Rare Paralysis Cases in Children Are Investigated in Minnesota

Health authorities in the United States said this week that they were investigating an unusual spike in cases of a rare condition that causes limb paralysis and severe muscle weakness in children.

Since mid-September, six cases of the condition, acute flaccid myelitis, in children under 10 years old have been reported to the Minnesota Department of Health, the agency said. Another two possible cases are pending confirmation, officials said.

The number of cases of the illness, also known as AFM, is the highest in the state since 2014, when there were three reported cases, the health authorities said. Minnesota typically records one case of AFM each year, and some years it does not have any at all, the department said. Officials have not found a specific cause for the illness.

On Tuesday, the health authorities said three children suspected to have AFM were being treated at UPMC Children’s Hospital of Pittsburgh.

The Centers for Disease Control and Prevention says it has seen an increasing number of people across the U.S. with the serious condition in the past four years.

AFM affects the nervous system and causes, mostly in children, paralysis similar to polio. The signs include sudden muscle weakness in the arms or legs; neck weakness or stiffness; a drooping face or eyelids; difficulty swallowing; and slurred speech, health officials say.

Parents usually notice the child’s loss of the use of an arm or a leg. That was the case with Orville Young, a 4-year-old boy in Minnesota who lost mobility in his right arm and had difficulty sitting up and moving his legs.

He had just recovered from a cold and fever in July.

His mother, Elaine Young, told KSTP-TV in a report published Monday that her son had received a diagnosis of AFM. An MRI scan showed he had an abnormality in his spinal cord.

“By this point, his paralysis had already progressed to his trunk,” she said. “He was weak, he couldn’t walk. They were really worried about his breathing.”

Orville spent six days in the hospital being treated with steroids and undergoing physical therapy, she said.

From August 2014 through August 2018, the CDC received reports of 362 AFM cases, mostly in children, it said.

This year, 38 cases of AFM had been confirmed in 16 states through August, its latest figures showed.

That figure does not include the six new cases in Minnesota and the possible two other cases there, the CDC said in an emailed response to questions.

In a separate statement, the agency said that it was “aware of several patients in Minnesota who have clinical symptoms” consistent with AFM and that it was “working closely with the Minnesota State Health Department to investigate these cases.”

It added that it was consulting a neurologist in each case “to better understand this illness.”

Even with an increase in cases since 2014, AFM is considered a very rare condition, with fewer than 1 in 1 million people in the U.S. getting the illness, the CDC said.

The exact reasons that the condition appears are not known, but neurological conditions have a variety of triggers, such as viruses, environmental toxins and genetic disorders, the CDC said.

In 2014, doctors believed the cases might be linked to infection with enterovirus 68, a respiratory virus, according to a New York Times article.

“There were not necessarily a lot of cases that had been noticed before” 2014, said Jayne Griffith, the Minnesota Department of Health’s senior epidemiologist. “So at that point, where it burst onto the scene, the CDC took initiatives to make this condition reportable.”

Griffith said the cases usually come to light when parents notice acute muscle weakness or paralysis in their child and bring them to a health provider. A clinical diagnosis, which was given in the state’s six new cases, involves an MRI and a scan or a tap of the spine, which detects inflammation associated with AFM.

“There is obviously a lot of concern about it, but it is rare,” Griffith said.

Cynthia Kenyon, another Minnesota Department of Health epidemiologist, said that spinal inflammation disorders could spring from viruses, other pathogens or toxins. After a diagnosis is made, health providers and investigators try to retrace the path of the illness to its source.

“From what my understanding is, if there is an external causal agent, it may be difficult to determine when the exposure to that agent occurs,” Kenyon said. “And then there is lag time until the spinal inflammation.”

Investigators are still collecting data on the two unconfirmed cases in Minnesota, which involved children under the age of 10 who displayed symptoms in the summer, Griffith said.

AFM is not known to be contagious, she said.

There is no single treatment for AFM, but a neurologist may recommend therapy. A 2-year-old girl underwent occupational therapy and a nerve transfer operation after she lost the use of her right arm, the Children’s Hospital of Philadelphia said last month.

The CDC does not yet know the long-term effects of AFM Some patients have recovered quickly, while others continue to have paralysis, it says.

In Minnesota, health officials have fielded calls from the public and doctors about how to prevent the onset, Griffith said.

Health officials in Minnesota and at the CDC have recommended general preventive steps. They include hand-washing, mosquito repellent to try to protect against West Nile virus, and vaccinations for polio, even though there is no known link to AFM.

“We think that in some cases, there might be a virus or some pathogen that you are initially infected with,” Kenyon said. “Since we don’t see a clear association with all of our cases with a particular virus or pathogen, the best we can do right now is to make sure you are doing everything you can.”