Clinical Impact of Mixed Respiratory Viral Infection in Children with Adenoviral Infection

Lee, Hyun Jun; Seo, Young Eun; Han, Seung Beom; Jeong, Dae Chul; Kang, Jin Han

Respiratory viral coinfections have been identified in 1.8% -49.2% of respiratory tract infections in previous studies [12, 14, 20, 27, 28] . The variability in the reported coinfection frequency could be due to the methods of viral detection, the number of detectable viruses, the characteristics of enrolled patients, the frequencies of underlying disorders, the seasons when the studies were performed, and the inclusion or exclusion of URTI [14, 28] . Most studies reported a higher frequency of respiratory viral coinfection in younger children than in older children and adults [12, 14, 27, 28] . This presumably was caused by immature immune systems, the lack of protective immunity arising from prior exposures to viruses, and prolonged excretion of respiratory viruses in younger children compared with older children and adults [14, 21, 28] . Although respiratory viral coinfection increased the rate and duration of hospitalization [14, 17, 27] , it eventually did not cause a poorer prognosis such as oxygen supplementation [17, 27] . In a recent meta-analysis, the overall effect of respiratory viral coinfections on the disease severity and prognosis was not significant [15] .