TABLE 3.
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).
| Shelter names | Randomized waves | ||||||
|---|---|---|---|---|---|---|---|
| Nov‐19 | Dec‐19 | Jan‐20 | Feb‐20 | Mar‐20 | Apr‐20 | ||
| O, M, and F | Influenza cases | 6 | 1 | 5 | 1 | 0 | 0 |
| Persons at risk a | 372 | 372 | 372 | 372 | 372 | 372 | |
| B and E | Influenza cases | 1 | 14 | 1 | 0 | 0 | 0 |
| Persons at risk | 170 | 170 | 170 | 170 | 170 | 170 | |
| A and C | Influenza cases | 1 | 0 | 2 | 0 | 0 | 0 |
| Persons at risk | 105 | 105 | 105 | 105 | 105 | 105 | |
| D and L | Influenza cases | 1 | 3 | 13 | 2 | 0 | 0 |
| Persons at risk | 385 | 385 | 385 | 385 | 385 | 385 | |
| Risk ratio | 95% confidence interval | p‐value | |||||
| Influenza virus infection determined by RT‐PCR | 1.73 | 0.50–6.00 | 0.386 | ||||
Note: 
, Standard surveillance; 
, standard surveillance + test‐and‐treat protocol.
Abbreviations: ARI, acute respiratory illness; RT‐PCR, reverse transcription polymerase chain reaction.
a
Persons at risk determined by static measure of maximum nightly shelter capacity.