Omicron (English name: Omicron, number: B.1.1.529) is a variant of the new 2019 coronavirus. Fever may return after the fever has subsided from Omicron infection. Due to the different body types and symptoms of the first fever remission may be again fever, usually requires fever reduction, antiviral and other symptomatic treatment. It is recommended that prompt medical attention be sought after the fever returns, or because the patient’s infected lung lesions have not completely resolved, the fever may manifest again after the fever has subsided. Fever due to omicron infection can be treated with medications such as ibuprofen for fever reduction, and antiviral treatment with medications such as lopinavir and ritonavir is required.