ILLNESS BAFFLES CDC SCIENTISTS

Mysterious polio-like condition affecting mostly children

Researchers have little understanding of disease that can cause paralysis.

Federal health officials are worried about an increase in a mysterious and rare condition that mostly affects children and can paralyze arms and legs, with 127 confirmed or suspected cases reported as of Tuesday.

Of those, 62 cases of acute flaccid myelitis, or AFM, have been confirmed in 22 states, according to Nancy Messonnier, a top official at the Centers for Disease Control and Prevention. More than 90 percent of the confirmed cases have been in children 18 and younger, with the average age being 4 years old.

The surge in cases has baffled health officials, who on Tuesday took the unusual step of announcing a change in the way the agency will count cases in the future. They also wanted to raise awareness about the frightening condition so parents can seek medical care if their child develops symptoms, and so reports of the illness can be quickly relayed back to the CDC.

“We understand that people, particularly parents, are concerned about AFM,” said Messonnier, director of the National Center for Immunization and Respiratory Diseases. Despite extensive laboratory and other testing, CDC has not been able to find the cause for the majority of the cases. “There is a lot we don’t know about AFM, and I am frustrated that despite all of our efforts, we haven’t been able to identify the cause of this mystery illness.”

The increase in cases has been happening since 2014, usually in August and September, but only in 2014 and 2016, Messonnier said in a news briefing with reporters. The CDC knows of one child who died with the disorder in 2017.

Since officials have been unable so far to determine how the disease spreads, they are starting to count suspected cases as well as confirmed to better anticipate increases in confirmed cases over the coming months, she said.

There is no specific treatment for the disorder, and long-term outcomes are unknown. The rare but serious disorder affects a person’s nervous system, specifically the spinal cord. Neurological conditions like it have a variety of causes, such as viruses, environmental toxins and genetic disorders.

Among the cases under investigation are five reported to Maryland health officials in recent weeks, a health department spokeswoman said Tuesday. Maryland’s first case was reported Sept. 21. No known cases have been reported in Virginia or the District this year, but there were three confirmed cases in Virginia in 2016, health department officials said.

“We know this can be frightening for parents, and I know many parents want to know what signs and symptoms they should be looking out for in their children,” Messonnier said. Parents should seek medical care right away if their child develops sudden weakness or loss of muscle tone in the arms and legs.

Some patients diagnosed with this condition have recovered quickly, but some continue to have paralysis and require ongoing care, she said.

CDC began tracking the condition in 2014, when there were 120 confirmed cases. Then in 2016, there were 149 confirmed cases. Officials said it’s too early to know whether the total for 2018 will surpass those previous years. But the data reported Tuesday represents “a substantially larger number than in previous months this year,” Messonnier said.

She said it was important for parents to remember that this conditon is rare, affecting less than 1 in 1 million people under 18.