Late Breaking Abstract - Seroprevalence of Bordetella pertussis in chronic obstructive pulmonary disease (COPD) patients

Abstract

Background: Pertussis is under-recognised and under-reported in adults and COPD patients. It may play a role in the acute exacerbation of COPD, hence it is necessary to better understand the pertussis burden in these groups and its control.

Aim: We assessed the seroprevalence of B. pertussis in COPD patients aged 40–85 years from the AERIS study (NCT01360398, UK).

Methods: Serological testing for B. pertussis antibodies was performed on sera collected in 2013, by ELISA, for IgG antibodies against pertussis toxoid (anti-PT; shown here) and against filamentous haemagglutinin. Anti-PT IgG antibody titres ≥50 IU/mL indicate exposure, while anti-PT IgG titres ≥70–<120 IU/mL or ≥120 IU/mL indicate recent exposure to B. pertussis within the last 12 or 6 months, respectively.

Results: Overall, among the 87 COPD patients, the geometric mean concentration of anti-PT antibodies was 12.4 IU/mL (95% CI: 9.6–16.1). 12 patients had evidence of exposure, 8 of them had anti-PT IgG titres between 50–<70 IU/mL, 2 had between 70–<120 IU/mL and 2 had titres ≥120 IU/mL. Seroprevalence over the period tested was 12/87 (13.8%), with 4/87 (4.6%) showing recent exposure to B. pertussis. In the 12 pertussis-exposed patients, 32/37 exacerbations tested were associated with <2% blood eosinophils.

Conclusions: This study shows a seroprevalence of pertussis in >13% of COPD patients. During 2009–2018, the reported rates for pertussis diagnoses in the UK Clinical Practice Research Datalink were <11/100,000 person-years follow up in COPD patients. Our results indicate a substantial underdiagnosis of pertussis, warranting improved estimates and evaluation of its impact on COPD outcomes.

Funding: GlaxoSmithKline Biologicals SA