File under: the last thing we need right now. A mysterious virus whose onset, complete with paralysis and respiratory problems, mimics that of polio, has infected a small group of California children in the last two years, including a 4-year-old Berkeley girl, and a Stanford doctor has been leading the research into its origin and identity. As the LA Times reports, Dr. Keith Van Haren, a pediatric neurologist at Stanford University's Lucile Packard Children's Hospital, has been working with the state Department of Public Health, says, "We know definitively that it isn't polio," but they haven't determined what it is. Polio was eradicated in this country decades ago, and none of the infected children had traveled abroad.

According to CA Department of Public Health investigator Carol Glaser:

The afflicted kids suffer severe weakness or paralysis, which strikes rapidly — sometimes after a mild respiratory illness. Scans of the patients' spinal cords show patterns of damage similar to that found in polio sufferers, Glaser said. Two of the affected children tested positive for enterovirus-68, a virus that is usually associated with respiratory illness but which has been linked to polio-like illnesses as well.

Dr. Van Haren notes that instances of the virus still appear very, very rare. CNN reports that five children have been infected with what they're calling a non-polio enterovirus, but Van Haren told the LAT he knew of about 20 cases. Those include his Berkeley patient, 4-year-old Sofia Jarvis, who lost use of her left arm following an asthma-like illness in late 2012.

Parents should not be overly concerned, but frequent hand-washing and avoiding contact with the sick are the only known preventative measures at this time. Van Haren will be presenting a paper about five cases of the virus at the American Academy of Neurology's upcoming annual meeting in Philadelphia.

[LA Times]