Pertussis Pneumonia and the Scenario of Re-Emerging Immunopreventable Diseases

Pertussis is an infectious disease caused by Bordetella pertussis . Vaccination, now part of the National Immunization Program, has been essential for containing its spread. The expected epidemiological profile of pertussis is characterized by a concentration of cases in socioeconomically vulnerable populations and in children. However, the current scenario shows a rising incidence in recent years, likely driven by declining vaccination coverage. This report describes a case of B. pertussis infection in a 70-year-old woman with good socioeconomic status. She presented to the emergency department with paroxysmal cough for 7 days, progressing to dyspnea and cyanosis of the extremities. On admission, she was conscious but overall ill-appearing, afebrile, hypoxemic (SpO₂ 86%), and hypotensive. Lung auscultation revealed diffuse wheezing and laryngeal stridor. Chest radiography showed bibasilar opacities and cephalization of pulmonary vessels. Initial labs revealed leukocytosis of 8,440 without immature forms. Differential diagnoses included typical bacterial pneumonia, pertussis, viral pneumonia, and pulmonary embolism. PCR for respiratory viruses and B. pertussis , procalcitonin, and chest CT angiography were ordered. Amoxicillin/clavulanate and azithromycin were initiated to ensure coverage of expected bacteria. CT imaging revealed consolidative inflammatory-infectious pulmonary opacities. Procalcitonin was detectable (0.1 ng/mL) but below the cutoff for bacterial infection (0.25 ng/mL). The viral panel was negative, and PCR for pertussis was positive. A post-infectious inflammatory storm led to acute respiratory failure, posing a high risk of death. Clinical evolution was favorable, and hospital stay lasted 7 days. This case highlights the resurgence of vaccine-preventable diseases. Low vaccination coverage is driving the re-emergence of diseases such as pertussis, necessitating reformulated and intensified immunization strategies. Health professionals play a strategic role in re-emerging diseases and must encourage immunization programs.