Cet article est une Preprint
Les preprints sont des rapports de recherche préliminaires qui n'ont pas été certifiés par l’évaluation par les pairs. Ils ne devraient pas être considérés comme guidant la pratique clinique ou les comportements liés à la santé et ne devraient pas être rapportés dans les médias comme des informations établies.
Les preprints publiées en ligne permettent aux auteurs de recevoir des commentaires rapidement, et toute la communauté scientifique peut évaluer indépendamment le travail et répondre en conséquence. Ces commentaires sont publiés avec les preprints que quiconque peut lire et servir d’évaluation post-publication.
Predictors of SARS-CoV-2 infection following high-risk exposure (preprint)
medrxiv; 2021.
Preprint
Dans Anglais
| medRxiv | ID: ppzbmed-10.1101.2021.10.20.21265295
ABSTRACT
ABSTRACT Background Non-pharmaceutical interventions (NPIs) are recommended for COVID-19 mitigation. However, the effectiveness of NPIs in preventing SARS-CoV-2 transmission remains poorly quantified. Methods We conducted a test-negative design case-control study enrolling cases (testing positive for SARS-CoV-2) and controls (testing negative) with molecular SARS-CoV-2 diagnostic test results reported to California Department of Public Health between 24 February-26 September, 2021. We used conditional logistic regression to assess predictors of case status among participants who reported contact with an individual known or suspected to have been infected with SARS-CoV-2 (“high-risk exposure”) within ≤14 days of testing. Results 643 of 1280 cases (50.2%) and 204 of 1263 controls (16.2%) reported high-risk exposures ≤14 days before testing. Adjusted odds of case status were 2.94-fold (95% confidence interval 1.66-5.25) higher when high-risk exposures occurred with household members (vs. other contacts), 2.06-fold (1.03-4.21) higher when exposures occurred indoors (vs. not indoors), and 2.58-fold (1.50-4.49) higher when exposures lasted ≥3 hours (vs. shorter durations) among unvaccinated and partially-vaccinated individuals; excess risk associated with such exposures was mitigated among fully-vaccinated individuals. Mask usage by participants or their contacts during high-risk exposures reduced adjusted odds of case status by 48% (8-72%). Adjusted odds of case status were 68% (32-84%) and 77% (59-87%) lower for partially- and fully-vaccinated participants, respectively, than for unvaccinated participants. Benefits of mask usage were greatest when exposures lasted ≥3 hours, occurred indoors, or involved non-household contacts. Conclusions NPIs reduced the likelihood of SARS-CoV-2 infection following high-risk exposure. Vaccine effectiveness was substantial for partially and fully vaccinated persons. KEY POINTS SARS-CoV-2 infection risk was greatest for unvaccinated participants when exposures to known or suspected cases occurred indoors or lasted ≥3 hours. Face mask usage when participants were exposed to a known or suspect case reduced odds of infection by 48%.
Texte intégral:
Disponible
Collection:
Preprints
Base de données:
medRxiv
Sujet Principal:
COVID-19
langue:
Anglais
Année:
2021
Type de document:
Preprint
Documents relatifs à ce sujet
MEDLINE
...
LILACS
LIS