997 Comparison of morbidity and mortality of rhinovirus infection to 2009 pandemic H1N1 influenza A at an academic tertiary referral center

Sunday, March 21, 2010
Grand Hall (Hyatt Regency Atlanta)
Colleen S. Kraft, MD , Emory University, Atlanta, GA
Jesse T. Jacob, MD , Emory University, Atlanta, GA
Marti H. Sears, BSN , Emory University, Atlanta, GA
Nabila Sharifi , Emory University, Atlanta, GA
G. Marshall Lyon, MD, MMSc , Emory University, Atlanta, GA
Eileen M. Burd, PhD , Emory University, Atlanta, GA
Angela M. Caliendo, MD, PhD , Emory University, Atlanta, GA

Background: Viruses other than influenza A can present as an influenza-like illness (ILI) (fever >37.8C and cough/sore throat).  Molecular testing has made feasible the diagnosis of common respiratory viruses.  This is important in tertiary referral centers that treat immunocompromised patients. 

Objective: To compare the morbidity and mortality of rhinovirus infection to influenza A among patients served in a tertiary referral center.

Methods: Retrospective chart review of patients with a positive respiratory viral test result by xTAG® RVP (Luminex Corp, Austin, TX) from 9/9/09 until 10/9/09.  The Mantel-Haenszel chi-square test (categoric variables) and the Wilcoxon rank sum test (continuous variables) were used for comparisons.   

Results: Six-hundred and thirty specimens were received for respiratory viral testing.  There were 128 (20%) positive tests for influenza A, 81 (13%) for rhinovirus, and 11 (1.7%) other viruses.  There were 201 (91%) adults and 19 (9%) children (<18y).  The mean age for the influenza group was lower compared to the rhinovirus group (Table 1).  Gender and race were similar in the 2 groups.  More antiviral treatment was given to the influenza group (p<0.001) but there was no difference in the receipt of antibacterial agents.  More fever and ILI criteria were met in the influenza group than the rhinovirus group (p<0.001).  While there was no difference in underlying comorbidities between the groups, more individuals were immunocompromised (transplant, HIV, actively treated malignancy) in the rhinovirus group (p<0.001).  There were more bacterial or fungal co-infections in the rhinovirus group as compared to the influenza group (p=0.01).  Hospital admission rates between the groups were not significantly different, nor were admissions to the ICU.  Mortality rates were similar in both groups. 

Conclusions: Patients with 2009 pandemic H1N1 influenza A and rhinovirus had similar hospitalization rates and admissions to the ICU.  There were more immunocompromised patients and bacterial co-infections in the rhinovirus group, which could account for the similarity of the clinical course to influenza.  Rhinovirus infection, while usually mild, in a tertiary referral center demonstrates morbidity and mortality similar to influenza A.    

Table 1.


Influenza group

number (%)

Rhinovirus group

number (%)

P value






34.2 y ± 16.8 y

41.2 y ± 15.4 y



97 (76%)

32 (42%)


ILI criteria met

76 (59%)

14 (18%)


Antiviral therapy

58 (45%)

11 (14%)



33 (26%)

23 (30%)



10 (7.8%)

17 (22%)



11 (8.6%)

17 (21%)


Hospital admission

38 (30%)

24 (31%)


ICU stay

7 (5.5%)

7 (9.1%)



2 (1.6%)

2 (2.6%)


NS=not significant