Diagnosis of human coronavirus infection by immunofluorescence: method and application to respiratory disease in hospitalized children.

Rabbit antisera were prepared against coronavirus strains 229E and OC43 and used successfully to detect viral antigen in epithelial cells shed from the nasopharynx of symptomatic volunteers who had received coronavirus inocula three to four days before. The same serologic reagents were applied to nasopharyngeal secretion cells obtained from 106 infants and children hospitalized with respiratory tract disease and apparently not infected with conventional respiratory viruses. No coronavirus infections were detected by this method. It appears that coronavirus OC43 or 229E infections were not common in children in Tyneside hospitals during the period of study. However, fluorescence is a useful method for detection of coronavirus infections in symptomatic human subjects.