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. 2021 Aug 13;23(8):e29556. doi: 10.2196/29556

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©Alberto Eugenio Tozzi, Francesco Gesualdo, Emanuele Urbani, Alessandro Sbenaglia, Roberto Ascione, Nicola Procopio, Ileana Croci, Caterina Rizzo. Originally published in the Journal of Medical Internet Research (https://www.jmir.org), 13.08.2021.

This is an open-access article distributed under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work, first published in the Journal of Medical Internet Research, is properly cited. The complete bibliographic information, a link to the original publication on https://www.jmir.org/, as well as this copyright and license information must be included.

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Weekly number of COVID-19 confirmed cases (red), SYM (symptomatic users) sessions (yellow), and CON (users with contact with a COVID-19 case; green) sessions between February 2020 and March 2021.