In an observational study involving 104 patients, aged 40–85 years, with moderate/severe COPD, testing for pertussis-specific antibodies (anti-PT) revealed that 14 out of 104 (13.5%) patients exhibited anti-PT concentrations ≥50 IU/mL in either year 1 or year 2. This evidence concerns the gene F2 and chronic obstructive pulmonary disease.