JAMESTOWN -- The appearance of acute flaccid myelitis around the United States has health officials concerned about the severity of the virus but also the mysteries of its origin and effective treatment.

Also known as AFM, the rare virus is known to strike children, but adults are also at risk, said Jill Baber, an epidemiologist with the Division of Disease Control at the North Dakota Department of Health.

“It tends to hit children with underlying conditions,” Baber said.

Studies show that since 2014 around 90 percent of AFM cases involved patients who had experienced a mild respiratory illness or fever before developing AFM. The poliovirus has been ruled out as a cause of AFM, but other forms of viruses that can be dangerous to the central nervous system are suspected as causes, according to the ND Department of Health.

There is one potential AFM case involving a youth in North Dakota, Baber said. The age of the youth, residence or the hospital where treatment is being provided was not released, she said.

The Centers for Disease Control and Prevention is monitoring the case, Baber said. A number of tests need to be completed to rule out other potential health conditions, she said.

“One case is possible, and there are some others under investigation,” Baber said.

A cluster of AFM cases in Minnesota children was identified in October, according to the Department of Health. Most onset case were identified in August and October.

AFM Is a very polio-like virus, and doctors are trying to understand where it’s coming from and how it’s related to enteroviruses, Baber said. It’s alarming to see AFM in normally healthy kids, and the CDC is very interested when a hospital reports a potential case, she said.

Neurologists are using magnetic resonance imaging to identify signs of AFM, she said. There are often lesions in the gray matter of the spinal cord in AFM cases, she said.

Symptoms of AFM are sometimes confused with other viruses, but it’s odd to see normally healthy children with sudden weakness of muscle tone and reflexes, slurred speech, facial and eye drooping and difficulty swallowing, she said.

“We want people looking for those odd symptoms,” Baber said. “Look for limb weakness where a child is suddenly not using an arm or is having trouble walking.”

The symptoms can lead to serious neurologic problems, she said. Treating for viruses and physical therapy has helped patients recover in some cases, but others have not responded.

“It's scary that some kids can improve through physical therapy and some kids haven’t,” Baber said.

As an enterovirus, the best prevention is handwashing and staying home when feeling sick, Baber said. Avoiding AFM is much like avoiding any respiratory illness where a compromised immune system can open the door for other viruses and disease, she said. Make sure to have all vaccinations up to date, clean and disinfect frequently touched surfaces and toys and protect against mosquito bites, she said.