Community‐acquired invasive Staphylococcus aureus: Uncovering disparities and the burden of disease in Auckland children

Abstract

Aim Staphylococcus aureus (SA) causes serious invasive disease in children. Large studies have measured the incidence of SA bacteraemia, but there is less information on the total burden of community‐acquired invasive SA (iSA) in children. Methods A retrospective, cross‐sectional analysis of Auckland resident children aged 0–14 years who were hospitalised with iSA between 2011 and 2015 was performed. Laboratory databases and SA‐related international classification of diseases 10 discharge codes were searched to identify community‐onset cases with SA isolated from a normally sterile site. Clinical records and coroner's reports were reviewed to determine clinical syndromes and exclude nosocomial infections. Results A total of 295 children with iSA were identified. The average annual incidence of iSA was 18.6 per 100 000 – for Pacific populations 44.3 per 100 000, Māori 24.3 per 100 000 and New Zealand European and other 8.8 per 100 000; 68% had bacteraemia. The incidence of iSA for Pacific infants was 10 times greater than non‐Māori/non‐Pacific (113.4/100 000 population vs. 11.8/100 000). Multivariate analysis found a higher risk of admission in Pacific children, males and those living in areas of high deprivation. Thirty‐two patients (10.8%) were admitted to the intensive care unit; risk was higher in infants, Pacific children and those with respiratory infection (Relative Risk (RR) 12.2, 95% confidence interval (CI) 5.7–26.4) and multifocal (RR 6.9, 95% CI 3.4–13.8) and endovascular disease (RR 8.9, 95% CI 3.9–20.6). All deaths (n = 7) had respiratory infections, and four were patients <1 year of age. Conclusions Studies investigating SA bacteraemia alone significantly underestimate the total burden of iSA disease. There are marked ethnic and socio‐economic disparities in iSA disease among Auckland children. Pacific infants are at the highest risk.

Surveillance of pediatric parapneumonic effusion/empyema in New Zealand

“…We found equal pediatric empyema cases attributable to S. aureus and S. pneumoniae rather than S. pneumoniae dominance seen elsewhere 2–5 . This could be due to the documented high rate of S. aureus colonisation 41 and invasive S. aureus disease 6 in young children in NZ, with overrepresentation of Māori and Pasifika children 6 . Isolation of S. aureus was more common in children of Māori or Pasifika ethnicity in our study.…”

“…colonisation41 and invasive S. aureus disease6 in young children in NZ, with overrepresentation of Māori and Pasifika children 6. Isolation of S. aureus was more common in children of Māori or Pasifika ethnicity in our study.…”

“…The most common causative organism reported internationally in pediatric empyema is Streptococcus pneumoniae , accounting for 41%–79% of cases 2–5 with Streptococcus pyogenes and Staphylococcus aureus less frequently recorded 2–5 . However, New Zealand (NZ) children have a high burden of S. aureus ‐related disease overall, 6,7 with previous studies identifying S. aureus as a significant cause of complicated pneumonia/parapneumonic effusion/empyema (PPE/E) 8–10 …”

“…2 The most common causative organism reported internationally in pediatric empyema is Streptococcus pneumoniae, accounting for 41%-79% of cases [2][3][4][5] with Streptococcus pyogenes and Staphylococcus aureus less frequently recorded. [2][3][4][5] However, New Zealand (NZ) children have a high burden of S. aureus-related disease overall, 6,7 with previous studies identifying S. aureus as a significant cause of complicated pneumonia/parapneumonic effusion/empyema (PPE/E). [8][9][10] An increase in childhood empyema incidence has recently been reported in developed nations including Australia, the United States (US), the United Kingdom (UK), and other European countries.…”

Prospective surveillance for invasive Staphylococcus aureus and group A Streptococcus infections in a setting with high community burden of scabies and impetigo

“…iSA: 4 (7.7%) iGAS: 1 (6.7%) non-Maori/non-Pacific population (Vogel et al, 2020), and Pacific peop Q5 le had seven-fold higher incidence of iGAS than the European 271 population (Williamson et al, 2015). Similar disparities in the incidence of iSA and iGAS have been described between indigenous and non-indigenous populations in Australia (Norton et al, 2004;Tong et al, 2012).…”