Cavalcante, T., Barboza, W., & Martins-Filho, P. R. (2023). The vaccination status of COVID-19 hospitalized patients during the Omicron BQ.1.1 wave in Northeast Brazil suggests the need for a fifth booster dose in the elderly, with a time since the last dose of more than 6 months . EXCLI Journal, 22, 169–172. https://doi.org/10.17179/excli2023-5807