Zika Virus May Cause Alzheimer-like Symptoms in Adults

Even as Florida Gov. Rick Scott says South Beach has been identified as the second area of Zika transmission on the U.S. mainland (the first being Miami’s Wynwood arts district) a new study says the virus may affect more than the fetuses of pregnant women.

Zika is making headlines again after new evidence emerged that certain adult brain cells may be susceptible to the virus.

Among the ones that could be affected are cell populations that serve to replace lost or damaged neurons in the brain and are crucial to learning and memory. If Zika does, in fact, target these neural progenitor cells, it could result in the loss of said cells and reduce brain volume—similar to that seen in microcephaly cases with newborns. In an adult, this type of deficit is associated with cognitive decline and conditions such as Alzheimer’s disease and depression.

“Based on our findings, getting infected with Zika as an adult may not be as innocuous as people think,” said Joseph Gleeson, adjunct professor at Rockefeller, head of the Laboratory of Pediatric Brain Disease, and Howard Hughes Medical Institute investigator. “The virus seems to be traveling quite a bit as people move around the world. Given this study, I think the public health enterprise should consider monitoring for Zika infections in all groups, not just pregnant women.”

The new findings was published on August 18, 2016, in Cell Stem Cell.

Sujan Shresta, a professor at the La Jolla Institute of Allergy and Immunology, engineered a mouse model to mimic the Zika infection in humans. What she discovered proved interesting: fluorescent biomarkers illuminated adult brain cells that could indeed be attacked by the virus.

“It’s a complex disease,” Shresta said. “It’s catastrophic for early brain development, yet the majority of adults who are infected with Zika rarely show detectable symptoms. It’s effect on the adult brain my be more subtle, and now we know what to look for.”

Gleeson and his colleagues believe that adults with weakened immune systems are the most susceptible to the virus.

Zika, which has become widespread in Central and South America over the last eight months, has raised travel concerns across the globe, most recently in the southern US. Now, with these new findings, there’s a possibility of long-term effects in adults.

Quick Facts

According to the Centers For Disease Control and Prevention, the virus is mostly spread by a bite from an infected mosquito (of the Aedes species). These mosquitos are daytime biters, however they can still bite at night. You can also get Zika through sexual intercourse.

It can be passed from a pregnant woman to her unborn fetus. It can cause certain birth defects— most notably microcephaly, which may result in smaller-than-normal heads and development disabilities in newborns.

Currently, there is no vaccine or medication for Zika.

Prevention tactics include: wearing long sleeves and pants in high-risk areas, stay in places with air conditioning or screened windows and use insect repellant.