The Epidemiology of Upper Respiratory Infections at a Tertiary Care Center: Prevalence, Seasonality, and Clinical Symptoms

Improved multiplex PCR detection methods are facilitating the correlation of the etiology of respiratory tract infections with specific symptoms or clinical manifestations. We conducted a retrospective analysis of the incidence of respiratory pathogens and initial symptoms in 1,286 patients at a tertiary care center tested by multiplex respiratory pathogen PCR from July 1, 2012, to June 30, 2013. Rhinovirus/enterovirus (Rhino/Entero) infections were the most prevalent (25.4%) followed by respiratory syncytial virus (RSV) (13.6%) and influenza A (6.2%). Eleven percent of patients were positive for multiple analytes with Rhino/Entero and RSV being the most common combination. Asthma or asthma exacerbation was the most common presenting symptom in patients positive for Rhino/Entero (38.4%) or positive for Rhino/Entero along with RSV or hMPV (34.8%). Of the patients positive for Rhino/Entero and presenting with asthma, 97% were ≤17 years of age. RSV positive patients most commonly presented with respiratory distress (40.3%) followed by asthma (18%) or pneumonia (18%). The most prevalent initial clinical manifestation for influenza was fever (27.4%) followed by respiratory distress (13%) or pneumonia (11.9%). The significant percentage of patients positive for Rhino/Entero virus presenting with asthma supports the role of rhinovirus as an important trigger for asthma exacerbation.