Q & A: Rare polio-like disease emerges in California

(Updated March 25, 2014.)  Keith Van Haren, MD, pediatric neurologist at Lucile Packard Children’s Hospital Stanford and an instructor in neurology and neurological sciences at the School of Medicine, recently collaborated with the University of California-San Francisco’s Emmanuelle Waubant, MD, PhD, to identify a very rare disease that shares some characteristics with polio. Below, they answer questions about this new disease.

Q: What is the new illness?

A: Physicians around California have begun to observe a new type of acute flaccid paralysis, a disease in which patients quickly and permanently lose muscle function in an arm or leg. In some cases, patients have had respiratory symptoms before the paralysis begins. The disease resembles but is not the same as polio.

Q: How common is it?

A: This disease is very rare. About 20 cases have been identified in the U.S. so far, all in California, and all occurring in the past 18 months.

Q: What causes the new disease?

A: Doctors are not sure, but suspect it may be caused by a virus. Some of the children identified with this disease have had enterovirus-68, which is from the same family as the polio viruses. This virus is suspected in part because a similar type of paralysis caused by another enterovirus has been seen for many years in Asia and Australia. Another possibility is that the disease may be autoimmune.

Q: How are Stanford Medicine Children’s experts leading efforts to learn more about the disease?

A: We’ve written a report about five of the early cases, which Dr. Waubant will present at the annual meeting of the American Academy of Neurology in Philadelphia, April 26 to May 3. We are working with the California Department of Public Health (CDPH) to identify and track cases, with the goal of learning the cause of the disease. We want to temper the concern, because, at the moment, it does not appear to represent a major epidemic but only a very rare phenomenon. The CDPH is taking these reports very seriously. We hope our efforts will help us develop prevention and treatment strategies in the future.

Q: Does the polio vaccine protect children from the disease?

A: No, vaccination against polio does not protect against this new disease. However, there is also no evidence that the polio vaccine has any other connection to the disease, and it is still important for children to receive the polio vaccine.

Q: What should parents do if they suspect their child is affected?

A: All children who show symptoms of paralysis should be seen immediately by a doctor.