Childhood leukaemia and poliomyelitis in relation to military encampments in England and Wales in the period of national military service, 1950-63.

Abstract

Objective-To determine if any excess of childhood leukaemia was associated with the large and increasing numbers of national military servicemen in 1949 and 1950, particularly in rural districts. This would be a further test of the hypothesis that childhood leukaemia can originate in an infection, the transmission of which is facilitated by an increased number of unaccustomed contacts in the community.Design-Rural and urban districts, aggregated by county, were ranked by proportion of servicemen, and five groups containing similar numbers of children were created. In addition, individual local authority districts were ranked and grouped in tenths. Mortality from childhood leukaemia 1950-3 was examined in these groups. Data on infectious diseases were also examined, as well as data on leukaemia in later periods.Setting-England and Wales. Subjects-Children aged under 15 years.Results-In 1950-3 but not subsequently a significant excess of leukaemia in children under 15 was found in the fifth of county groupings with the highest proportions of servicemen. This was due mainly to a significant excess in children under 2 years (and especially in those under 1 year) in rural districts. It was confirmed among the tenth of local authority districts with the highest proportion of servicemen. These rural areas showed significantly more notifications of, and deaths from, poliomyelitis among children than the rural average.Conclusions-The findings support the infection hypothesis. That the excess of leukaemia was greatest in children under 1 year suggests transmission of infection among adults and thence to the fetus. The pattern of spread of poliomyelitis may also have been influenced by the presence of large numbers of servicemen.

Population mixing, socioeconomic status and incidence of childhood acute lymphoblastic leukaemia in England and Wales: analysis by census ward

“…A similar pattern was found with diversity of origin of adult incomers, although the association was not significant. This is consistent with the results of several of Kinlen's studies in which the relevant population mixing was necessarily attributable to adults, because it was defined in terms of employment Kinlen, 1997) or military service (Kinlen and Hudson, 1991). Similar results were, however, found in Kinlen's studies of rural new towns (Kinlen et al, 1990) and of rural areas receiving large numbers of evacuees in wartime (Kinlen and John, 1994), where the population mixing was attributable substantially or even totally to children.…”

Space-time clustering analyses of childhood acute lymphoblastic leukaemia by immunophenotype

“…The data are also consistent with Kinlen's hypothesis of population mixing (Kinlen, 1995), particularly in relation to one study which demonstrated a marked excess of leukaemia in children under 1 year of age suggesting an infection during pregnancy (Kinlen and Hudson, 1991). The differences between males and females may be indicative of an immune modulation hypothesis, with females being more susceptible to leukaemogenic events resulting from exposure to infection.…”

Spatial temporal patterns in childhood leukaemia: further evidence for an infectious origin

“…Although exposure to infections is not often considered as a factor in the aetiology of infant leukaemia, one of Kinlen's studies found an excess only for children under the age of 2 years and the largest excess was for infants (Kinlen and Hudson, 1991); as noted above, EUROCLUS found infants to be intrinsically involved in spatial clustering, but the MLL status of the infant cases is unknown. Thus, the present results cannot be interpreted as indicative of an infectious aetiology for infant leukaemias having MLL gene rearrangements.…”