New evidence suggests that the Zika virus could be linked to a rare serious neurological disorder.
Guillain-Barré Syndrome attacks the nervous system; in a matter of weeks healthy patients can be lying in an intensive care unit, unable to move.
Doctors saw an increase in the rare condition in French Polynesia shortly after the Zika virus was reported there.
Researchers looked at 42 people with Guillain-Barré in French Polynesia and found that 98 percent of them had antibodies to Zika, a sign that they had been infected with the virus. Eighty-eight percent of the GBS patients reported Zika symptoms including fever, rash and joint pain about a week before developing Guillain-Barré.
French Polynesia isn't the only place where the connection between GBS and Zika is suspected. Friday, the World Health Organization announced eight countries or territories saw an increase in GBS since last year. They include Brazil, Colombia, Venezuela and Puerto Rico.
Guillain-Barré Syndrome is rare. Between 3,000 and 6,000 Americans develop the condition each year, according to the CDC.
Patients feel tingling in their fingers and toes as their immune system begins to attack their nerve cells. Eventually paralysis develops. It isn't clear what caused GBS, but it is known to develop after various kinds of infections.
Patients usually recover, but it can take months, even years.