The blood donor: detection and magnitude of cytomegalovirus carrier states and the prevalence of cytomegalovirus antibody.

Interest in transfusion-associated Cytomegalovirus (CMV) infections began with the recognition that the overwhelming majority of cases of late-onset postperfusion mononucleosis were heterophile negative (1, 2). In 1965 Klemola and Kaariainen (3) associated heterophile-negative mononucleosis with CMV infection, and 1 year later the same group documented the association ofCMV infection with heterophile-negative posttransfusion mononucleosis (4). Those patients experiencing CMV infection had not undergone extracorporeal perfusion but had been transfused with large volumes of fresh blood, which implied that asymptomatic carriage of CMV might be quite common. This supposition seemed to be borne out by Diosi et al. (5) in work published in 1968 which reported CMV isolation from the peripheral leukocytes of 2 out of 35 healthy blood donors. Since that time peripheral leukocytes from over 1500 blood donors have been inoculated into cell culture for virus isolation, but no CMV has been recovered. This work has been done in various parts of the world including Bristol, England (6), Pittsburgh (7), Cleveland (8), Atlanta (9), Houston (10), Kansas City (1 1), and Seattle (12). Prospective studies have examined the incidence of CMV infection by serology in patients receiving multiple blood transfusions. Table 1, taken from Randall and Plotkin (13), lists these studies which have shown posttransfusion infection frequencies ranging from 21 to 38%. It is noteworthy that 10 to 15% of those infected developed the postperfusion syndrome. At this point it is important to emphasize the difference between infection and disease. "Disease" is a very simple English word that means just what it says.... dis ease, or loss of comfort. "Infection", on the other hand, means the establishment of a host-parasite interaction and need not lead to damage to the host. There are many ways of detecting this interaction, ranging from isolation of the agent to evidence of the immunological response in the host. This table shows evidence of infection. Table 2 is taken from a paper by Krech (18) and shows the distribution of CMV complement Fixing (CF) antibodies in healthy blood donors in different parts of the world. Antibody prevalences range from 40% in highly industrialized areas to 100% in developing countries. It is interesting that antibody prevalences in Japan and Hong Kong are in excess of 90%, even though they cannot be considered developing areas. Table 3 is a summary ofCMV CF antibody prevalence studies in blood donors living in Europe, Australia, and North America. The low prevalence reported in the study of Monif et al. (24) can be explained by the fact that the majority of the donors in Gainesville are college students, thus young and likely to be middle class. Additional studies reporting low antibody prevalences are those of Jack and McAuliffe