First Zika Vaccine Now Entering Human Trials

Could this help curb the outbreak?

An experimental vaccine to combat the Zika virus has gained approval from the Food and Drug Administration to begin human testing, with the first individuals set to receive the vaccine in the coming weeks. 

The vaccine, GLS-5700, was developed through a cooperation between the South Korea-based GeneOne Life Science and Inovio Pharmaceuticals from Pennsylvania. While there are many Zika vaccines currently in development, this is the first to receive FDA approval to begin phase 1 testing in humans. In testing with small animals, the vaccine was successful in safely promoting antibodies against the virus.

In approximately three weeks, 40 healthy individuals who do not have the virus will receive the immunization. The primary purpose of this phase of testing is to learn about the drug's dosage safety, as well as any side effects that may occur. The preliminary results from the trial will be available later this year. 

Because FDA testing is a lengthy and thorough process, it will likely be several years before it is widely available for the general public, but the severity and prevalence of the virus may allow a useful medication to get through the red tape a little faster. 


If a healthy person is infected with Zika, they may experience symptoms of fever, rash, and muscle aches. That might not seem too bad, but the stakes are much higher when a pregnant woman is infected. Zika has been linked to several birth defects like hearing loss and stunted growth, with microcephaly being the most severe. 

In many South American countries where Zika is hitting the people hardest, strict laws prevent women from accessing contraceptives to prevent pregnancy or have an abortion when severe birth defects are detected. Currently, the CDC doesn't believe that Zika will affect future pregnancies once the active infection is over, but it will take time to fully understand any long-term effects that may exist.

The Zika virus is primarily transmitted via infected mosquitos, but it can be passed from human to human through bodily fluids like semen, saliva, and urine as well. A total of 62 countries have been affected by the Zika outbreak, with concerns that the Olympics this summer in Brazil — the origin of the epidemic — could dramatically increase that number. 

The sooner there is an effective vaccine available, the safer these pregnant women will be.

Cover image: Shutterstock


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