Secondary data from Brazilian tweets about COVID-19

These datasets contain secondary data extracted from Brazilian tweets about the COVID-19 pandemic. These data were generated between March, 2020 and May, 2021. Due to the Twitter' restrictions , it was not possible to share the raw data. Also, respecting the users privacy and in accordance with the recommendations of the Brazilian Research Ethics Committee, neither tweets ID can be shared here. So, a set of scripts were applied on raw data to extract useful information and create these datasets for further research. The files initiated with top prefix contain the most cited words by day in three categories: general tweets, vaccine-related tweets and verified accounts tweets. Files starting with the prefix subject, on the other hand, contain the daily count of mentions according to the following categories: symptoms, drugs, vaccines, brands or vaccine manufacturers and the count per day. As the data are associated with the post date, studies can be developed considering the temporal aspect in order to compare the perception of users on a given subject over time. It is important to note that some issues have become more important over time, especially in relation to vaccines.