What is the appropriate treatment for a 30-year-old male with a 12-day history of intermittent coughing episodes, vomiting, and a whooping sound on inspiration, lacking adult Tdap (tetanus, diphtheria, and pertussis) booster shots?

Treatment of Pertussis in a Healthcare Worker

This patient requires immediate treatment with azithromycin (10 mg/kg on day 1, then 5 mg/kg daily for days 2-5) to eliminate Bordetella pertussis and prevent transmission to vulnerable hospital patients, plus Tdap vaccination and immediate work restriction until 5 days of antibiotics are completed. 1, 2, 3

Immediate Antibiotic Treatment

The clinical presentation—12 days of paroxysmal cough with post-tussive vomiting and inspiratory whooping—is diagnostic of pertussis until proven otherwise. 4 Macrolide antibiotics must be initiated immediately, even though they will not alter the clinical course at this stage (paroxysmal phase), because the primary goal is to render the patient non-infectious and prevent nosocomial transmission. 1, 2, 5

Preferred Antibiotic Regimen

• Azithromycin is the first-line choice: 10 mg/kg (or 500 mg) on day 1, followed by 5 mg/kg (or 250 mg) daily on days 2-5 2, 3, 6
• This regimen achieves 100% bacterial eradication with significantly fewer gastrointestinal side effects (18.8%) compared to erythromycin (41.2%) 6
• Compliance is markedly superior: 90% of patients complete azithromycin versus only 55% completing erythromycin 6

Alternative Regimens

• Clarithromycin: 500 mg twice daily for 7 days (equally effective with better tolerability than 14-day erythromycin) 3, 7
• Erythromycin: 500 mg four times daily for 14 days (traditional regimen, but poorly tolerated) 5, 3
• Trimethoprim-sulfamethoxazole: Alternative for patients who cannot tolerate macrolides 3

Infection Control and Work Restriction

This healthcare worker must be immediately removed from patient care and placed on respiratory droplet precautions. 1, 2 The contagious period in untreated pertussis extends beyond 6 weeks, with peak infectiousness during the first 1-2 weeks (catarrhal phase) and early paroxysmal phase. 1 Attack rates among exposed nonimmune contacts reach 80-90%. 1

• Return to work only after completing 5 days of appropriate antibiotic therapy 1, 2
• Without treatment, the patient remains infectious for over 6 weeks from symptom onset 1

Tdap Vaccination

Administer Tdap vaccine immediately, despite the current infection. 4 The ACIP guidelines explicitly state that adults with a history of pertussis should still receive Tdap because:

• Duration of natural immunity is uncertain (may wane as early as 7 years post-infection) 4
• Diagnosis confirmation can be difficult 4
• No safety concerns exist for vaccinating someone with current or prior pertussis 4
• As a healthcare worker, he requires protection against future exposures 4

The current illness is not a contraindication to Tdap vaccination. 4 However, if he has moderate-to-severe acute illness, defer vaccination until symptoms resolve. 4

Contact Tracing and Prophylaxis

All close contacts (patients, coworkers, household members) must be identified and offered post-exposure prophylaxis within 21 days of exposure. 1, 2 This is critical given his hospital employment and potential exposure of immunocompromised or infant patients.

• Prophylaxis regimen: Same as treatment (azithromycin preferred) 2
• Prioritize household contacts and high-risk individuals (infants, pregnant women, immunocompromised) 1, 2

Clinical Pitfalls to Avoid

• Do not delay antibiotics waiting for culture confirmation—the clinical presentation is sufficient, and cultures are often negative by the paroxysmal phase 4
• Do not withhold antibiotics because "they won't help the cough"—the goal is infection control, not symptom relief 1, 5, 3
• Do not use the 14-day erythromycin regimen unless azithromycin and clarithromycin are unavailable—poor compliance undermines the infection control objective 3, 6
• Do not allow return to work before completing 5 full days of antibiotics, even if symptoms improve 1, 2

Symptomatic Management

While antibiotics eliminate infectiousness, the paroxysmal cough typically persists for weeks regardless of treatment. 4, 3 Inhaled ipratropium may provide modest symptomatic relief. 4 Cough suppressants are generally ineffective for pertussis-related paroxysms. 4