Research Article, J Otol Rhinol Vol: 5 Issue: 1
Analysis of Viral Etiologies in Adults with Symptomatic Upper Respiratory Infections in an Outpatient Setting
|Valeria Silva Merea* and Ashutosh Kacker|
|Department of Otolaryngology – Head and Neck Surgery, Weill Cornell Medicine, New York, USA|
|Corresponding author : Dr. Valeria Silva Merea
Weill-Cornell Medicine, Department of Otolaryngology – Head and Neck Surgery, 1305 York Ave, 5th Floor, New York, NY 10021 USA
Tel: (646) 962-5097
Fax: (646) 962-0030
|Received: October 23, 2015 Accepted: November 23, 2015 Published: November 28, 2015|
|Citation: Silva Merea V, Kacker A (2016) Analysis of Viral Etiologies in Adults with Symptomatic Upper Respiratory Infections in an Outpatient Setting. J Otol Rhinol 5:1. doi:10.4172/2324-8785.1000261|
Background: Community-acquired upper respiratory infections represent a significant source of morbidity and mortality, and viruses are the primary etiologic agent. The purpose of this study was to determine the frequency and type of viruses causing severe symptomatic upper respiratory infections in adults presenting to an academic ENT office.
Methods: Retrospective chart review of 37 patients who had a total of 40 respiratory nasopharyngeal samples for viral PCR analysis collected between October 2013 and October 2014.
Results: Viruses were detected in 47.5% (19/40) of samples from 37 patients. The most common viruses isolated as single infections were coronavirus, influenza (A and B) and rhinovirus which were each found in 5 (12.5%) samples. Overall, both coronavirus and influenza were found in 7 (17.5%) studies each vs. 6 (15%) for rhinovirus. Co-infections were detected in 3 (7.5%) cases, either as coronavirus and influenza B (2/3) or parainfluenza and rhinovirus (1/3). Most positive tests occurred in February and March with 5 (12.5%) tests each.
Conclusions: The most frequently detected viruses in adults with severe URI symptoms were coronavirus and influenza, followed closely by rhinovirus. Infections were most commonly detected in the wintertime. Viral PCR testing can be an important tool to guide treatment.
Keywords: Respiratory tract infections; Retrospective study; Coronavirus;Rhinovirus; Influenza; Viral PCR analysis
|Respiratory tract infections; Retrospective study; Coronavirus; Rhinovirus; Influenza; Viral PCR analysis|
|Community-acquired acute respiratory infections represent a significant source of morbidity and mortality, and viruses are thought to be the primary etiologic agent. These infections are frequently selflimited, but they can impose a substantial burden on communities, as they can lead to lost days of work, increases in medical costs, severe illness and in some cases, death. A study that looked into the annual economic burden of influenza epidemics alone in the US, found the projected burden to be $87.1 billion  Common symptoms among patients with acute respiratory illness include cough, myalgia, nasal congestion, headache, sore throat, and rhinorrhea, among others.|
|The goal of this study was to characterize the frequency and type of viral agents causing severe symptomatic upper respiratory infections in adults presenting over a period of one year to an ENT office in an academic center in NYC.|
|Records of all laboratory studies sent by the senior author between October 1st, 2013 and October 12th, 2014 were reviewed for identification of all respiratory viral panel studies performed during this period. In his office, nasopharyngeal samples for viral analysis are only obtained for patients who present with severe URI symptoms including fevers and/or myalgias. Subsequently, the charts of all patients who had respiratory viral panel testing were retrospectively reviewed for documentation of demographic information including age and gender, as well as symptomatology at presentation, and for results of the viral polymerase chain reaction (PCR) studies. The only exclusion criterion was age younger than 18.|
|The comprehensive respiratory viral pathogen panel at our institution includes testing for the following viruses: adenovirus, coronavirus, human metapneumovirus, rhinovirus/enterovirus, influenza A and B, respiratory syncytial virus (RSV), and parainfluenza. Specimens were collected with a nasopharyngeal swab (BD Universal Viral Transport kit), with results within 2-4 hrs.|
|This study was approved by the Institutional Review Board at Weill Cornell Medicine.|
|Forty-one respiratory viral panel studies were sent from 38 symptomatic patients for PCR analysis between October 1st 2013 and October 12th 2014, but one patient was excluded due to young age. Thus, 40 viral PCR studies from 37 symptomatic adult patients were included in this study. Patients’ age ranged from 18 to 84 years (median 51), and 54% of patients were female.|
|In order for the viral panel to be obtained, patient must have severe constitutional symptoms including fevers and/or myalgias. Other common accompanying reported symptoms were nasal congestion, rhinorrhea, sore throat, cough, among others, but documentation was somewhat inconsistent.|
|Viruses were detected in 47.5% (19/40) of samples. The distribution of the total number of tests and the positive studies are shown in Figure 1. Most positive tests occurred in February and March with 5 (12.5%) tests each. The most common viruses isolated as single infections were coronavirus, influenza (A and B) and rhinovirus which were each found in 5 (12.5%) samples. Overall, taking into account single and co-infections, however, both coronavirus and influenza were found in 7 (17.5%) studies each vs. 6 (15%) for rhinovirus. Detected coronavirus subtypes included HKU1 (2), NL63 (3), and 229E (2). Influenza B was singly detected in 3 (7.5%) tests, followed by influenza A with 2 (5%), RSV with 1 (2.5%). Co-infections were detected in 3 (7.5%) cases, either as coronavirus and influenza B (2/3) or parainfluenza and rhinovirus (1/3). Figure 2 depicts the etiologic distribution as percentages of all positive viral studies.|
|Figure 1: Monthly distribution of positive and total viral PCR studies performed.|
|Figure 2: Percentage distribution of positive tests.|
|With regards to the monthly distribution by etiologic agent, influenza virus was seen between February and April, with the highest frequency in March. Coronavirus was found in positive samples from January through April, with most positive tests obtained in February. Rhinovirus had the broadest distribution of the top 3 viral etiologies. It was detected in September – October, December – January, and April. Figure 3 displays the monthly distribution of samples positive for coronavirus, rhinovirus and influenza (A and B shown separately).|
|Figure 3: Monthly distribution of samples positive for coronavirus, rhinovirus and influenza (types A and B shown separately).|
|Our study uniquely focuses on an academic ENT office, and it is important to emphasize that in our office, the nasopharyngeal samples for respiratory viral panels were only obtained in patients with severe constitutional symptoms, which included fever or myalgias. Other studies have focused on a primary care or emergency room setting with varying degrees of symptom severity.|
|Influenza and coronavirus were the most common pathogens in our study. Influenza was seen between February and April, while coronavirus prevailed from January through March, both distributions being consistent with previous studies [2,3]. Rhinovirus infection has been shown to have seasonality, with highest incidence in the fall and spring,  also seen in this study. Our frequency of RSV was lower than what other studies have shown [4,5]. No samples were positive for adenovirus or human metapneumovirus. Human metapneumovirus has been shown to be the cause of both upper and lower respiratory tract infections in infants, young children, the elderly, and the immunocompromised populations , which were not well represented (or at all in the case of children) in this sample. In general, there may be geographic and population variations in the frequency of different viruses.|
|Other than influenza, there are no respiratory viruses for which an effective and safe antiviral medication is available. Viral PCR testing’s rapid results allowed for prompt determination of whether a patient would benefit from antiviral therapy, and treatment with a neuraminidase inhibitor could be instituted rapidly if appropriate. Patients with severe constitutional symptoms and a negative viral panel may benefit from antibiotic therapy.|
|One of the limitations of this study is its retrospective nature and its relatively small sample size. In addition, lack of standardization in the documentation of patient’s symptoms prevents us from drawing any conclusions regarding virus-specific symptomatology. Our rationale for using retrospective data was to do a survey of our past experience. In the future, a prospective study looking at this patient population would benefit from a standardized questionnaire given to patients with URI symptoms to report their specific symptoms and their duration at the time of their visit.|
|The most common viral pathogens detected in adults with severe URI symptoms presenting to an academic ENT office were coronavirus and influenza virus, closely followed by rhinovirus. Viral infections were most commonly detected in the winter season, during which most of the symptomatic patients presented. Viral PCR is a rapid means to identify patients who would benefit from antiviral treatment, and allows for its prompt initiation. ENT providers should be aware of viral etiologies other than influenza causing severe URI symptoms, so that treatment is appropriately instituted.|