The rising incidence of type 1 diabetes in genetically stable populations strongly suggests that environmental factors are involved. Childhood vaccinations have been introduced around the world over a period corresponding to the rise of type 1 diabetes, an immune mediated condition. It has therefore been suggested that vaccinations might increase (or decrease) the risk of type 1 diabetes in selected groups, and attempts have been made to link the introduction of new vaccines with changes in the incidence of type 1 diabetes. Linking vaccinations to increased risk of chronic or other severe diseases involves a number of methodological challenges and most available studies suffer from important limitations. Although scattered observations have suggested a somewhat increased or reduced risk associated with certain vaccinations, available data indicate that there is no association between vaccines and either increased or reduced risk of type 1 diabetes.
The second half of the twentieth century saw a Rising incidence of type 1 diabetes, and infectious agents have been plausible candidates in its aetiology ( see Viruses and type 1 diabetes). Over the same period, a world-wide effort has been made to introduce vaccination programmes designed to eradicate a number of common childhood infections.
In theory, vaccination might increase the risk of type 1 diabetes by (for example) triggering immune responses that cross-react with beta cell antigens. Alternatively, the associated boost to the immune system might even prove beneficial ( see the page on the Hygiene hypothesis) , but the best example is the eradication of congenital rubella (see The congenital rubella syndrome and diabetes) by immunization.
Vaccination against common infections
No association has been found between childhood vaccinations (polio, tetanus, diphtheria, pertussis, rubella, measles, mumps, tuberculosis, haemophilus influenza) and type 1 diabetes in a European multicentre case-control study including 900 children with type 1 diabetes. Cohort studies of children at increased genetic risk, albeit with limited number of children with endpoint, have reported no significant associations between childhood vaccinations and islet autoimmunity.
BCG and diabetes
In contrast to some earlier reports, two randomised clinical trials did not find any indications of either a preventive or detrimental effect of Bacillus Calmette-Guérin (BCG) vaccinations on residual beta-cell function among newly diagnosed patients with type 1 diabetes (BCG vaccine is or has been used in some populations for vaccination against tuberculosis).
Birth Cohort and other studies
Birth cohorts before and after initiation of national vaccination programs have not shown differences in cumulative incidence of type 1 diabetes. The lack of any significant association has been supported by most of the data published in the past few years, both for common childhood vaccinations , pandemic influenza A (H1N1) vaccine , and other vaccinations such as anthrax-, hepatitis B-, and yellow fewer vaccines given to US military personnel . If anything, data from the US military personnel suggested a lower risk after vaccination, but data should be interpreted with caution due to methodological limitations.
Although scattered observations have suggested a somewhat increased or reduced risk associated with certain vaccinations, most available data indicate that there is no association between vaccines and either increased or reduced risk of type 1 diabetes.
^ The Institute for Vaccine Safety Diabetes Workshop Panel. Childhood immunizations and type 1 diabetes: summary of an Institute for Vaccine Safety Workshop. Pediatric Infectious Disease Journal 1999;18:217-222.
^ Wraith DC, Goldman M, Lambert PH. Vaccination and autoimmune disease: what is the evidence? Lancet 2003;362:1659-1666.
^ The EURODIAB Substudy 2 Study Group. Infections and vaccinations as risk factors for childhood type I (insulin-dependent) diabetes mellitus: a multicentre case-control investigation. Diabetologia 2000;43:47-53.
^ DeStefano F, Mullooly JP, Okoro CA, Chen RT, Marcy SM, Ward JI, Vadheim CM, Black SB, Shinefield HR, Davis RL, Bohlke K. Childhood vaccinations, vaccination timing, and risk of type 1 diabetes mellitus. Pediatrics 2001;108:E112.
^ Hviid A, Stellfeld M, Wohlfahrt J, Melbye M. Childhood vaccination and type 1 diabetes. N Engl J Med 2004;350:1398-1404.
^ Duderstadt SK, Rose CE, Jr., Real TM, Sabatier JF, Stewart B, Ma G, Yerubandi UD, Eick AA, Tokars JI, McNeil MM. Vaccination and risk of type 1 diabetes mellitus in active component U.S. Military, 2002-2008. Vaccine 2012;30:813-819.
^ Bardage C, Persson I, Ortqvist A, Bergman U, Ludvigsson JF, Granath F. Neurological and autoimmune disorders after vaccination against pandemic influenza A (H1N1) with a monovalent adjuvanted vaccine: population based cohort study in Stockholm, Sweden. BMJ 2011;343:d5956.