Bouzidi Malek AridjBouteraa HouriaBenaroua ImeneEncadreur: YAKHLEF.W2024-11-052024-11-052022579/162-MBhttp://dspace.univ-khenchela.dz:4000/handle/123456789/7367Abstract: Hand sanitizers (HS) have invaded our lives since the onset of COVID-19. These small bottles are multiplying in pharmacies, stores, schools, our handbags and help to protect us against the coronavirus and its variants. Our survey conducted on the proper use of HS among students of the NLS faculty (Abbes Laghrour Khenchela University) showed that 63% of students using these disinfectants are female. Insufficient knowledge on the use of HS was reported among the majority of students surveyed (> 70%). The results of the evaluation of the microbiological effectiveness of HS, in vivo, showed that 50% of the products tested were ineffective in terms of disinfection; this is perhaps due to an insufficient alcohol level to guarantee their biocidal action. Indeed, 60% of the HS tested and used by the students participating in our survey are deemed non-compliant due to incomplete labeling which does not mention the alcohol content in these products. Finally, the study of the macroscopic, microscopic and biochemical characters of the isolated bacterial colonies has allowed the identification of several white Staphylococci with Negative Coagulase, Staphylococcus aureus, Pseudomonas luteola and Pasteurella pneumotropica.frThesis