System, method and program product for scanning files for a virus. A multiplicity of files which have been accessed since a previous virus scan are identified. Based on the identifications of the multiplicity of files which have been accessed since a previous virus scan, the multiplicity of files are scanned for viruses. Other files which have not been accessed since the previous virus scan are not scanned for viruses. The scanning can be limited to those files which have been updated since the previous virus scan. The scanning of the multiplicity of files for viruses can be performed by scanning the multiplicity of files in a priority order. The priority order can be based on a type of extension of the multiplicity of files or an elapsed time since the files of the multiplicity were accessed and not scanned for viruses.