Last year the US saw an outbreak of enterovirus D68, which affects the respiratory system. The symptoms are much like those of a regular cold at first, but progress more quickly and can lead to wheezing and difficulty breathing. The virus was reported in small numbers until last year, when there were 1,153 confirmed cases of “respiratory illness” caused by the virus between August 2014 and January 2015.
Now it seems one strain of the virus may have caused paralysis in some children, according to a study in the Lancet Infectious Diseases. Researchers at the University of California, San Francisco examined the clinical samples and charts of patients, mostly children, who had become partially paralyzed with something called “acute flaccid myelitis.” About half had the enterovirus, and researchers blamed a strain, B1, which has some resemblance to the virus that causes polio.
The B1 strain appeared only in 2010, the researchers wrote. “I don’t think it’s coincidental that it’s around the time the first cases were described,” the study’s lead author, Charles Chiu, told the New York Times (paywall).
As the Washington Post notes, “While the research does not provide a definitive link—that would only be established if the virus were found in the spinal fluid and it was not—it provides the strongest evidence to date of the link between enterovirus D68 and paralysis.”
The researchers also found that the virus doesn’t guarantee paralysis. Two of the affected children were siblings with the same strain and both had colds, but only one suffered paralysis. This suggests that other environmental or immunological factors might play a role in causing the paralysis, the authors wrote.
It’s hard to protect against the virus, as there’s no current vaccine. The best thing parents can do is keep their infected children from going to school, keep them rested and hydrated, and go to the doctor if they see extreme wheezing or coughing, according to Pia Pannaraj, an infectious-diseases specialist at Children’s Hospital Los Angeles.