Evaluation of some methods of concentration and purification of influenza virus.

A number of techniques have been developed in the past 15 years for the concentration and purification of influenza virus, but there has been no comparative evaluation of their efficacy. In this paper the authors report on such an assessment, carried out with particular reference to the suitability of the various techniques for large-scale production of influenza vaccine, the aim being to recover a relatively pure antigen by simple means and without undue loss in the haemagglutinin and virus contents.The purest product was obtained with two cycles of aluminium phosphate treatment. Next in order came ultracentrifugation with and without methanol precipitation, red cell adsorption, single-cycle aluminium phosphate treatment, and finally the zinc hydroxide method.