Two Franklin County children are among eight children admitted to Seattle Children’s Hospital with symptoms that indicate they may have a rare and serious neurological illness.
The state Department of Health and the hospital are investigating whether they have acute flaccid myelitis, or AFM, a disease that affects the nervous system, specifically the spinal cord.
“I’m concerned,” said Dr. Scott Lindquist, state infectious disease epidemiologist, at a Friday press conference in Shoreline.
“It is very unusual to have a clustering of these cases so close together,” he said. “And I am concerned we do not have answers yet.”
Symptoms typically include sudden weakness in at least one arm or leg, loss of muscle tone and reflexes that are weak or absent. Some patients recover fully and some are left with weakness, said Dr. Jim Owens, a pediatric neurologist at Seattle Children’s Hospital.
All eight of the children had a loss of strength or movement in one or more of their arms and legs, according to the Department of Health. They range in age from 3 to 14 years old and were admitted to the hospital between mid-September and Oct. 21.
Three of the eight children remain in the hospital, with the other five released. To protect patient privacy, officials did not say how old the Franklin County children are or whether they are still in the hospital.
At this point there isn’t evidence that would point to a single source of illness among these cases.
Dr. Scott Lindquist, Washington state infection disease epidemiologist
The other patients include three children from King County, two from Whatcom County and one from Pierce County.
Lindquist does not expect all eight of the patients to have a final determination that they have the illness.
“At this point, there isn’t evidence that would point to a single source of illness among these cases,” Lindquist said.
However, the investigation is just beginning, and all possibilities will be considered, he said.
The exact cause of acute flaccid myelitis is not known.
Many germs and viruses have been linked to the illness, including common germs that can cause colds and respiratory infections and polio and non-polio enteroviruses. None of the eight cases in the current Washington cluster have shown an association with enteroviruses, Lindquist said.
The illness also may be caused by viruses spread by mosquitoes or a condition in which the body’s immune system attacks and destroys tissue.
50 cases confirmed nationally this year through August
1 caseconfirmed in Washington state this year through August
“It is a very rare response of certain children’s bodies to common infections,” Owens said.
Preventive measures include being up to date on all recommended vaccinations, including poliovirus, and avoiding mosquitoes, according to the Centers for Disease Control. The federal agency is helping with the investigation and will determine whether the children have acute flaccid myelitis.
Basic healthy practices — such as washing hands, cleaning surfaces with disinfectant if a sick person has touched them, and avoiding close contact with an ill person — also can protect against the illness, the CDC said.
There were 50 cases of acute flaccid myelitis confirmed in the United States from January through August this year, up from 21 cases the year before. The CDC had alerted Washington state officials that the illness was on the upswing.
The CDC began tracking the cases when 120 were confirmed in the last five months of 2014. Some of the cases coincided with an outbreak of a respiratory illness caused by enterovirus-D68, but extensive clinical testing did not find a consistent pathogen.
There were no cases last year in Washington, and in 2014 there were two cases confirmed. This spring, one adult case was confirmed, Lindquist said.