Dörr et al.: COVID mask study Health care workers (HCWs) shows BLUE surgical masks in Hospital settings far more ineffective & POSITIVE home contact NOT workplace, drives INFECTION (OR 7.79, <0.001)
Risk of infection with POSITIVE home contact, univariate analysis OR 8.82, 95% CI 7.09 - 11.0), multivariate analyses OR 7.79, 95% CI 5.98 - 10.15), bot p< 0.001
In this study, SARS-CoV-2 positivity in HCWs was associated with cumulative COVID-19 patient exposure. The odds of being SARS-CoV-2–positive were reduced by more than 40% in individuals using respirators irrespective of cumulative exposure, even after adjusting for multiple work- and nonwork-related covariables.
For those exposed to patients, positivity was 21% for HCWs using respirator masks and 35% for those using surgical/mixed masks (OR, 0.49; 95% CI, 0.39-0.61), showing an increase for surgical/mixed mask users (OR, 1.21; 95% CI, 1.15-1.28) and respirator mask users (OR, 1.15; 95% CI, 1.05-1.27) across categories of patient exposure (Figure).’
The implication of this post is that all the previous articles/posts claiming masks not helpful and actually harmful are not being contradicted. However, this post describes professional level masking that seems not easily available to the public, will also be much more expensive and counter productive to the argument against masking for it assault on social relationships, especially in young and developing children. Without this analysis the article appears counterproductive. It also implies that masking will be useful and supports the public going backwards in reclaiming its humanity and ability function more freely again. Reporting is really never neutral and to not deal with the contradictions and/or caveats needed it feel just as propagandistic as mainstream media.
I couldn't find in the article where the participants were pre-tested to see if they had antibodies or T-cell immunity from previous infection. Doesn't this create confounding aspects of the study? This is also self reporting which limits accuracy. This amounts to an observational study. Be careful how much you depend on these results to protect you.