Hostname: page-component-89b8bd64d-nlwjb Total loading time: 0 Render date: 2026-05-11T05:39:57.408Z Has data issue: false hasContentIssue false

Identification, Management, and Clinical Characteristics of Hospitalized Patients with Influenza-Like Illness during the 2009 H1N1 Influenza Pandemic, Cook County, Illinois

Published online by Cambridge University Press:  02 January 2015

Kristen E. Metzger
Affiliation:
Chicago Department of Public Health, Chicago, Illinois
Stephanie R. Black
Affiliation:
Chicago Department of Public Health, Chicago, Illinois
Roderick C. Jones
Affiliation:
Chicago Department of Public Health, Chicago, Illinois
Shaun R. Nelson
Affiliation:
Cook County Department of Public Health, Oak Forest, Illinois
Ari Robicsek
Affiliation:
NorthShore University Health System, Evanston, Illinois
Gordon M. Trenholme
Affiliation:
Rush University Medical Center, Chicago, Illinois
Mary Alice Lavin
Affiliation:
Rush University Medical Center, Chicago, Illinois
Stephen G. Weber
Affiliation:
University of Chicago Medical Center, Chicago, Illinois
Sylvia Garcia-Houchins
Affiliation:
University of Chicago Medical Center, Chicago, Illinois
Emily Landon
Affiliation:
University of Chicago Medical Center, Chicago, Illinois
Jorge P. Parada
Affiliation:
Loyola University Medical Center, Maywood, Illinois
Susan I. Gerber*
Affiliation:
Cook County Department of Public Health, Oak Forest, Illinois
*
15900 S. Cicero Avenue, Building E, 3rd Floor, Oak Forest, IL 60452 (sgerber@ccdph.net)

Abstract

Objective.

To describe the identification, management, and clinical characteristics of hospitalized patients with influenza-like illness (ILI) during the peak period of activity of the 2009 pandemic strain of influenza A virus subtype H1N1 (2009 H1N1).

Design.

Retrospective review of electronic medical records.

Patients and Setting.

Hospitalized patients who presented to the emergency department during the period October 18 through November 14, 2009, at 4 hospitals in Cook County, Illinois, with the capacity to perform real-time reverse-transcriptase polymerase chain reaction testing for influenza.

Methods.

Vital signs and notes recorded within 1 calendar day after emergency department arrival were reviewed for signs and symptoms consistent with ILI. Cases of ILI were classified as recognized by healthcare providers if an influenza test was performed or if influenza was mentioned as a possible diagnosis in the physician notes. Logistic regression was used to determine the patient attributes and symptoms that were associated with ILI recognition and with influenza infection.

Results.

We identified 460 ILI case patients, of whom 412 (90%) had ILI recognized by healthcare providers, 389 (85%) were placed under airborne or droplet isolation precautions, and 243 (53%) were treated with antiviral medication. Of 401 ILI case patients tested for influenza, 91 (23%) had a positive result. Fourteen (3%) ILI case patients and none of the case patients who tested positive for influenza had sore throat in the absence of cough.

Conclusions.

Healthcare providers identified a high proportion of hospitalized ILI case patients. Further improvements in disease detection can be made through the use of advanced electronic health records and efficient diagnostic tests. Future studies should evaluate the inclusion of sore throat in the ILI case definition.

Information

Type
Original Articles
Copyright
Copyright © The Society for Healthcare Epidemiology of America 2011

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

Article purchase

Temporarily unavailable