The use of blood-type tattoos during the Cold War.

Background We have seen a number of individuals who received blood-type tattoos on the left side of the chest as schoolchildren in northwest Indiana during the 1950s. Objective To investigate the history of blood-type tattooing. Methods Historical research was conducted using newspaper and journal articles found in medical libraries, online archives, American Medical Association archives, Chicago Historical Society records, local medical society documents, in addition to personal interviews. Results Blood-type tattoos were used during the Cold War to enable rapid transfusions as part of a "walking blood bank" in case of atomic attack. Nationwide blood-typing programs occurred to inform individuals of their own blood types and to provide local communities with lists of possible donors. The blood-type tattooing program was part of this effort, but community-wide tattooing occurred only in two parts of the United States: Lake County, Indiana, and Cache and Rich counties, Utah. In these communities, during 1951 and 1952, schoolchildren were tattooed to facilitate emergency transfusions. Limitations Events occurred more than 50 years ago, so we relied on original documents and interviews from individuals involved in the program who are still alive. Conclusions The use of blood-type tattoos was short lived, lasting less than a year, and ultimately failed because physicians did not trust tattoos for medical information.