2.1 Data collection
The ORegon CHild Absenteeism due to Respiratory Disease Study (ORCHARDS)
is a prospective study of K-12 student absenteeism and acute respiratory
illness (ARI) in a community setting. ORCHARDS is ongoing and has been
described in depth elsewhere.7,8 The study is based in
the Oregon School District, located in Southcentral Wisconsin. The
presence of influenza within the school district is verified through
home visits where research staff record demographic and symptom
information and collect a nasal specimen and an oropharyngeal or a
nasopharyngeal (NP/OP) specimen from eligible students. To participate,
children must be experiencing at least two ARI symptoms that began
within seven days of a parent or guardian calling the study phoneline,
as well as a Jackson score of at least 2.9
Research staff perform a RIDT on the student’s nasal specimen using the
Quidel Sofia® Influenza A + B FIA and notify the family of the result
the same day as specimen collection, usually within 6 hours of the home
visit. The nasal swab is subsequently combined with the NP/OP swab in
viral transport media and shipped via courier to the Wisconsin State Lab
of Hygiene. The combined nasal and NP/OP specimens are tested for
influenza A and B virus and Human RNase P using the CDC Human Influenza
Virus Real‐time RT‐PCR Diagnostic Panel (Cat. # FluIVD03). Student
specimens are also tested for non-influenza respiratory viruses using a
multiplexed PCR respiratory pathogen panel (RPP: Luminex NxTAG
Respiratory Pathogen Panel).
For this analysis, we used data and specimens collected during six
sequential influenza seasons—2014-2015 through 2019-2020. The ORCHARDS
protocol was reviewed and approved by the University of Wisconsin Health
Sciences Institutional Review Board.