U.S. health officials revealed that the severe respiratory illness Enterovirus D68, which typically affects children, now has 277 confirmed cases in 40 U.S. states and the District of Colombia.

Besides the worryingly high number of individuals who get infected by the disease, there is another serious concern that the virus may also cause paralysis in infected children.

The Children's Hospital Colorado reported that they have nine cases of patients that exhibited signs of nerve damage and paralysis. Of these nine patients, four were found positive for enterovirus D68. Mary Anne Jackson, from the Children's Mercy Hospital in Kansas City, Missouri said that they are also currently investigating three patients who showed symptoms that are similar to those observed in patients in Colorado.

D68 happens to be related to the virus that causes polio, the disease that crippled thousands of children around the world before a vaccine that prevents it became available, and while it isn't yet clear if D68 is indeed causing the paralysis in children, health experts have opinion on how this could be possible.

"In a circumstance like that, the virus actually infects the central nervous system, the spinal cord, causes injury to some of the cells, and that's what causes the paralysis," said William Schaffner, an infectious disease expert at the Vanderbilt University School of Medicine in Tennessee.

Among concerns right now is whether the paralysis is temporary or permanent. Schaffner said that the symptoms of paralysis will eventually ease in many children but there is still risk of a permanent damage.

"Some of these illnesses can have a permanent residual paralysis, just like the old-timey polio did, because if those cells have been destroyed, there can be some residual paralysis," Schaffner said.

Enterovirus D68 infection is marked by symptoms that range from fever, runny nose, cough, sneezing and body aches to wheezing and breathing problems that may require hospitalization. The treatments currently provided to patients only ease the symptoms and to date, no vaccine is available to prevent Enterovirus D68 infection.

Health experts said that there are ways that can reduce a child's chances of getting struck by the disease. Len Horovitz, a pulmonary specialist at Lenox Hill Hospital in New York City, said that good hygiene is still one of the best defenses against the disease.

"Hand washing is paramount, and teaching kids not to touch their faces with unwashed hands is the point," Horovitz said. "Any child or adult with flu-like symptoms or common cold symptoms should be seen, evaluated and followed by doctors for any respiratory complications."