To analyze the clinical characteristics of re-positive patients infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) delta strain.

The clinical data of four patients readmitted for SARS-CoV-2 delta variant strain infection in Beijing Ditan Hospital, Capital Medical University from May 2021 to October 2021 were analyzed, retrospectively.

Total of 2 male and 2 female were collected, with the median age as (36.75 ± 21.55) years old (11-63 years old). First hospitalization: 2 cases were general type, 1 case was mild type, and 1 case was asymptomatic infected. All the re-positive specimens were nasopharyngeal swabs. Clinical symptoms were mild when patients were re-positive of SARS-CoV-2 nucleic acid, only one patient with transient chest distress; no obvious clinical symptoms of fever, cough, pharyngalgia and gustation occurred. Most laboratory indicators of re-positive patients (blood routine examination, liver and renal function, inflammatory indicators) after re-admission were roughly normal. There was no change in chest CT of re-positive inpatients compared with mild type and asymptomatic infected inpatients, and the general type infected patients with pulmonary infection showed absorption and improvement compared with those before re-positive chest CT. The duration of re-hospitalization was shorter than that of the first hospitalization [(11.5 ± 4.95) d vs. (29.75 ± 2.12) d], with significant difference (t = 6.949, P < 0.001).

The condition of patients with re-positive SARS-CoV-2 nucleic acid delta strain continues to improve, but as a nucleic acid detection phenomenon, it has no significant clinical significance, but the cause of re-positive SARS-CoV-2 nucleic acid still needs further discuss.