Born in Bradford Allergy and Infection Study

There is considerable scientific evidence that infections early in life may affect the risk of diseases, such as allergies, later in life. This research will investigate whether some common virus infections of children might affect how their immune system works later on. The researchers are particularly interested in cytomegalovirus CMV, EBV and VZV and will study whether the age at which children are infected changes the way they respond to the vaccines that they normally receive, e.g. tetanus. This would indicate an effect of the viruses on their immune system. This research will be conducted within the ‘Born in Bradford’ study. A small amount of blood will be taken at 12 and 24 months of age to find out when each child became infected. Some blood samples taken at age two will be used to measure the immune system response to routine vaccinations for measles, tetanus and pneumococcal disease. These results will then be linked to the CMV and EBV infection data to determine whether age at infection influences immune function. This work will help understand how the immune system develops and why some children develop diseases like asthma and eczema.

The overall aim is to assess the ‘hygiene hypothesis’ that early life infections determine later immune-related diseases, and in particular to assess the influence of age at infection with common herpes viruses on immune function. The specific objectives are to:

  1. Estimate the age-specific prevalence of CMV, EBV and VZV infection in early childhood in a multi-ethnic population.
  2. identify socio-economic, parental and infant factors associated with CMV, EBV and VZV prevalence
  3. Estimate CMV, EBV and VZV seroprevalence among pregnant women by ethnic group and country of birth.
  4. Quantify the association between age at CMV and EBV infection and immune response to vaccination. These data will be combined with other data from the ‘Born in Bradford’ cohort to examine the influence of symptomatic infections in addition to these herpes viruses in determining immune responses. The herpes virus data will also be linked to presence of atopy at age 4 in a separately funded nested case-control study, as a complementary measure of immune status.