Introduction: Attendance at face-to-face courses is low in the 2nd and 3rd years of medical school in France, possibly because of a lack of interactivity. We used Moodle (an open-source course management system) to introduce blended learning on Infectious Diseases and Microbiology through interactive quizzes and sessions of online-based continuous assessment. This pre-post observational study assessed changes in students' attendance and student as well as teacher satisfaction. Methods: During the 2017-2018 academic session of Infectious Diseases and Microbiology, we used Moodle to include interactive quizzes during courses and to organize five continuous assessment sessions. Pre-post comparisons (2017-2018 vs. 2016-2017) were performed for the following outcomes: attendance rate, satisfaction questionnaire and exam performance. In addition, the students' and teachers' perception of Moodle-based interactive quizzes and continuous assessment sessions in 2017-2018 was assessed with Likert-like scales, closed and open-ended questions. A thematic analysis of the free comments was performed through inductive coding by two coders. Results: In 2017-2018 vs. 2016-2017, mean (± SD) attendance rate was higher [12.5 (± 7.2) % vs. 7.9 (± 3.5) % of students, P < 0.001] and clinical case-based courses, which encompassed 93% of Moodlebased courses in 2017-18, were more frequently considered to improve teaching and learning (81.9% vs. 73.8%, P = 0.01). Students more frequently judged the teaching organization and structure to be adequate (85.5% vs. 80.2%, p = 0.03) and more frequently recommended to next-year students that they attend courses (96.1% vs. 42.1%, P < 0.001). Conclusion: Using Moodle for blended learning on Infectious Diseases and Microbiology improved student satisfaction and attendance at face-to-face courses.