Skip to main content
. Author manuscript; available in PMC: 2014 Apr 1.
Published in final edited form as: Lancet. 2013 Mar 22;381(9881):10.1016/S0140-6736(12)62187-4. doi: 10.1016/S0140-6736(12)62187-4

Table 1.

Infectious hypotheses for childhood ALL

Hypotheses Concepts Timing Agent Evidence
The Kinlen “population mixing” hypothesis17,19 Unusual demographic mixing of susceptible and infected individuals

  1. Herd immunity139

  2. Animal leukaemia precedents21

 Perinatal? Single novel virus? Increased incidence (transient, 2x) in multiple situations of population mixing or clusters19
The Greaves “delayed infection” hypothesis11,18 Delayed exposure to common infections in childhood under-exposed as infants

  1. Mismatch between evolutionary programming of immune system and modern (hygienic) lifestyle11

  2. Two-step pre-/post-natal natural history of ALL11

 Later “promotional” or triggering event11 One or (more probably) several common infections (bacterial or viral) Reduced risk of ALL from day care attendance in infancy140,141