Reference:
Chemaitelly, H., Ayoub, H. H., AlMukdad, S., Coyle, P., Tang, P., Yassine, H. M., Al-Khatib, H. A., Smatti, M. K., Hasan, M. R., Al-Kanaani, Z., Al-Kuwari, E., Jeremijenko, A., Kaleeckal, A. H., Latif, A. N., Shaik, R. M., Abdul-Rahim, H. F., Nasrallah, G. K., Al-Kuwari, M. G., Butt, A. A., Al-Romaihi, H. E., Al-Thani, M. H., Al-Khal, A., Bertollini, R., & Abu-Raddad, L. J. (2022). Duration of mRNA vaccine protection against SARS-CoV-2 Omicron A.1 and BA.2 subvariants in Qatar. Nature Communications, 13, 3082. https://doi.org/10.1038/s41467-022-30895-3
Summary:
The study investigated the duration of protection offered by mRNA COVID-19 vaccines against Omicron subvariants BA.1 and BA.2 in Qatar. It found that the effectiveness of the BNT162b2 vaccine was highest in the first three months post-second dose, with a decline to approximately 10% thereafter. After a booster, effectiveness increased to about 60% for BA.1 and 44% for BA.2, but also waned over time. Notably, the vaccines provided robust protection (70–90%) against severe outcomes like hospitalisation and death, reinforcing the importance of booster doses. These findings highlight the need for ongoing vaccination strategies to maintain public health during emerging COVID-19 variants.