ABSTRACT
Objective: To summarize the clinical characteristics of patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Delta variant infection by comparing with patients with wild strain infection in Gansu Province. Methods: Totally 141 patients diagnosed with Delta variant infection(variant group)and 88 patients with COVID- 19 (wild strain group) in Gansu Province were selected, and their clinical data were retrospectively collected and compared. Results The proportion of patients with hypertension and vaccination was higher in the variant group than in the wild strain group (P < 0.05). Most of the two groups were mild and common types, and there were no statistically significant differences in the other general data (all P > 0.05). The percentages of fever, fatigue, muscle soreness, chest tightness and shortness of breath in the variant group were lower than those in the wild group, and the proportion of sore throat was higher than that in the wild group (all P < 0.05). The proportions of white blood cells (WBC) < 4.0 x 109/L, platelets (PLT) < 100x109/L, glutamyl transpeptidase (GGT) > 50.0 U/L, lactate dehydrogenase (LDH) > 240.0 U/L, blood urea nitrogen (BUN) > 7.1 mmol/L, and international normalized ratio (INR) >1.13 were all lower in the variant group than in the wild strain group (all P < 0.05);the percentage of aspartate aminotransferase (AST) > 40 U/L was higher than that of the wild strain group (P < 0.05). No significant differences were found in the alanine aminotransferase (ALT), blood creatinine (Cr), creatine kinase (CK), creatine kinase isoenzyme (CK-MB), activated partial thromboplastin time (APTT), prothrombin time (PT), calcitoninogen (PCT), or C-reactive protein (CRP) between these two groups (all P > 0.05). The proportions of abnormal chest CT, bilateral lesions, and three or more lobar lesions were significantly lower in the variant group than in the wild strain group (all P < 0.05). The proportions of treatments with interferon, ribavirin, lopinavir/ritonavir, antibiotics, glucocorticoids, immunoglobulins, hemopexin, Abidor tablets, and oxygen were lower in the variant group than in the wild strain group (all P < 0.05). The proportions of treatments with prone ventilation, anticoagulation, neutralizing antibodies, thymofacine, and hepatoprotective therapy were higher in the variant group than in the wild strain group (all P < 0.05). Thirty-five cases (53.0%) of lymphocytes in the wild strain group did not return to normal levels at discharge, and the differences in the time to recovery of lymphocytes, time to absorption of lung lesions, and time to nucle ic acid conversion between the two groups were not statistically significant (all P > 0.05). The recovery time of oxygen saturation (SaO2) in the variant group was shorter than that in the wild strain group, and the time of nucleic acid conversion and hospitalization was longer than that in the wild strain group (all P < 0.05). There were two deaths (2.3%) in the wild strain group and 0 death in the variant group, with no statistically significant difference between the two groups (P > 0.05). Conclusions: Compared with patients with wild strain infection, patients with Delta variant infection are mainly of light and common type with high vaccination coverage, smaller lung lesion involvement, shorter SaO2 recovery time, but longer nucleic acid regression time and hospitalization time, and have a good prognosis after oxygen therapy, traditional Chinese medicine, immune boosting, etc. The prognosis is good after conventional treatment.