Background: Influenza causes significant morbidity and mortality in the United States. Among patients infected with influenza, the presence of bacterial co-infection is associated with worse clinical outcomes; less is known regarding the clinical importance of viral co-infections. The objective of this study was to determine rates of viral co-infections in emergency department (ED) patients with confirmed influenza and association of co-infection with disease severity.Methods: Secondary analysis of a biorepository and clinical database from a parent study where rapid influenza testing was implemented in four U.S. academic EDs, during the 2014-2015 influenza season. Patients were systematically tested for influenza virus using a validated clinical decision guideline. Demographic and clinical data were extracted from medical records; nasopharyngeal specimens from influenza-positive patients were tested for viral co-infections (ePlex, Genmark Diagnostics). Patterns of viral co-infections were evaluated using chi-square analysis.The association of viral co-infection with hospital admission was assessed using univariate and multivariate regression. Results:The overall influenza A/B positivity rate was 18.1% (1071/5919). Of the 999 samples with ePlex results, the prevalence of viral co-infections was 7.9% (79/999). The most common viral co-infection was rhinovirus/enterovirus (RhV/EV), at 3.9% (39/999). The odds of hospital admission (OR 2.33, 95% CI: 1.01-5.34) increased significantly for those with viral co-infections (other than RhV/EV) versus those with influenza A infection only. Conclusion:Presence of viral co-infection (other than RhV/EV) in ED influenza A/B positive patients was independently associated with increased risk of hospital admission. Further research is needed to determine clinical utility of ED multiplex testing.

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Background The chief or presenting complaint is the reason for seeking health care, often in the patient’s own words. In limited resource settings, a diagnosis-based approach to quantifying burden of disease is not possible, partly due to limited availability of an established lexicon or coding system. Our group worked with colleagues from the African Federation of Emergency Medicine building on the existing literature to create a pilot symptom list representing an attempt to standardize undifferentiated chief complaints in emergency and acute care settings. An ideal list for any setting is one that strikes a balance between ease of use and length, while covering the vast majority of diseases with enough detail to permit epidemiologic surveillance and make informed decisions about resource needs. Methods This study was incorporated as a part of a larger prospective observational study on human immunodeficiency virus testing in Emergency Departments in South Africa. The pilot symptom list was used for chief complaint coding in three Emergency Departments. Data was collected on 3357 patients using paper case report forms. Chief complaint terms were reviewed by two study team members to determine the frequency of concordance between the coded chief complaint term and the selected symptom(s) from the pilot symptom list. Results Overall, 3537 patients’ chief complaints were reviewed, of which 640 were identified as ‘potential mismatches.’ When considering the 191 confirmed mismatches (29.8%), the Delphi process identified 6 (3.1%) false mismatches and 185 (96.9%) true mismatches. Significant chief-complaint clustering was identified with 9 sets of complaints frequently selected together for the same patient. “Pain” was used 2076 times for 58.7% of all patients. A combination of user feedback and expert-panel modified Delphi analysis of mismatched complaints and clustered complaints resulted in several substantial changes to the pilot symptom list. Conclusions This study presented a systematic methodology for calibrating a chief complaint list for the local context. Our revised list removed/reworded symptoms that frequently clustered together or were misinterpreted by health professionals. Recommendations for additions, modifications, and/or deletions from the pilot chief complaint list we believe will improve the functionality of the list in low resource environments.