HC Deb 16 November 1945 vol 415 c2629W
Mr. P. Freeman

asked the Minister of Health to what extent it has been found that the exemption from vaccination of about 50 per cent. of the children born in this country during the past 30 years has led to an increase in the incidence of smallpox in that period as compared with the previous 30 years.

Mr. Bevan

It is not possible to relate the incidence of smallpox during the period mentioned simply to the extent of infant vaccination since account must be taken of other controlling factors influencing the history of the disease in this country during that period.