The illness has hospitalized nearly 30 kids with symptoms as severe as paralysis of their arms and legs.

The children were hit so quickly that parents barely had time to react.

Even more frightening, is the fact that none of the children who were affected have regained use of their limbs.

The first cases popped up in 2012, and doctors call the affliction "polio like."

The Los Angeles Times reports doctors think the culprit might be a strain of the enterovirus, a malady in the same family as polio.

One pediatric neurologist told USA Today "what's we're seeing now is bad."

Just how bad is shocking.

"The best-case scenario is complete loss of one limb, the worst is all four limbs, with respiratory insufficiency, as well. It's like the old polio," he continued.

While saying the illness is still rare he warns “we are asking any families who notice a sudden onset of weakness to see their doctors immediately."

So far there have been no cases outside California, but health workers say more may be found once health-care workers are aware and look for symptoms.

More here.