Abstract: The invention provides a method of ameliorating and/or preventing a coronavirus infection in a subject, the method comprising administering to the subject a therapeutically effective amount of a sugar or a derivative thereof. The invention also provides a method of ameliorating and/or preventing a coronavirus infection in a subject, the method comprising upregulating sialylation of a glycan, downregulating N-glycosylation, and/or downregulating O-glycosylation of a virus particle of the coronavirus.