Human coronaviruses are important respiratory pathogens (1). These viruses have also been implicated in human neurological diseases (2, 3), and some reports have suggested an association with the demyelinating condition multiple sclerosis (4, 5, 6), although other studies cast doubt upon the role of coronaviruses in this disease (7, 8, 9, 10, 11). It has been shown that most human coronaviruses belong to one of two antigenic groups represented by isolates OC43 or 229E respectively (1, 12). The antigenic properties of these coronaviruses are thus of medical and virological interest.