Methods: We conducted an observational study of ARI among otherwise healthy, 0-65y individuals at five US military hospitals. Nasopharyngeal swabs were collected at enrollment and tested by a multiplex respiratory pathogen panel (Diatherix Laboratories, Inc.; Huntsville, AL) targeting 9 viruses (rhinovirus, influenza, adenovirus, coronavirus, coxsackievirus/echovirus, RSV, parainfluenza, human metapneumovirus and bocavirus) and 10 bacteria. Demographics and risk factors were collected at baseline. Symptom severity was recorded over 10 days via patient diary.
Results: Specimens from 898 enrollees (637 adults and 261 children) were evaluated on multiplex PCR respiratory panel. Of these, 315 (35.1%) were negative for a viral pathogens and these subjects represented older, Caucasian population with low likelihood of having young children in the household. In general, both children and adults with unidentified viral etiology had milder symptoms, including less hospitalization among children (p=0.04). However, more moderate/severe diarrhea (13.2% vs. 5.9%, p<0.01) and nausea (28.5% vs. 21.5%, p=0.04) was reported among adults with unidentified viral etiology. In addition, they were more likely to report use of antibiotics (35.6% vs. 24.7%, p<0.01) and to have abnormal chest X-rays if taken (34.4% vs. 13.6%, p=0.02) than those with known viral etiology. Adults with unidentified viral etiology had higher detection of bacterial respiratory pathogens (72.4% vs. 61.1%, overall; p<0.01), including Moraxella catarrhalis, Mycoplasma pneumoniae, and Streptococcus pyogenes.
Conclusion: ARI cases with unidentified viral etiology tended to be older and to have milder symptoms. The possible contribution of bacterial respiratory pathogens to ARI needs further evaluation and may affect management strategies for these patients.
W. J. Chen,
M. Fairchok, None
C. Schofield, None
K. J. St. Clair, None
P. Danaher, None
M. Rajnik, None
E. Mcdonough, None
D. Mor, None
M. Ridore, None
T. Burgess, None
L. Malone, Diatherix Lab: Investigator , Salary
E. Grigorenko, Diatherix lab: Investigator , Salary
D. Stalons, Diatherix: Employee , Salary
E. Millar, None