(SAN FRANCISCO) -- There's a medical mystery in California. Doctors are stumped about what has caused polio-like symptoms in as many as 25 children over the past 18 months.
In some children the symptoms initially appear as the common cold, and then very quickly -- within two days -- "they have moderate to severe weakness that affects one limb or more," Dr. Emmanuelle Waubant, a neurologist at the University of California San Francisco, said.
Testing confirmed the children do not have polio, but what they do have, doctors don't know.
"We actually found that in the cases we checked for a level of antibodies against polio vaccine, they had amounted to a very good immune response so we knew that the immune system was able to prevent any infection with polio," Waubant said.
Some of the patients, because they had more widespread involvement of their spinal cord, were weak in both arms and legs,. They were so severely weak that they couldn't move at all their arms and legs, he said, describing the symptoms.
Waubant said a few cases have turned up in Asia of children with a similar disease, and that's why experts think we're seeing the same illness in California.
All cases have been in California and only in the past 18 months.
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