2627. Dynamics of Respiratory Viral Co-infections: Predisposition for and Clinical Impact of Viral Pairings in Children and Adults

BACKGROUND: The clinical relevance of respiratory viral co-infections is unclear. Few studies determine epidemiology and impact of specific co-infection pairings. Here we assess the dynamics of respiratory viral co-infections, determine any predisposition for specific pairings to occur and evaluate resulting clinical impact on hospitalization. METHODS: We reviewed respiratory viral panel results collected at The Cleveland Clinic between November 2013 to Jun 2018. Monthly prevalences, mono-infections and co-infections of 13 viral pathogens were tabulated. Employing a mathematical model which utilized each individual virus’ co-infection rate and prevalence patterns of concurrent circulating respiratory viruses, we calculated an expected number of occurrences for 132 viral pairing permutations. Expected vs observed co-infection occurrences were compared using binomial tests. For viral pairings occurring at significantly higher prevalence than expected, logistic regression models were used to compare hospitalization between patients with co-infection to ones with mono-infection. RESULTS: Of 30,535 respiratory samples, 9,843 (32.2%) samples were positive for at least 1 virus and 1,018 (10.82%) were co-infected. Co-infections occurred in 18% of pediatric samples and only 3% of adult samples (P < 0.001). Adenovirus C (ADVC had the highest co-infection rate (68.3%) while influenza B had the lowest (10.07%). Using our model, ADVC – rhinovirus (HRV), RSVA - HRV, and RSVB - HRV pairings occurred at significantly higher prevalence than expected (P < 0.05). In children, HRV-RSVB co-infection were significantly less likely to be hospitalized than patients with HRV mono-infections (ORmono/co = 2.3; 95% CI 1.1 to 4.7; P = 0.028). Additionally, HRV - ADVC co-infected children were less likely to be hospitalized than either HRV (OR(mono/co) = 3.3; 95% CI 1.6 to 6.8; P < 0.001) or ADVC (OR(mono/co) = 1.9; 95% CI 1.1 to 3.2; P = 0.024) mono-infected children. Regardless of the infecting virus, children were less likely to be hospitalized than similarly-infected adults. CONCLUSION: Respiratory viral co-infections are largely a pediatric phenomenon. Select viral pairings occur more often than predicted by our model, many of which are associated with altered severity of resultant disease. [Image: see text] [Image: see text] [Image: see text] [Image: see text] DISCLOSURES: All authors: No reported disclosures.