Rubella And Poliomyelitis (Vaccines) Sir R. Russell asked the Secretary of State for Social Services what progress has been made with the clinical trials of vaccines against rubella and poliomyelitis produced in human diploid cells, referred to by his predecessor in answer to a Question on 25th March, 1970. Mr. Alison The manufacturer's clinical trials of rubella vaccine prepared in human diploid cells have now been completed. I understand that it will be a few months yet before the trials of poliomyelitis vaccine are completed and the results evaluated.