Influenza detection and intervention effect on reducing secondary spread of influenza virus
respiratory illness, infection, ARI, infections
VIRUS INFECTION, INFECTIONS, INFECTION, INFLUENZA A, INFLUENZA
Among all ARI‐participant encounters, 51 (4.0%) influenza virus infections (A = 15; B = 37) were identified through RT‐PCR. Of the influenza A subtypes, A(H1N1)pdm09 predominated (93.3%). Most infections were identified among participants 18–59 years (54.9%; Table Among the 269 ARI encounters that were eligible for the intervention, 21 (7.8%; Table Overall, more infections were identified during intervention periods (n = 32) compared with control periods (n = 19). Restricting analysis to Year 1 of the study, the relative risk of infection during the intervention periods compared with control periods, adjusted for calendar time, was 1.73 (95% confidence interval [CI] 0.50–6.00, p‐value = 0.386; Table Relative risk of infection during the intervention period compared with the control period using a generalized linear mixed model following a Poisson distribution with a log link and robust variance, adjusted for calendar time and an exposure time variable based on shelter capacity. This model includes ARI‐participant encounters from Year 1 of the study (11/15/2019–4/31/2020).
Abbreviations: ARI, acute respiratory illness; RT‐PCR, reverse transcription polymerase chain reaction.Persons at risk determined by static measure of maximum nightly shelter capacity.