CDC study showed a reduced risk of reinfection with SARS-CoV-2 after covid-19 vaccination.

Reduced Risk of Reinfection with SARS-CoV-2 After COVID-19 Vaccination — Kentucky, May–June 2021 – CDC Morbidity and Mortality Weekly Report

Commentaries on Twitter

This is non randomized. The two biases are:

1. Behavior among those who got vaccinated likely different than those who don't

2. Likely those who didn't tested more aggressively

I would not cite this as many are doinghttps://t.co/rSkBC37uq0

— Vinay Prasad MD MPH (@VPrasadMDMPH) August 7, 2021

Study shows that full #COVIDVaccination ⬇️ likelihood of being re-infected with #COVID19 compared to those who were previously had COVID but were not vaccinated (risk ⬆️ 2.3 fold)#GetVaccinated even if you have had COVID previouslyhttps://t.co/3dF3XPxwYp

@fascinatorfun pic.twitter.com/ip6zTvNN86

— Prof Kamlesh Khunti (@kamleshkhunti) August 7, 2021