"Background
...This study aims to urgently evaluate the effects of mRNA COVID-19 vaccination on COVID-19 infection rates and related behaviors among participants of the Yamato Project, which includes employees of Japanese small and medium-sized enterprises (SMEs)...
Results...
Vaccination status and COVID-19 infection
A higher percentage of participants who contracted COVID-19 had received at least one dose of the vaccine (51.3%) compared to those who did not contract the virus (39.0%) (p < 0.001). The odds of contracting COVID-19 were higher among vaccinated individuals compared to unvaccinated individuals...
Impact of number of vaccine doses
... Participants who received one to two doses had an adjusted OR of 1.63 (95% CI: 1.08-2.46, p = 0.020); those who received three to four doses had an adjusted OR of 2.04 (95% CI: 1.35-3.08, p = 0.001); and those who received five to seven doses had an adjusted OR of 2.21 (95% CI: 1.07-4.56, p = 0.033), indicating a higher reported risk of infection with an increasing number of doses ..."
@ Nakatani et al. This is an open access article distributed under the terms of the Creative Commons Attribution License CC-BY 4.0., which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
License
This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.