New numbers from the Centers for Disease Control and Prevention show that the number of children with acute flaccid myelitis, or AFM, continues to rise nationwide.

There are now four confirmed cases in Georgia, according to the CDC. In October, there were three confirmed cases in the state.

So far in 2018, there are 158 confirmed cases of AFM across 36 states. Overall, 311 reports of AFM have been reported by patients this year. Those additional cases are still being investigated, according to the CDC.

In 2017, there were 35 confirmed cases of AFM across 16 states.

The disease is a rare, polio-like virus, and there is no known single cause. It can be caused by viral infections, environmental toxins and genetic disorders, according to Georgia health officials.

The Centers for Disease Control and Prevention has been investigating more than 360 possible cases of acute flaccid myelitis dating back to 2014.

The disorder, which mainly affects children, can paralyze a child's arms and legs. The average age of AFM patients is 4 years old, said Nancy Messonnier, director of the CDC's National Center for Immunization and Respiratory Diseases.

The CDC said the cause of most AFM cases is unknown, but a few cases have been linked to other viruses. Symptoms are similar to poliovirus, West Nile virus and adenoviruses, which makes it difficult for doctors to diagnose.

Symptoms include drooping face and eyelids, difficulty with eye movement and swallowing, and slurred speech. In severe cases, children might have trouble breathing and need a ventilator because of muscle weakness.

There is one documented report of a child dying from AFM in 2017.

There is no specific treatment for AFM, and the long-term outcomes for patients are unknown.

Georgia health officials said the best way to prevent AFM is to make sure children stay healthy by washing their hands, covering their mouth when they sneeze, stay home when sick and stay vaccinated.

Officials said parents should contact a health provider as soon as possible if they see any symptoms of AFM in a child -- especially if they have trouble lifting their arm.