Viruses causing lower respiratory symptoms in young children: findings from the ORChID birth cohort

Sarna, Mohinder; Lambert, Stephen B; Sloots, Theo P; Whiley, David M; Alsaleh, Asma; Mhango, Lebogang; Bialasiewicz, Seweryn; Wang, David; Nissen, Michael D; Grimwood, Keith; Ware, Robert S

Of 8202 swabs, 3894 (47.5%) were taken during symptomatic periods and 4308 (52.5%) from asymptomatic periods. Of all swabs taken any time during symptomatic periods, 1903/3894 (48.9%) were positive for a virus, and 1120/3894 (28.8%) were new VDEs. Overall, 984/4308 (22.8%) swabs taken during asymptomatic periods were positive for a virus, of which 562 (57.1%) were new VDEs and 491/562 (87.4%) were new single virus detections (tables 3 and 4). Table 3 shows that for new VDEs involving only single viruses, HRV-A, HRV-C, IFV-A, PIV-3, RSV-A, RSV-B, HCoV-OC43, HCoV-NL63, HMPV, and AdV had statistically significant, positive AFE values, indicating they were significantly more often associated with ARI episodes than asymptomatic periods. In Table 4 Lower respiratory tract infections and asymptomatic single new virus detections, risk ratios and attributable fractions by respiratory virus in 151 children from the ORChID birth cohort (n=5267 swabs) Continued contrast, HCoV-229E, HCoV-HKU1, WU-PyV, KI-PyV, and HBoV-1 were frequently detected in asymptomatic periods and had low point estimates for AFE, indicating they were less likely to have caused the ARI. Of the total 1641 ARIs, 111 (6.8%) did not have swabs submitted during the ARI episode, including swabs taken 7 days before or 7 days after the last day of the illness. Of the remaining 1530 ARIs, 1154 (75.4%) ARIs (935 (81%) URTI, 219 (19.0%) LRTI) had ≥1 swabs with a virus detected during this period.