cross-tests amongst different strains complicate the picture.in planning vaccination of human beings we wonder : - ( 1 ) whether , on general epidemiological grounds , an attempt to vaccinate against influenza virus is likely to be profitable . ( 2 ) whether the production of a rise in antibodies in man will be a good guide to the immunity induced by a vaccine . ( 3 ) whether we are right in using killed virus and in fearing a live vaccine . ( 4 ) what strains we ought to use in making a vaccine . ( 5 ) when and how often we should vaccinate .
C0042211
live vaccine
C0042210
vaccine