Comparing respiratory virus burden among infants across emergency care and in-patient settings

Abstract

Respiratory virus infections are leading causes of admission for infants <1y age; however, the burden among children discharged from emergency care (EC) is not well described. The Southern Hemisphere Influenza and Vaccine Effectiveness Research and Surveillance project, a prospective, population-based respiratory virus surveillance in Auckland New Zealand, provided the opportunity to study these infants.

During the 2014-2015 winter seasons, patients under 1 year old presenting with respiratory symptoms at the Kidz First Children's Hospital had respiratory samples tested for influenza, RSV and Rhinoviruses using real time PCR assays. Rates of visits and patient characteristics were compared between settings.

Virus positivity was high in both settings (Table). Admission rates were higher for those identified as RSV positive, Maori/Pacific Islander, from lower SES areas, <6months and female. In both the EC and admitted patients influenza positivity was higher for older infants. Among those with influenza, admission was higher for children <6 months of age (OR=2.7, 9%%CI: 1.3-5.5) and females (OR=2.8, 95%CI: 1.4-5.6). For RSV, Maori/Pacific Islanders (OR=2.4, 95%CI: 1.2-5.0) and females (OR=2.3, 95%CI: 1.4-4.1) were associated with admission.The socioeconomic gradient was striking with 166 RV admissions per 100,000 children for highest income areas compared to 4415 per 100,000 children in the lowest.

Infants seen in Emergency care have a significant respiratory virus burden with females Maori, Pacific, disadvantaged, RSV positive and <6 months most affected.