§ Mr. Viantthe Minister of Health what tissue the two firms who are manufacturing anti-polio vaccine use as a basis for the preparation.
§ Mr. Viantthe Minister of Health to what extent animals are being used in the intensive tests that are being made as to the exact effects of anti-polio vaccine; what condition results when the vaccine is dangerous or capable of communicating poliomyelitis; and what condition results when the vaccine is said to be safe.
Mr. Iainasked Whilst most of the test for anti-poliomyelitis vaccine are carried out in test tubes, it is necessary to test each batch for safety by inoculating monkeys. If the vaccine contains the living virus the monkeys may develop poliomyelitis. If the vaccine is safe, the monkeys suffer no ill effects.
§ Mr. Viantthe Minister of Health what proportion of the Mahoney strain of poliomyelitis virus is used in the manufacture of poliomyelitis vaccines in this country.
Mr. Iainasked I understand that the vaccine so far manufactured in this country contains virus strains of each of the three known types of roughly equal proportions. The strain of Type I virus which has hitherto been used has been the Mahoney strain. None of this vaccine has been used here except for laboratory purposes. The Medical Research Council has advised that no vaccine containing the Mahoney strain should be used in the immunisation of children, and investigations are proceeding with a view to replacing the Mahoney strain.