WATCH: Number of cases of AFM nearly doubled in the last month: CDC

Transcript for Number of cases of AFM nearly doubled in the last month: CDC

There is an alarming new headline about that mystery outbreak affecting children, now spreading across the country. The CDC confirming 116 cases now in 31 states. They’re investigating 170 more cases. As we’ve reported here, it can start like the common cold, then the rare condition brings on polio-like symptoms, partial paralysis among them. Here’s ABC’s erielle reshef tonight. Reporter: Growing concern tonight over that rare but mysterious illness striking mainly children. The number of cases of acute flaccid myelitis or afm nearly doubling in just the last month. It can start like the common cold, but lead to polio-like symptoms like pararal ice and trouble breathing. 8-year-old tahi Toya first had a sinus infection, then lost strength in his left arm. Tahi had a droopy face, he lost his core strength, so he was unable to sit up without assistance. Reporter: There’s no cure for afm, and half of patients don’t fully recover. But tahi tonight is getting stronger after a cutting edge surgery that moved healthy nerves from his rib to his arm. What we’re doing is disconnecting a nerve from one muscle and tunneling it to a new target. Reporter: And David, the best hope for success of that surgery is within the first 18 months of diagnosis. Experts say the chances of getting afm, 1 in a million, but the CDC is now tracking this closely. David? All right, we’ll stay on it. Erielle, thank you.

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