There is no vaccine or medicine for Zika, but the virus does have a natural enemy — antibodies created by the immune system’s response to infection.
Scientists long have known about the power of antibodies to neutralize viruses. But they faced a conundrum with Zika: A person has to be infected first before their immune system kicks in.
For pregnant women, who are at greatest risk from Zika because the virus can cause birth defects and neurological problems in the fetus, the key is to avoid infection in the first place.
On Wednesday, a team of scientists led by the University of Miami’s Miller School of Medicine reported a breakthrough. They stopped Zika from spreading to macaque monkeys by first injecting the primates with a mix of antibodies that had been cloned from the blood of an infected person.
It’s a promising step in the race to develop a therapy that will prevent and treat Zika, said David Watkins, a UM researcher who collaborated on the study, which was reported in the journal Science Translational Medicine.
“When there’s an outbreak of Zika,” Watkins said, “we need to protect the pregnant women, and this is the route we chose.”
For now, the best way to prevent Zika is to avoid bites from an infected Aedes aegypti species of mosquito. The virus also can be contracted from having sex with an infected person.
But if the research team can find a funder for a clinical trial of its experimental therapy, the findings reported Wednesday could lead to a treatment that would protect against Zika infection, said Diogo Magnani, a UM scientist who was the lead author of Wednesday’s article.
“Let’s say there’s an outbreak in Miami,” Magnani said. “We know that some populations might be more at risk than others, so you might want to prevent this.... Or you’re going to travel to an area that has an epidemic, you might want to take one of these shots before you travel there.”
The experimental therapy is not a vaccine, though, which typically works by injecting a weakened virus into a person to induce a natural immune response. Rather, the therapy uses a so-called cocktail of three antibodies that are especially effective at neutralizing Zika.
“Instead of each person having to create their own response, we now go and deliver the best response we can find,” Magnani said.