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Multicenter Study
. 2017 Mar 22;17(1):222.
doi: 10.1186/s12879-017-2299-7.

Influenza and respiratory syncytial virus in infants study (IRIS) of hospitalized and non-ill infants aged <1 year in four countries: study design and methods

Mark G Thompson  1   2 , Danielle R Hunt  3 , Ali K Arbaji  4 , Artan Simaku  5 , Veronica L Tallo  6 , Holly M Biggs  7 , Carolyn Kulb  3 , Aubree Gordon  8 , Ilham Abu Khader  4 , Silvia Bino  5 , Marilla G Lucero  6 , Eduardo Azziz-Baumgartner  9 , Pat Shifflett  3 , Felix Sanchez  10 , Basima I Marar  11 , Ilirjana Bakalli  12 , Eric A F Simões  13   14 , Min Z Levine  9 , Jennifer K Meece  15 , Angel Balmaseda  16 , Tareq M Al-Sanouri  4 , Majlinda Dhimolea  17 , Joanne N de Jesus  6 , Natalie J Thornburg  7 , Susan I Gerber  7 , Lionel Gresh  18 ; IRIS Network
Collaborators, Affiliations
Multicenter Study

Influenza and respiratory syncytial virus in infants study (IRIS) of hospitalized and non-ill infants aged <1 year in four countries: study design and methods

Mark G Thompson et al. BMC Infect Dis. .

Abstract

Background: This multi-country prospective study of infants aged <1 year aims to assess the frequency of influenza virus and respiratory syncytial virus (RSV) infections associated with hospitalizations, to describe clinical features and antibody response to infection, and to examine predictors of very severe disease requiring intensive care.

Methods/design: We are enrolling a hospital-based cohort and a sample of non-ill infants in four countries (Albania, Jordan, Nicaragua, and the Philippines) using a common protocol. We are currently starting year 2 of a 2- to 3-year study and will enroll approximately 3,000 infants hospitalized for any acute illness (respiratory or non-respiratory) during periods of local influenza and/or RSV circulation. After informed consent and within 24 h of admission, we collect blood and respiratory specimens and conduct an interview to assess socio-demographic characteristics, medical history, and symptoms of acute illness (onset ≤10 days). Vital signs, interventions, and medications are documented daily through medical record abstraction. A follow-up health assessment and collection of convalescent blood occurs 3-5 weeks after enrollment. Influenza and RSV infection is confirmed by singleplex real time reverse transcriptase polymerase chain reaction (rRT-PCR) assays. Serologic conversion will be assessed comparing acute and convalescent sera using hemagglutination inhibition assay for influenza antibodies and enzyme-linked immunosorbent assay (ELISA) for RSV. Concurrent with hospital-based enrollment, respiratory specimens are also being collected (and tested by rRT-PCR) from approximately 1,400 non-ill infants aged <1 year during routine medical or preventive care.

Discussion: The Influenza and RSV in Infants Study (IRIS) promises to expand our knowledge of the frequency, clinical features, and antibody profiles of serious influenza and RSV disease among infants aged <1 year, quantify the proportion of infections that may be missed by traditional surveillance, and inform decisions about the potential value of existing and new vaccines and other prevention and treatment strategies.

Keywords: Burden; Hospital; Infant; Influenza; Respiratory syncytial virus; Serology.

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Figures

Fig. 1
Fig. 1
Steps in Hospital Enrollment and Follow-up
See this image and copyright information in PMC

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