Received: 25 August 2018
Accepted: 13 December 2018
First Online: 8 January 2019
Ethics approval and consent to participate
: We used an existing database build with the approval of the INH internal ethics council. Prior to the exploitation of the database, we obtained an authorization from the Institut National d’Hygiène of Lomé. People who participated to the free campaign gave a written consent.
: The authors declare that they have no competing interests.
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