram-negative coccobacillus. |
| Reservoir | Human |
| Vector | None |
| Vehicle | Air Infected secretions |
| Incubation Period | 7 to 10 days (As early or late as 5 to 21 days) |
| Diagnostic Tests | Culture and direct fluorescence (nasopharynx) Alert laboratory when suspected Serology Polymerase chain reaction assay (via nasopharyngeal secretions) |
| Typical Adult Therapy | Respiratory precautions. Erythromycin 500 mg QID X 10d. Alternatives: Azithromycin, Clarithromycin |
| Typical Pediatric Therapy | Respiratory precautions. Erythromycin 10 mg/kg QID X 10d. Alternatives: Azithromycin, Clarithromycin |
| Vaccines | DTaP (Pediatric formulation, 2 months to 6 years) DTP Tdap (Teen and adult formulation, >11 years, every 10 years; pregnant women in early pregnancy) |
| Clinical Hints | Coryza, paroxysmal cough, occasional pneumonia or otitis; lymphocytosis; most often diagnosed in young children; epistaxis and subconjunctival hemorrhage often noted; seizures (below age 2); case-fatality rate = 0.5%. |
| Synonyms | Bordetella holmesii, Bordetella parapertussis, Bordetella pertussis, Coqueluche, Keuchhusten, Kikhosta, Kikhoste, Kinkhoest, Parapertussis, Pertosse, Syndrome coqueluchoide, Tos convulsa, Tos farina, Tosse convulsa, Tussis convulsa, Whooping cough |
WHO Case Definition for Surveillance
Clinical case definition: a person with a cough lasting at least 2 weeks with at least one of the following:
- Paroxysms (i.e. fits) of coughing
- Inspiratory whooping
- Post-tussive vomiting (i.e. vomiting immediately after coughing)
- Without other apparent cause
Laboratory criteria for diagnosis
- Isolation of Bordetella pertussis (clinical culture of nasopharyngeal specimen), or
- Detection of genomic sequences by polymerase chain reaction (PCR)
- Serologic testing, although less reliable, can also strengthen the diagnostic suspicion.
Case classification
- Suspected: A case that meets the clinical case definition.
- Confirmed: A person with a cough that is laboratory-confirmed.
Clinical Manifestations
- Following an incubation period of 7 to 10 days (range 6 to 20) the patient develops coryza and cough (the catarrhal stage). Other upper respiratory tract infection symptoms (sneezing, lacrimation, low-grade fever) may be present. Symptoms continue for 1 to 2 weeks, when dry, hacking cough becomes more severe.
- The source of the infectious agent are discharges from the respiratory tract of an infected person. This makes the catarrhal stage, where discharge from respiratory secretions occurs, the period of most communicability. Transmission occurs when direct contact or droplet spread from infected person or indirect contact with freshly contaminated articles.
- After one to two weeks, the cough progresses into the paroxysmal stage. Cough is most common at night, consisting of short, rapid coughs followed by sudden inspiration associated with a high-pitched crowing sound or “whoop”; during paroxysms, cheeks become flushed or cyanotic, eyes bulge, and tongue protrudes; paroxysm may continue until thick mucus plug is dislodged.
- Post-tussive vomiting is common, and young children and older infants may exhibit an inspiratory “whoop.”
- Among infants younger than six months, apnea is common and the whoop may be absent. This age group may have difficulty maintaining adequate oxygenation with the amount of secretions and frequent vomiting of mucus and formula or breast milk.
- Adolescent and adult pertussis infection may occur with varying manifestations. Cough and whoop may be absent, however, as many as 50% of adolescents may have a cough for up to 10 weeks. They may feature difficulty breathing and post-tussive vomiting.
- The paroxysmal stage lasts three to four weeks (ranges from one to six), and is followed by a convalescent stage.
- The convalescent stage, where signs and symptoms gradually recede, lasts for two to four weeks.
Complications
Infants are at increased risk of complications from pertussis, while pertussis among adolescents and adults tends to be milder and may be limited to a persistent cough.
- Over 70% of infants younger than 6 months require hospitalization.
- Complications of pertussis can include secondary bacterial pneumonia (the most common cause of death in pertussis), seizures and encephalopathy.
- Other, less serious complications include otitis media, weight loss, and dehydration.
- Severe coughing can lead to pneumothorax, hemorrhaging (scleral, conjunctival, epistaxis; pulmonary hemorrhage in neonates), subdural hematoma, acute carotid dissection with stoke, hernia (umbilical, inguinal), and rectal prolapse.
- In adolescents, syncope, sleep disturbance, rib fractures, incontinence, and pneumonia may occur.
- Pertussis in adults is often characterized by unexplained prolonged cough.
- Pertussis-RSV infection is common.
- Rare cases of acute disseminated encephalomyelitis and hemolytic-uremic syndrome have been ascribed to pertussis.
- Human Bocavirus infection may mimic the symptoms of pertussis.
Parapertussis
Parapertussis is caused by Bordetella parapertussis, and shares many of the clinical features of pertussis. 70% of infections are asymptomatic.
Medical Management
- Diagnosis: Pertussis is diagnosed via culture or polymerase chain reaction assay using nasopharyngeal secretions.
- Antibiotic Therapy: Most children can be cared for at home on oral antibiotics (e.g., erythromycin, azithromycin, clarithromycin). The antibiotic trimethoprim sulfamethoxazole may also be used (CDC, 2020w).
- Prophylaxis: Antibiotics in the early stage may result in a milder form of the infection, but they also limit its spread to others. Household members, high-risk individuals (immunodeficiency, pregnancy, chronic lung conditions, infants, or those who care for infants), and close contacts (within 3 feet of a person who has symptoms) may be treated with one of the previously mentioned agents to reduce the risk of disease. These individuals should report any signs of an upper respiratory tract infection.
- Vaccination: Current belief is that childhood immunizations for pertussis do not confer lifelong immunization to adolescents and adults, so a pertussis booster is recommended for adolescents.
- DTaP, a pediatric formulation, is given to children 2 months to 6 years of age.
- Tdap, a teen and adult formulation, is given to children 11 years or older, as a booster every 10 years, to pregnant women early in pregnancy, and regularly (every 10 years) for adults around children 12 months or younger.
Nursing Care Management
- Transmission-based Precautions: Institute droplet and contact precautions in the hospital; isolate child during the catarrhal stage (period of greatest communicability). Isolation with droplet precautions are kept in place for at least five days of appropriate therapy.
- Diagnostics: Obtain nasopharyngeal culture for diagnosis.
- Antimicrobial Therapy: Administer therapy as prescribed. Encourage compliance with antibiotic therapy for household contacts.
- Minimize Irritants: Reduce environmental factors that cause coughing spasms, such as dust, smoke, and sudden changes in temperature.
- Supportive Care:
- Ensure adequate hydration and nutrition. Offer small amounts of fluid frequently.
- Suction as needed to prevent choking on secretions. Provide humidified oxygen if needed. Observe for signs of airway obstruction (e.g., increased restlessness, apprehension, retractions, cyanosis).
- Position the infant on side to decrease change of aspiration with vomiting.
- Monitor cardiopulmonary status (via monitor as prescribed) and pulse oximetry.
- Prevention: Immunity to pertussis is not transferred from parent to child. The tetanus-diphtheria-acellular pertussis (Tdap) vaccine would be administered to birth parent in the postpartum period and those in close contact with the infant to prevent the spread of pertussis to infants.