The Centers for Disease Control and Prevention is investigating more cases of children who have developed polio-like symptoms, possibly related to enterovirus D68.
Boston Children's Hospital said Tuesday that it has seen four patients between the ages of 4 and 15 with limb weakness, CBS Boston reports. One had a nasal sample that tested negative for enterovirus D68, and the other children's test results have not yet come in. One of the children has since been released from the hospital.
Dr. Mark Gorman of Boston Children's Hospital said at a Tuesday press conference that it appears to be a two-part illness where patients develop respiratory symptoms followed by neurological symptoms about two weeks later.
Ten cases have also been reported in Colorado, where children exhibited weakness in one or more limbs and an MRI showed distinctive findings in the central portion of the spinal cord.
It is not yet clear whether enterovirus D68 is causing the paralysis symptoms, but on "CBS This Morning" Monday, medical contributor Dr. David Agus explained there's reason to believe there may be a connection. "Polio is an enterovirus so we know enteroviruses can affect neurological symptoms. In fact there was an outbreak earlier this year in the state of California where several kids got paralysis and they also had this particular virus."
Doctors in both Boston and Colorado say they do not believe any of the children have polio; most were confirmed to be up to date on polio vaccinations.
In the Colorado cases, nine children showing paralysis symptoms last week were tested for enterovirus D68; four tested positive, four were found to have a rhinovirus or different strain of enterovirus, and the ninth case was unclear, the Denver Post reports. On Monday, Colorado health officials have confirmed a tenth case of paralysis-like symptoms in a child.
Dr. Larry Wolk, director of Colorado's Department of Public Health and Environment, said all 10 cases are being handled by Children's Hospital Colorado in Aurora. Six of the 10 children have been discharged from the hospital.
The cases come amid an unusual outbreak of enterovirus 68, which can cause severe respiratory illness in children. The virus started spreading in the Midwest in August and has since infected more than 470 people in 41 states and the District of Columbia.