Antigenic relationship between chikungunya virus strains and o'nyong nyong virus using monoclonal antibodies.

Chikungunya (CHIK) strains from Africa and Asia were shown to be antigenically closely related using a panel of monoclonal antibodies (mAb) prepared against strains H817 from Africa and PhH15483 from Asia. The one-way antigenic relationship between CHIK and o'nyong nyong (ONN) viruses was demonstrated at the epitope level using the immunofluorescence and haemagglutination inhibition techniques. Results of tests with mAb against ONN virus suggest that, while ONN virus has retained most of the CHIK antigenic sites, many of the ONN epitopes have undergone sufficient conformational change such that mAbs prepared against them do not recognize sites on CHIK virus.