Background: Personal protective equipment (PPE) use is required when caring for COVID-19 patients. Proper mask fitting is essential in prevention of infectious agent transmission at hospital setting.Methods and Results: We describe three cases of health care professionals (HCP) in a COVID-19 designated ward with positive SARS-CoV-2 RT-PCR results, and were found to have improperly fitted masks.Conclusion: These cases of improperly fitting masks in HCP may have contributed to their eventual COVID-19 infection. These cases raise the important issue of PPE fitting. Abbreviations: Personal Protective Equipment (PPE), Health Care Professional (HCP), Real-time PCR (RT-PCR).