How Zika Virus Might be Linked to Guillain-Barré Syndrome

New research indicates Zika virus might cause neurological disorder.


The Zika virus has been in the news a lot lately. Now a study indicates another newsworthy issue.

A study from French Polynesia found that people with Guillain-Barré syndrome were also more likely to have had a Zika virus infection.

"These patients tended to deteriorate more rapidly than we usually see with Guillain-Barré," lead author Arnaud Fontanet, MD, DrPH, said in an interview with BBC News. "But once they were over the acute phase of the illness their recovery tended to be better."

Dr. Fontanet is a medical epidemiologist and professor at the Institut Pasteur in Paris.

Zika is a virus spread by the Aedes mosquito, which is common in populated areas of South America, Asia, Africa and the southern US. The mosquito breeds in water and can do so even in very small containers or puddles.

Although the the Zika virus can infect humans, in most cases it is mild and many people don't even know they have the disease. Typical symptoms include a fever, rash and sore joints.

Guillain-Barré syndrome (GBS) is a neurological disorder that usually follows an infection. The Centers for Disease Control and Prevention (CDC) reports that GBS often occurs days or weeks after the infection and that at this point, scientists don't know what actually causes GBS.

Several different organisms have been linked to GBS, including influenza viruses. The organisms seem to cause the immune system to damage nerves. Like polio, GBS can cause weakness and paralysis.

Even those patients who recover often have permanent nerve damage, and recovery can take months or years. In the US, the CDC noted the estimated rate of GBS is one to two cases per 100,000 people each year.

Dr. Fontanet and researchers in French Polynesia studied two groups of patients. The first group had an illness with fever, the second group had Zika but no neurological problems. Forty-two of the patients developed GBS.

The scientists found that 98 percent of the patients with GBS had antibodies to the Zika virus. High antibody levels indicate the patient had an infection and the body tried to fight it. Most patients developed symptoms of GBS within six days of becoming infected with Zika.

Based on this study, Dr. Fontanet and colleagues estimated that one in every 4,000 people who are infected with Zika may develop GBS.

The study was published in the February issue of The Lancet.

The study was funded by Labex Integrative Biology of Emerging Infectious Diseases, the EU 7th framework program PREDEMICS and the Wellcome Trust.

None of the authors reported a conflict of interest.