Scientists clone Zika virus in step toward vaccine
LONDON — Scientists have for the first time cloned the Zika virus, a development that could bring a desperately needed vaccine within closer reach.
The mosquito-borne virus — which can also be sexually transmitted — has torn through Latin America in recent months, bringing an increase in microcephaly, a condition in which babies are born with abnormally small heads and underdeveloped brains.
A team from the The University of Texas Medical Branch at Galveston was able to genetically engineer Zika, so researchers can now make the virus in test tubes and on Petri dishes, according to a study (PDF) published Monday.
Lead author Pei-Yong Shi said his team’s manmade Zika means scientists can study and adapt the virus to develop a vaccine. It could also be used to test the efficacy of their own vaccines.
The team was able to infect mosquitoes with the cloned virus as well as mice, which went on to develop neurological diseases.
“What we’ve created is something that is reproducible, meaning that batches of this virus can be made in large quantities,” Shi said.
He said that if scientists are able to adapt the virus to make a safe vaccine, trials on animals could start soon and clinical trials could start as early as next year.
“But of course this will depend on whether we see serious side effects. We don’t even know yet what the full impact of Zika is, besides microcephaly and some other neurological diseases,” Shi said.
Some scientists have been researching the virus in mouse models to learn more about how it behaves and how it leads to devastating neurological deficits. The hope there too is that this is a starting point toward the development of a treatment and vaccine.
Several scientists welcomed the development, including Arturo Reyes-Sandoval, an associate professor at Oxford University’s Jenner Institute, who is working on a Zika vaccine. He said the new cloned virus would enable his team to better test its efficacy.
“The Zika virus took all of us by surprise, and one of the difficulties in developing preventative measures has been the lack of tools available to test the vaccine. So a development like this will help for sure,” Reyes-Sandoval said.
While several teams of scientists are working on Zika vaccines, this is the first time the Zika strain has been replicated.
The U.S. National Institute of Allergy and Infectious Diseases has created a trial vaccine for similar viruses that can be used as a starting point for a Zika vaccine, and the Jenner Institute has conducted trials with mice and aims to hold clinic trials by 2017.
The virus has caused panic across the Americas, with some countries advising women to hold off on getting pregnant.
The World Health Organization says Zika is also linked to Guillain-Barré Syndrome, a rare disease in which a person’s own immune system damages the nerve cells, causing muscular weakness and, in some cases, paralysis.
Some scientists fear that the impact is greater than initially thought, linking the virus to premature births, eye problems and several neurological conditions in babies born to infected women.
A pharmaceutical company and condom manufacturer announced that they would arm the Australian Olympic team with “Zika-proof” condoms and antiviral lubricants as thousands of athletes compete in the Summer Games in Brazil, the epicenter of the latest Zika outbreak.
Some health experts have called for the Olympics to be moved to a Zika-free location