A recent study, led by the Canadian Immunization Monitoring Program ACTive (IMPACT) Network, has provided critical insights into the clinical course and risk factors associated with bloodstream infections in children hospitalized for influenza, commonly known as the flu. Bloodstream infections occur when a microorganism enters a host’s bloodstream and triggers an immune response. Both the flu and these secondary infections can lead to sepsis, which occurs when a child’s immune system loses its ability to regulate itself, leading to organ failure and even death. Understanding the factors associated with bloodstream infections in children hospitalized with the flu is crucial for improving patient care and outcomes for these children.
What did the study find?
The study, which analyzed data from over 9,000 laboratory-confirmed flu admissions, found that 87 children (1%) had at least one bloodstream infection caused by bacteria or yeast. The most frequently identified pathogens causing bloodstream infection were Streptococcus pyogenes, Staphylococcus aureus, and Streptococcus pneumoniae. Cancer was the only chronic comorbidity associated with an increased risk of a bloodstream infection, whereas children with chronic lung disorders were less likely to experience a bloodstream infection. Children with laboratory-confirmed non-bloodstream bacterial infection or radiographically-confirmed pneumonia were also more likely to experience a bloodstream infection. Children with bloodstream infections experienced more severe illness, requiring intensive care admission, mechanical ventilation, longer hospital stays, and an increased risk of death compared to those without bloodstream infections. However, this study did not demonstrate whether the increase in disease severity was directly caused by the bloodstream infection or as a result of a more severe influenza illness which increased the risk of secondary infection. In the study, the researchers were unable to clearly differentiate between community or hospital-acquired bloodstream infections.
What is the significance of these findings?
The study's findings provide information for healthcare professionals to help with determining in which cases collecting blood cultures among children hospitalized for the flu could be most beneficial. It also underscores the importance of vaccination against agents that frequently cause bloodstream infections as a preventive measure against severe illness, hospitalization, and death. In particular, receiving pneumococcal vaccines, or vaccines against other bacteria that can cause pneumonia, meningitis, and sepsis, can play a vital role in this regard.
This work highlights how bloodstream infections and sepsis worsen outcomes for children with influenza and the importance of prevention through vaccination in reducing these poor outcomes among children.
- Dr. Manish Sadarangani
About the author
Dr. Manish Sadarangani is an Associate Professor in the Department of Pediatrics at the University of British Columbia. He is the Director of the Vaccine Evaluation Centre at BC Children’s Hospital Research Institute and a co-principal investigator of the IMPACT Network. Dr. Sadarangani is also a member of the Action on Sepsis Research Cluster’s Steering Committee. His work combines clinical trials with basic science to better understand the potential that immunization has in preventing or managing various viral and bacterial diseases. Any infection can lead to the onset of sepsis in patients without appropriate clinical intervention and prevention through vaccination is a critical step to reducing its global burden.