Vaccines safely and effectively prevent the spread of infectious disease and some even prevent cancer. Now, a somewhat surprising benefit of vaccination is being suggested by a large epidemiological study that revealed that getting fully vaccinated against rotavirus in the first months of life is associated with a lower risk of developing type 1 diabetes later on.
The study is published in a paper entitled “Lower Incidence Rate of Type 1 Diabetes after Receipt of the Rotavirus Vaccine in the United States, 2001-2017” published in Scientific Reports today.
The study first showed the result that vaccinating babies against rotavirus greatly reduces their chance of getting so sick that they need hospital care. Children vaccinated against rotavirus had a 94% lower rate of hospitalization for rotavirus infection, and a 31% lower rate of hospitalization for any reason, in the first two months after vaccination. Rotavirus can cause a nasty gastrointestinal disease with symptoms that include severe watery diarrhea, vomiting, fever, and abdominal pain. Infants and young children can become severely dehydrated requiring hospitalization.
The second conclusion from the study was that children who received all recommended doses of rotavirus vaccine had a 33% lower risk than unvaccinated children of getting diagnosed with type 1 diabetes. The risk was especially lower among children who received all three doses of the pentavalent form of the vaccine than those who received two doses of the monovalent form. The pentavalent rotavirus vaccine protects against five types of rotavirus while the monovalent vaccine protects against one type. Children partially vaccinated—that is, started the vaccine series but never finished it—did not have a lower risk of type 1 diabetes.
Mary A.M. Rogers, Ph.D., an associate professor in the University of Michigan department of internal medicine and the paper’s senior author, cautioned that they cannot show a cause-and-effect relationship between rotavirus vaccination and type 1 diabetes risk. “This is an uncommon condition, so it takes large amounts of data to see any trends across a population,” said Rogers. “It will take more time and analyses to confirm these findings. But we do see a decline in type 1 diabetes in young children after the rotavirus vaccine was introduced.”
A team from the University of Michigan designed a cohort study of 1,474,535 infants in the United States from 2001–2017, using data from a nationwide health insurer. The study provides strong post-market evidence that the vaccine works.
Yet the study finds more than a quarter of American children don’t get fully vaccinated against rotavirus, and that the rate varies widely across the country. Less than half of children in New England and Pacific states were fully vaccinated. Two-thirds of children in the central part of the country were fully vaccinated.
The Centers for Disease Control and Prevention recommends that infants receive the multi-dose vaccine starting no later than 15 weeks, and finish receiving it before they are eight months old. Infants receive the vaccine in oral drops.
The new result echoes the findings of a study of Australian children published earlier this year, which found a 14% reduced risk of type 1 diabetes after the rotavirus vaccine was introduced in that country. That study, and the new one, suggest that a childhood vaccine may lead to a lower risk of a later chronic condition. It also fits with laboratory studies showing that rotavirus attacks the same kind of pancreas cells that are affected in people with type 1 diabetes.
Type 1 diabetes, once called “juvenile diabetes,” only affects a few children out of every 100,000, so having such a large pool of data can help spot trends, said Rogers. “Five years from now, we will know much more,” said Rogers. “The first groups of children to receive the rotavirus vaccine in the United States are now in grade school, when type 1 diabetes is most often detected. Hopefully, in years to come, we’ll have fewer new cases—but based on our study findings, that depends upon parents bringing in their children to get vaccinated.”