Tehran University of Medical Sciences Frontiers in Emergency Medicine 2717-3593 5 2 2020 12 20 e24 e24 Sayyed Reza Ahmadi Department of Emergency Medicine, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran Saeideh Anvari Ardakani Department of Neurology, Mashhad University of Medical Sciences, Mashhad, Iran Navid Kalani Research Center for Social Determinants of Health, Jahrom University of Medical Sciences, Jahrom, Iran Seyed Reza Habibzadeh Department of Emergency Medicine, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran Elnaz Vafadar Moradi Department of Emergency Medicine, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran Mahdi Foroughian Department of Emergency Medicine, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran 2020 11 04 2020 11 10 Introduction: While our knowledge is limited about COVID-19 immunity, recent cases of reinfection have raised concerns. Case presentation: Here, we report a case of COVID-19 reinfection after three months from recovery in a healthcare worker with negative IgM and IgG at the second infection and positive nasopharyngeal swab Reverse transcription polymerase chain reaction (RT-PCR) test despite being discharged with two negative RT-PCR tests at the first admission. Symptoms at first admission were fever, headache, sore throat, diarrhea, and vomiting and got changed to myalgia and anosmia. Conclusion: The strength of this case report is the long period (three months) between the infection and reinfection while other cases reported in literature were reinfected less than one month after their first infection. https://fem.tums.ac.ir/index.php/fem/article/view/585 https://fem.tums.ac.ir/index.php/fem/article/download/585/329