A measles outbreak has hit the midwestern state of Minnesota, with 50 cases reported in recent weeks.

Health officials say at least 45 cases were among children in the Somali-American community in the city of Minneapolis. Nearly all of those affected were not vaccinated against measles.

Measles is a serious disease that can cause breathing problems, brain swelling, or even death. It spreads very easily among unvaccinated people.

U.S. health officials recommend that all children receive a combined vaccine to protect against measles, mumps and rubella. This combination vaccine is called MMR. But many parents in the Somali community oppose vaccinations because they believe they can cause a child to develop autism.

A 2014 study by the American Board of Family Medicine found that 35 percent of Somali parents surveyed in Minneapolis believed the MMR vaccine causes autism. Just 8 percent of non-Somalis held the same belief.

Autism, also known as Autism Spectrum Disorder, or ASD, is a developmental disability. It affects a person's ability to communicate and do things with other people.

The University of Minnesota reported in a 2010 study that about one in 32 Somali children aged 7-9 in Minneapolis developed ASD. Another highly publicized study from a British researcher in 1998 linked autism to the MMR vaccination.

The 1998 study was later discredited and withdrawn by the British journal The Lancet, which reported it. Other research in recent years has failed to support the 2010 study's findings.

One major study involving 95,000 American children was released in 2015. It found no harmful link between the MMR vaccine and ASD, even in children already at higher risk for ASD.

Other American communities with low vaccination rates have also experienced measles outbreaks in recent years.

Dr. Mohamed Hagi Aden is with Regions Hospital in St. Paul, Minnesota. He told VOA's Somali Service all parents should inform themselves about the latest research suggesting no link between the MMR vaccine and autism.

The Minnesota Department of Health is taking steps to win back trust in vaccines. Two Somalis are now working with the department on outreach efforts. One visits mothers' groups, day care centers and schools to talk about vaccines. The other informs parents about autism and provides information about resources for special-needs children.

Minnesota health officials have requested $5 million in state money to deal with the measles emergency, as well as other recent outbreaks of tuberculosis and syphilis.

I'm Bryan Lynn.

Mohamed Olad Hassan and Steve Baragona reported on this story for VOA News. Bryan Lynn adapted it for Learning English, with additional material from the Associated Press and other sources. Hai Do was the editor.