In general , a whole virion serves as a simple vaccine antigen and often essential material for the analysis of immune responses against virus infection .
However , <*> it is necessary to take precautions against laboratory - acquired infection .
In general , a whole virion serves as a simple vaccine antigen and often essential material for the analysis of immune responses against virus infection .
However , to work with highly contagious pathogens , it is necessary to take precautions against laboratory - acquired infection .