It seems like a common vaccine is helping unintentionally to prevent type 1 diabetes

Type 1 diabetes is on the rise all over the world, but in Australia the problem seems finally to be resolved.

For the first time since 1980, the number of young Australian children diagnosed with this autoimmune disease has begun to decline, which may be linked to the country's impressive vaccination program.

New research has shown that the curious decline of type 1 diabetes in Australia began just after the introduction of oral rotavirus vaccine, which encouraged an intuition that has existed for about 20 years.

"Although inconclusive, our latest study suggests that preventing rotavirus infection in Australian infants through vaccination could also reduce the risk of type 1 diabetes in certain infants at genetic risk," says Dr. lead author Len Harrison, a physician and researcher in molecular medicine at the University of Melbourne.

This curious correlation was discovered by the team of researchers just before the turn of the century, when they noticed that the immune markers of type 1 diabetes mellitus (T1D) resembled remarkably rotavirus infection (RV).

Since then, scientists have discovered that RV infection can trigger an immune attack of pancreatic insulin-producing cells, the organ responsible for controlling a person's sugar level and a key factor in diabetes.

When the two oral RV vaccines were introduced into Australia's National Immunization Program in 2007, they provided an opportunity for further research.

With the help of publicly available data, researchers compared the incidence of type 1 diabetes eight years before and eight years after this change.

The results suggest that the RV virus could do more than we thought. This vaccine alone has the potential to save millions of young children around the world from a serious and potentially deadly form of diarrhea. Could it also prevent the development of T1D?

This is definitely a possibility. In the years following the launch of the RV vaccine program in Australia, at a time when national coverage was estimated at 84%, the incidence of T1D decreased by 14% in children aged 0 to 4 years.

"The significant decrease (…) was not observed in children aged 5 to 14 years," says lead author Kirsten Perrett, an expert in immunization and allergies at the University of Melbourne.

"This suggests that young children may have been exposed to a protective factor that has not affected older children."

Although this does not necessarily mean that the antiretroviral vaccine stops this incurable disease, it builds on previous research suggesting that rotavirus infection could be a risk factor for diabetes.

At least in Australia this could be the case. For some reason, a Finnish study using a smaller sample and a shorter period did not reveal the same correlation, although it may be related to genetic and environmental differences between the two countries.

With a promising track, Australian researchers continue to delve into the national data, hoping to find more clues to tie these two conditions together.

"At this point, we do not yet know whether the reduction of type 1 diabetes is a permanent or transient effect, and this could only affect Australian children," Harrison said.

The takeaway message? Vaccinate, vaccinate, vaccinate. You never know what it could do better.

This study was published in JAMA Pediatrics.