Community Clusters of Childhood Leukemia and Lymphoma: Evidence of Infection?

Abstract

Information suggesting that infection may be an underlying cause of childhood leukemia and lymphoma includes the occasional appearance of cases in time-space clusters within communities and increased incidence after communities experience marked population influxes (population mixing). Among 50 clusters involving cases of childhood leukemia and lymphoma investigated in the United States in 1961-1977, eight showed suggestive evidence of underlying infectious causation. In seven of the eight communities, case occurrence was associated with the attendance of patients or their siblings at particular schools or with family participation in particular church groups. In five, rapid population growth had occurred. Other findings included the possible association of cases with unusual patterns of infectious disease (rheumatic illness in one community, chickenpox in another) and with other childhood diseases, including other forms of childhood cancer. In one community, two cases of Burkitt's lymphoma occurred at the same time, and a third case arose 3 years later in boys living in a newly developing neighborhood. Such community observations support the need for continued biologic research regarding the possible role of infectious agents in childhood leukemia and lymphoma.

The Epidemiology of Childhood Leukemia with a Focus on Birth Weight and Diet

“…Numerous such investigations of childhood leukemia have been conducted without any firm conclusions as to causality. 86,87 A major reason is the so-called "Texas Sharpshooter Effect," in which one shoots first and draws a bull's-eye around the bullet holes subsequently. 88 Spatiotemporal boundaries are often specified post hoc, making it seem that disease incidence is unusually high.…”

Acute Lymphoblastic Leukemia in Children

“…The incidence is lowest in North Africa and the Middle East, and highest in the industrialized Western countries, suggesting that this may reflect more exposure to environmental leukemogens [6]. Numerous investigators have reported the occurrence of leukemic clusters in different geographic areas, thus pointing towards infectious and/or environmental causes of at least some cases of ALL [14][15][16][17]. Several studies have suggested a link between maternal reproductive history and the risk of ALL.…”

Cancer incidence in the vicinity of Finnish nuclear power plants: an emphasis on childhood leukemia

“…Clusters of childhood leukemia have been shown not only in the vicinity of nuclear installations [16] but also in other locations [17]. Incidence of childhood leukemia has been increasing since the end of 1970 in the developed countries [18].…”