Pneumococcal Bacteraemia in Adults over a 10-year period (2011 - 2020): A Clinical and Serotype Analysis

Clinton Maricano Gregory Colaco; Matthew O'Sullivan; Hayden Zhang; Danica Huynh; Vitali Sintchenko; Shahin Oftadeh; Gwendolyn L Gilbert; Ravindra Dotel

doi:10.1111/imj.16045

Pneumococcal Bacteraemia in Adults over a 10-year period (2011 - 2020): A Clinical and Serotype Analysis

Intern Med J. 2023 Mar 5. doi: 10.1111/imj.16045. Online ahead of print.

Authors

Clinton Maricano Gregory Colaco^{1

2

3}, Matthew O'Sullivan^{4

5

6}, Hayden Zhang¹, Danica Huynh¹, Vitali Sintchenko^{5

7

8}, Shahin Oftadeh⁹, Gwendolyn L Gilbert⁵, Ravindra Dotel¹⁰

Affiliations

¹ Centre for Infectious Diseases and Microbiology, Westmead Hospital, Sydney, New South Wales, Australia.
² The University of Sydney, Westmead Clinical School, Sydney, New South Wales, Australia.
³ Griffith University, School of Medicine and Dentistry.
⁴ Centre for Infectious Diseases and Microbiology Laboratory Services, New South Wales Health Pathology-Institute of Clinical Pathology and Medical Research, Westmead Hospital, Sydney, New South Wales, Australia.
⁵ Sydney Institute for Infectious Diseases, The University of Sydney, Sydney, New South Wales, Australia.
⁶ NSW Health Pathology, Sydney, New South Wales, Australia.
⁷ Centre for Infectious Diseases and Microbiology- Public Health, Westmead Hospital, Sydney, New South Wales, Australia.
⁸ NSW Invasive Pneumococcal Disease Reference Laboratory, Centre for Infectious 13Diseases and Microbiology Laboratory Services, Institute of Clinical Pathology and Medical Research, NSW Health Pathology, Sydney, New South Wales, Australia.
⁹ Centre for Infectious Diseases and Microbiology Laboratory Services, NSW Invasive Pneumococcal Disease Reference Laboratory, Institute of Clinical Pathology and Medical Research, NSW Health Pathology, Sydney, New South Wales, Australia.
¹⁰ Department of Infectious Diseases, Blacktown Hospital, Sydney, NSW, Australia.

PMID: 36872866
DOI: 10.1111/imj.16045

Abstract

Background: Streptococcus pneumoniae (pneumococcus) is a human nasopharyngeal tract coloniser responsible for invasive pneumococcal disease (IPD), which is largely vaccine preventable. Vaccination is recommended from birth for all, and through adulthood for those with risk conditions.

Aims: To describe the clinical and serotype analysis of pneumococcus bacteraemia over a 10-year period.

Methods: A 10-year (Feb 2011 - Dec 2020) retrospective review was performed on all adult (age ≥ 18 years) pneumococcus bacteraemia presenting to the four public hospitals in Western Sydney, Australia. Comorbidities and risk factors were recorded.

Results: Three hundred unique episodes of S pneumoniae bloodstream infection (SPBI) were identified during the study period. The median age for SPBI was 63 years with 31.7% aged 70 years or older. 94.7% had one or more risks factors for SPBI. Pneumonia was reported in 80% of all SBPI, whereas meningitis was reported in 6% and infective endocarditis in <1%. Asplenia was noted in 2.4%. Seven and 30-day mortality was 6.6% and 11.9%, with a higher 30-day mortality in those aged ≥70 years (24.4%). The serotype distribution showed 7-valent conjugate vaccine (7vPCV) covered 11.0% of all isolates, whereas 13-valent conjugate vaccine (13vPCV) and a 23-valent polysaccharide vaccine (23vPPV) covered 41.7% and 69.0% respectively. Immunisation details were available for 110 individuals, of whom, only 7.3% had received pneumococcal vaccination.

Conclusions: Most patients with pneumococcal bacteraemia had age or comorbidity related risk factors but were not vaccinated. Two-thirds of cases occurred in people aged <70 years. 13vPCV and 23vPPV covered 41.7% and 69.0% of bacteraemic isolates. This article is protected by copyright. All rights reserved.

Keywords: Immunization; Pneumococcal Infections; Pneumonia, Pneumococcal; Streptococcus pneumoniae; Vaccines, Conjugate.