Prospective study of enteroviral infections and development of beta-cell autoimmunity. Diabetes autoimmunity study in the young (DAISY).

OBJECTIVE

To determine whether there is association between infection with enteroviruses and beta-cell autoimmunity in children at elevated risk of developing type 1 diabetes.

BACKGROUND

Recent prospective and case-control studies of children who are at high risk of developing type 1 diabetes have suggested that enterovirus (EV) infections are a risk factor for beta-cell autoimmunity and type 1 diabetes.

METHODS

A nested matched case-control study of incident cases of beta-cell autoimmunity within two prospective cohorts of genetically high-risk children (cases=26, controls=39). EV infection was detected by PCR of serum, saliva and rectal swab samples.

RESULTS

Prior to autoimmunity conversion (or the equivalent age in controls), 11.5% of cases and 17.9% of controls were positive for EV infection. EV was detected in 19.5% of cases and 25.6% of controls over the whole follow-up period. Conditional logistic regression gave no evidence that the frequency of EV infection was associated with beta-cell autoimmunity. There was a trend for the mean number of EV infections found in EV-positive cases (2.2/case) to be higher than in EV-positive controls (1.2/control, P=0.08). However, there were no multiple infections prior to conversion in either cases or controls.

CONCLUSIONS

There is no evidence from this study that EV infection is a risk factor for development of beta-cell autoimmunity. Further study is needed to assess whether persistent or repeated EV infections occur frequently in individuals with beta-cell autoimmunity.