Atypical pertussis: Family cluster case series and primary care management strategies

Pertussis, caused by Bordetella pertussis, is a highly contagious respiratory illness experiencing a resurgence globally, particularly in adolescents, and adults. General practitioners (GPs) in primary care settings are crucial for early detection and control, yet often face challenges in diagnosing atypical presentations. This case series describes a family cluster of atypical pertussis managed by a community health service center in Shenzhen, China. A 42-year-old male (Case 1) initially presented with a 10-day history of persistent, dry cough, lacking characteristic paroxysmal coughing and fever, leading to initial misdiagnosis. Subsequent targeted respiratory pathogen testing revealed Bordetella pertussis. Prompt investigation identified two additional family members with confirmed pertussis: his 43-year-old wife (Case 2) and 14-year-old son (Case 3), both exhibiting atypical cough symptoms. Two other asymptomatic family members (Cases 4 and 5) showed positive pertussis antibodies, suggesting prior subclinical infection. Initial symptomatic treatments were ineffective. Following confirmed pertussis diagnoses, Cases 1 and 2 were treated with compound sulfamethoxazole (800 mg per dose, administered twice daily for a total duration of 5 days), leading to significant symptom alleviation. Case 3 received azithromycin (400 mg on the first day, 200 mg/d on days 2 to 5, with a total course of treatment of 5 days), also resulting in substantial symptom relief. All confirmed cases eventually tested negative for pertussis nucleic acid upon re-examination. This family cluster highlights the diagnostic challenges posed by atypical pertussis in adults and adolescents, emphasizing the need for increased awareness among GPs. Early identification, aggressive family member screening, and appropriate antibiotic therapy (considering local resistance patterns) are crucial for effective management and prevention of further transmission within communities. Strengthening primary care's capacity for recognizing and managing pertussis is paramount to combating its resurgence.