It is a work that presents knowledge in 230 short articles on different topics, addressed in real time during the Covid-19 pandemic. Some of these articles have been questioned over time, but most of them are still valid and will serve as a tool to address this pandemic-syndemic and the next health crises.This enriching experience has been of great benefit, since it provides society with important reference material, with information on what should and should not be done in similar situations, with identification of data that may or may not be relevant for taking actions, with decisions that at the time seemed to be the best option but that time has disproved them, with indispensable activities and others not so much, with decisions taken and pending, with what was attended and what was left unattended, among many other situations.