Type 1 diabetes

A drop in the number of young children diagnosed with type 1 diabetes. This associates with the introduction of routine rotavirus vaccination of Australian infants. This is according to a new study by Melbourne researchers.

The researchers investigated the number of Australian children diagnosed with type 1 diabetes from 2000 to 2015. They found that type 1 diabetes diagnoses in children aged 0-4 years declined from 2007 — the year. Because, rotavirus vaccine was there as a routine infant vaccination.

This is the first time the rate of type 1 diabetes in young children has fallen since the 1980s. It was not conclusively linking the rotavirus vaccine with protection against type 1 diabetes. Still the discovery builds on earlier research suggesting natural rotavirus infection may be a risk factor for type 1 diabetes. The study was published in JAMA Pediatrics.

Decline in type 1 diabetes

Since the 1980s, the incidence of type 1 diabetes has steadily increased in Australia and worldwide. But scientists are still trying to understand the reasons for this increase. Type 1 diabetes is a serious, lifelong autoimmune condition. In this the body’s immune system destroys cells in the pancreas that produce insulin. It is a hormone that controls the level of glucose in the blood.

The researchers investigated the number of Australian children diagnosed with type 1 diabetes each year since 2000. The team observed that after 2007 the rate of type 1 diabetes decreased in children aged 0-4 years.

“The significant decrease in type 1 diabetes that we detected in young children. After 2007 it was not visible in older children aged 5-14. This suggests a protective factor was there for the young children. Which maybe didn’t impact older children,” Dr Perrett said.

“We observed the decline in the rate of type 1 diabetes in children born after 2007 coincided with the introduction of the oral rotavirus vaccine onto the Australian National Immunisation Program in 2007.”Doctors give the rotavirus vaccine routinely to Australian infants aged 2 and 4 months to protect them against a severe, potentially life-threatening form of diarrhoea.

Exploring the connection

Professor Len Harrison from the Walter and Eliza Hall Institute said the discovery followed on from earlier research implicating rotavirus infection in the development of type 1 diabetes.

“Twenty years ago our team revealed an association between the appearance of immune markers of type 1 diabetes in children and rotavirus infection. Subsequent studies in laboratory models suggested rotavirus infection of pancreatic cells can trigger an immune attack against the insulin-producing cells — similar to what occurs in type 1 diabetes,” he said.

“While not conclusive, our latest study suggests that preventing rotavirus infection in Australian infants by vaccination may also reduce their risk of type 1 diabetes. So. we will continue this research to look more closely at the correlation. We will compare the health records of young children with or without type 1 diabetes. In conclusion, professor Harrison said that “At this stage we don’t yet know whether the reduction in type 1 diabetes is a permanent effect or transient, and it may only be relevant to Australian children,”.