Background Positive results from real-time reverse-transcription polymerase chain reaction
(rRT-PCR) in recovered patients raise concern that patients who recover from coronavirus …

Background Waning immunity occurs in patients who have recovered from Coronavirus
Disease 2019 (COVID-19). However, it remains unclear whether true re-infection occurs …

Background Waning immunity occurs in patients who have recovered from COVID-19.
However, it remains unclear whether true re-infection occurs. Methods Whole genome …

To the Editor—The rapid acquisition of herd immunity appears to be the only way out of the
coronavirus disease 2019 (COVID-19) pandemic. However, the strength and duration of …

Reports of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) reinfection have
raised important questions about the strength and durability of the immune response to …

ABSTRACT SARS-CoV-2 reinfection rate is low. The relative severity of the first and second
episodes of infection remains poorly studied. In this study, we aimed at assessing the …

Background The degree of protective immunity conferred by infection with severe acute
respiratory syndrome coronavirus 2 (SARS-CoV-2) is currently unknown. As such, the …

Background A novel coronavirus (CoV), severe acute respiratory syndrome (SARS)–CoV-2,
has infected> 75 000 individuals and spread to> 20 countries. It is still unclear how fast the …

To the Editor—We have detected a confirmed case of reinfection with severe acute
respiratory syndrome coronavirus 2 (SARS-CoV-2) with the second episode due to the “new …

Background Some COVID-19 cases test positive again for SARS-CoV-2 RNA following
negative test results and discharge, raising questions about the meaning of virus detection …