American Journal of Clinical Nutrition, Vol 9, 606-612, Copyright © 1961 by The American Society for Clinical Nutrition, Inc.

Serum Vitamin B₁₂ Levels and Incidence of Tapeworm Anemia in a Population Heavily Infected with Diphyllobothrium Latum

¹ From the Fourth Department of Medicine, Helsingfors University (address Maria Hospital), Helsingfors, Finland, and the Department of Medicine, Vasa Central Hospital, Vasa, Finland

In order to elucidate the incidence of D. latum infection, tapeworm anemia and low serum vitamin B₁₂ levels, a population in Eastern Finland was subjected to a mass examination. Of the 1,345 subjects examined, 27.2 per cent were found to have tapeworm ova in their feces. Among those who had no tapeworm ova 0.3 per cent had a combination of anemia and low serum vitamin B₁₂ level, but none had megaloblastic bone marrow. Among the worm carriers 1.9 per cent had verified (megaloblastic), and another 1.1 per cent suspect (nonmegaloblastic) vitamin B₁₂ deficiency anemia. The incidence of tapeworm anemia in worm carriers is at least 1:50. The mean serum vitamin B₁₂ levels in the tapeworm carrier and control groups were 116.4 and 273.8 µµg./ml., respectively, the difference being statistically highly significant. More than fifty per cent of the worm carriers had a serum vitamin B₁₂ concentration below 100 µµg./ml., whereas this occurred in less than 5 per cent of the control subjects. It is concluded that the incidence of tapeworm anemia is much higher than has hitherto been supposed, that vitamin B₁₂ deficiency is extremely common in D. latum carriers and that the D. latum endemy in Finland is thus to be regarded as a serious public health problem.