Researchers have identified a potential treatment for Zika to protect both mothers and their unborn babies, and it may be ready for human use in as little as two years.
According to a study published Monday in the journal Nature, antibodies isolated from the blood of people who had been infected with Zika “markedly reduced” Zika infection in pregnant mice and their fetuses. At birth, there was less damage to the placenta, and newborn mice were larger than those whose mothers had not received the antibody treatment.
The study’s authors said that if the therapy is determined safe for use in humans, it could be given as a preventive measure for pregnant women in Zika-endemic areas. The therapy could also help pregnant women who are already infected and could be used in men to prevent sexual transmission to a partner.
According to Michael Diamond, co-senior author and professor at Washington University, there’s already a sufficient body of evidence that suggests antibodies protect against viruses like measles, mumps and rubella, the latter which can, like Zika, cross the maternal-fetal barrier and cause serious birth defects. The results are, therefore, unsurprising to infectious disease experts, said Diamond, but they still needed to be demonstrated.
“We didn’t know, for example, how potent an antibody needed to be,” said Diamond in an interview with Humanosphere. “Some viruses replicate more quickly than others, some viruses can sort of hide in different cells. So being able to establish that this level of protection can occur without any evidence of damage to the fetus is important.”
Diamond said researchers plan to test the antibody therapy in primates within the next six months. The overall process of approving the therapy for use in humans, he added, could take a minimum of two years.
“But the FDA can always accelerate things,” Diamond said. “They certainly did with Ebola … but I don’t think they would do it with this, because the risks of Ebola are quite different from the risks of Zika.”
Most people infected with the Zika virus are never aware they have it, but one in five will develop symptoms such as a mild fever, rash, joint pain or red, sore eyes. The infection has also been linked to a rare nervous system disorder, Guillain-Barré syndrome, that can cause temporary and sometimes permanent paralysis.
In pregnant women, however, Zika can cause severe birth defects such as microcephaly, where a baby is born with an abnormally small and underdeveloped skull. Most children with the condition face lifelong intellectual disability and development delays.
In addition to the antibody therapy, scientists have also been working to develop a vaccine that could protect people from ever contracting Zika. In the U.S., the FDA is trying to fight the spread of the disease using genetically modified mosquitoes.
Until a method of prevention or treatment is available, however, pregnant women with Zika are often faced with the difficult decision of whether or not to terminate their pregnancies. The epidemic has caused particular stress in Latin American countries that criminalize abortion or even birth control. To date, only Cuba and Uruguay have legalized abortion and made it widely available.