Infection and leukaemia

Research into the link between infectious disease and childhood leukaemia was first published in the 1920s.

The connection between leukaemia and infection fell out of favour until the 1980s when links between other human blood cell cancers and infections were made.

Observations showed that the age distribution of leukaemia was similar to that of common childhood infectious diseases.

Many of the children with leukaemia had a record of infectious diseases around the time of diagnosis.

Doctors at Great Ormond Street Hospital proposed 'the solution to the problem of leukaemia lies rather in some peculiar reaction to infection than in the existence of some specific infective agent’.

Others believed that a specific infection was involved.

The connection between leukaemia and infection fell out of favour until the 1980s when links between other human blood cell cancers and infections were made.

The discovery that leukaemias in domestic cattle, cats and chickens were viral in origin further contributed to the re-emergence of infection hypotheses in childhood leukaemia.

Three main hypotheses

There are now three main hypotheses concerning the possible role played by infection in childhood leukaemia:

infectious exposure during pregnancy or around the time of birth increases the risk of childhood leukaemia;

the absence of infectious exposure during the first two years of life affects the development of the immune system. It also increases the risk of leukaemia following subsequent infectious exposure;

unusual patterns of population mixing introduce a new infection to previously unexposed populations and childhood leukaemia is an unusual result of such an infection.

A review of the scientific evidence

There is now a large body of research examining the relationship between childhood leukaemia and infectious disease.

Read our review of the scientific evidence by Dr Kirsten Edgar and Dr Adrienne Morgan: