According to a study published by the New England Journal of Medicine, previous Covid infection provides better protection from the Omicron variant than anti-Covid vaccines.

This study, carried out in Qatar from December 2021 to February 2022 [1], corroborates the one carried out in Israel from August to September 2021 [2].

[1"Effects of Previous Infection and Vaccination on Symptomatic Omicron Infections", Heba N. Altarawneh, M.D., Hiam Chemaitelly, Ph.D., Houssein H. Ayoub, Ph.D., Patrick Tang, M.D., Ph.D., Mohammad R. Hasan, Ph.D., Hadi M. Yassine, Ph.D., Hebah A. Al-Khatib, Ph.D., Maria K. Smatti, M.Sc., Peter Coyle, M.D., Zaina Al-Kanaani, Ph.D., Einas Al-Kuwari, M.D., Andrew Jeremijenko, M.D., Anvar H. Kaleeckal, M.Sc., Ali N. Latif, M.D., Riyazuddin M. Shaik, M.Sc., Hanan F. Abdul-Rahim, Ph.D., Gheyath K. Nasrallah, Ph.D., Mohamed G. Al-Kuwari, M.D., Adeel A. Butt, M.B., B.S., Hamad E. Al-Romaihi, M.D., Mohamed H. Al-Thani, M.D., Abdullatif Al-Khal, M.D., Roberto Bertollini, M.D., M.P.H., and Laith J. Abu-Raddad, Ph.D., New England Journal of Medicine, June 15. 2022.

[2"Protection and Waning of Natural and Hybrid Immunity to SARS-CoV-2", Yair Goldberg, Ph.D., Micha Mandel, Ph.D., Yinon M. Bar-On, M.Sc., Omri Bodenheimer, M.Sc., Laurence S. Freedman, Ph.D., Nachman Ash, M.D., Sharon Alroy-Preis, M.D., Amit Huppert, Ph.D., and Ron Milo, Ph.D., New England Journal of Medicine, June 9. 2022.