Researchers take next step in testing potential Zika vaccine

tries: Brazil, Mexico, Panama, Costa Rica and Peru.

Zika has caused an epidemic of birth defects — including babies with abnormally small heads and brains — in parts of Latin America and the Caribbean and continues to spread. For the U.S., the risk has largely been to travelers, although mosquitoes spread the virus in parts of southern Florida and Texas last year.

Zika largely disappeared from the headlines over the winter, but mosquito season is fast approaching — and the risk persists internationally.

“It is imperative that public health researchers continue to work to contain the spread of the virus,” Dr. Anthony Fauci, director of NIH’s National Institute of Allergy and Infectious Diseases, said Friday.

First-stage safety testing of a socalled DNA vaccine against Zika signaled no side effect concerns, Fauci said — allowing the NIH-created shots to progress to the next stage of testing that will help tell if they really work.

First, researchers will evaluate 90 healthy adults given different doses to determine the best one. Those volunteers will be tested at Baylor, the University of Miami and the Univer- sity of Puerto Rico.

Once the correct dose is picked, the larger part of the study could begin as early as June at those sites and additional ones in the at-risk countries — giving 2,400 volunteers either the experimental vaccine or dummy shots.

Don’t expect a vaccine to be widely available any time soon. If Zika causes lots of illness this year, Fauci said, researchers may have clues by early 2018 about how well the shots work — but if natural infections slow, they’ll need many more volunteers to get an answer.