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Predictors of pandemic influenza infection in adults presenting to two urban emergency departments, Toronto, 2009

Published online by Cambridge University Press:  11 May 2015

Todd C. Lee*
Affiliation:
Division of Infectious Diseases, University of Toronto, Toronto, ON
Linda R. Taggart
Affiliation:
Division of Infectious Diseases, University of Toronto, Toronto, ON
Barbara Mater
Affiliation:
North York General Hospital, Toronto, ON
Kevin Katz
Affiliation:
Division of Infectious Diseases, University of Toronto, Toronto, ON North York General Hospital, Toronto, ON
Allison McGeer
Affiliation:
Division of Infectious Diseases, University of Toronto, Toronto, ON Department of Microbiology, Mount Sinai Hospital, Toronto, ON
*
600 University Avenue, Room 1485, Toronto, ON M5G 1X5; todd.lee@utoronto.ca

Abstract

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Objective:

Identifying features that differentiate patients with H1N1 influenza infection from those with other conditions may assist clinical decision making during waves of pandemic influenza activity.

Methods:

From April 27 to June 15, 2009, nasopharyngeal swabs were obtained from all adults presenting to two urban emergency departments (EDs) with illness including fever or respiratory symptoms. H1N1 infection was detected by reverse transcriptase–polymerase chain reaction. Chart review was performed to compare cases of H1N1 influenza (n = 117) to matched controls.

Results:

The median age of cases was 35 years versus 50 years for controls (p < .001). In those with pre-existing conditions, asthma was present in 31% of cases versus 14% of controls (OR 2.6, 95% CI 1.3–5.4). Cough (OR 7.8, 95% CI 3.2–19), fever (OR 3.0, 95% CI 1.7–5.4), headache (OR 2.0, 95% CI 1.2–3.2), and myalgias (OR 1.9, 95% CI 1.2–3.1) were significantly more common in H1N1 cases. The median white blood cell count was 5.7 × 109/mL versus 10.9 × 109/mL (p < .001). The combination of fever and cough had an OR of 5.3. Fever, cough, low white blood cell (WBC) count, and tachycardia had the highest OR at 11. The absence of both fever and cough had a negative predictive value of 99%, but this occurred in only 8% of controls.

Conclusion:

In patients presenting to the ED, the combination of fever, cough, tachycardia, and WBC count < 10 × 109/mL was suggestive of H1N1 influenza infection. However, clinical features could not reliably distinguish influenza from other acute respiratory illnesses in adult ED patients.

Type
Original Research • Recherche originale
Copyright
Copyright © Canadian Association of Emergency Physicians 2011

References

1.Novel Swine-Origin Influenza A (H1N1) Virus Investigation Team, Dawood, FS, Jain, S, Finelli, L, et al. Emergence of a novel swine-origin influenza A (H1N1) virus in humans. N Engl J Med 2009;360:2605–15.Google ScholarPubMed
2.Monmany, J, Rabella, N, Margall, N, et al. Unmasking influenza virus infection in patients attended to in the emergency department. Infection 2004;32:8997.CrossRefGoogle ScholarPubMed
3.Babcock, HM, Merz, LR, Dubberke, ER, et al. Case-control study of clinical features of influenza in hospitalized patients. Infect Control Hosp Epidemiol 2008;29:921–6.CrossRefGoogle ScholarPubMed
4.D’Heilly, SJ, Janoff, EN, Nichol, P, et al. Rapid diagnosis of influenza infection in older adults: influence on clinical care in a routine clinical setting. J Clin Virol 2008;42:124–8.CrossRefGoogle Scholar
5.van den Dool, C, Hak, E, Wallinga, J, et al. Symptoms of influenza virus infection in hospitalized patients. Infect Control Hosp Epidemiol 2008;29:314–9.CrossRefGoogle ScholarPubMed
6.Babcock, HM, Merz, LR, Fraser, VJ. Is influenza an influenzalike illness? Clinical presentation of influenza in hospitalized patients. Infect Control Hosp Epidemiol 2006;27:266–70.CrossRefGoogle Scholar
7.Call, SA, Vollenweider, MA, Hornung, CA, et al. Does this patient have influenza? JAMA 2005;293:987–97.CrossRefGoogle ScholarPubMed
8.Navarro-Mari, JM, Perez-Ruiz, M, Cantudo-Munoz, P, et al. Influenza-like illness criteria were poorly related to laboratory-confirmed influenza in a sentinel surveillance study. J Clin Epidemiol 2005;58:275–9.CrossRefGoogle Scholar
9.Ebell, MH, White, LL, Casault, T. A systematic review of the history and physical examination to diagnose influenza. J Am Board Fam Pract 2004;17:15.CrossRefGoogle ScholarPubMed
10.Thursky, K, Cordova, SP, Smith, D, et al. Working towards a simple case definition for influenza surveillance. J Clin Virol 2003;27:170–9.CrossRefGoogle ScholarPubMed
11.Walsh, EE, Cox, C, Falsey, AR. Clinical features of influenza A virus infection in older hospitalized persons. J Am Geriatr Soc 2002;50:1498–503.CrossRefGoogle ScholarPubMed
12.van Elden, LJ, van Essen, GA, Boucher, CA, et al. Clinical diagnosis of influenza virus infection: evaluation of diagnostic tools in general practice. Br J Gen Pract 2001;51: 630–4.Google ScholarPubMed
13.Zambon, M, Hays, J, Webster, A, et al. Diagnosis of influenza in the community: relationship of clinical diagnosis to confirmed virological, serologic, or molecular detection of influenza. Arch Intern Med 2001;161:2116–22.CrossRefGoogle ScholarPubMed
14.Monto, AS, Gravenstein, S, Elliott, M, et al. Clinical signs and symptoms predicting influenza infection. Arch Intern Med 2000;160:3243–7.CrossRefGoogle ScholarPubMed
15.Govaert, TM, Dinant, GJ, Aretz, K, et al. The predictive value of influenza symptomatology in elderly people. Fam Pract 1998;15:1622.CrossRefGoogle ScholarPubMed
16.Price, DA, Postlethwaite, RJ, Longson, M. Influenzavirus A2 infections presenting with febrile convulsions and gastrointestinal symptoms in young children. Clin Pediatr (Phila) 1976;15:361–7.CrossRefGoogle ScholarPubMed
17.Boivin, G, Hardy, I, Tellier, G, et al. Predicting influenza infections during epidemics with use of a clinical case definition. Clin Infect Dis 2000;31:1166–9.CrossRefGoogle ScholarPubMed
18.Azevedo, AM, Durigon, EL, Okasima, V, et al. Detection of influenza, parainfluenza, adenovirus and respiratory syncytial virus during asthma attacks in children older than 2 years old. Allergol Immunopathol (Madr) 2003;31:311–7.CrossRefGoogle ScholarPubMed
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