BCG vaccination and cancer mortality

Summary The mortality rate from leukemia and other neoplastic diseases for the years 1957–1969 was compared in 85,356 BCG-vaccinated newborns at Cook County Hospital, Chicago, and 534,870 nonvaccinated population in Chicago (all black). All cases of cancer deaths under 20 years of age in the black population of Chicago were obtained from death certificates at the Chicago Board of Health. The total black population 20 years of age and under was determined by demographic means from the Chicago Board of Health birth records, adjusted for deaths under the period of study. There were 13 deaths among the vaccinated for a rate of 1.17/100,000/year and 306 deaths among the nonvaccinated for a rate of 4.39/100,000/year. The difference was statistically highly significant (p<0.001). This was a reduction of 74% in the vaccinated group as compared to the nonvaccinated. There were no deaths from malignancies in the under 1 year of age group in the vaccinated, but a drop in the rates to 50% or less in the later age groups (except 10–14 years) in the vaccinated as compared to the nonvaccinated. Thus revaccination at given intervals (1–2 years) is recommended. The National Cancer Institute checked death reports due to cancer elsewhere in the country in our vaccinated population. To reduce the possibility of error, deaths due to trauma in the two groups were determined. No differences in the rates were found. The major categories of neoplasms for this age group were (1) leukemia, (2) central nervous system, (3) lymphoma, and (4) bone and connective tissue. This was a retrospective study. Statistically designed, controlled studies may provide definite conclusions.     

Disseminated tuberculoid lesions in infants following BCG vaccination.

The records of 830 consecutive autopsies at Children''s Hospital, Winnipeg revealed that 26 of the 36 infants (34 Canadian Indian, 1 Inuit and 1 Caucasian) given BCG vaccine shortly after birth had tuberculoid granulomas in various sites, including the vaccination site, regional lymph nodes, liver, spleen, lung, bone marrow and salivary gland. Mycobacterium bovis, BCG type, was identified in three of the four cases in which isolation was attempted. The principal causes of death had been sudden infant death syndrome and respiratory tract infections. None of the infants had histologic evidence of an immune deficiency. However, it is possible that in two cases the dissemination of BCG was enhanced by a temporary immunologic defect induced by malnutrition.