[Updated 3/15/16, 7:16pm; corrected 3/16/16, 7:00pm. See below.] In the Luganda language, zika means “overgrown.” It’s also the name of the Ugandan forest where, in the mid-20th century, researchers discovered the now-notorious virus. Dense forest is an appropriate and vivid image for the latest global health threat. So much about the virus and its effects are new to us, obscured from view, but researchers are slashing away at the undergrowth to reach shafts of light.
The virus is spread by the bite of the Aedes mosquito, and possibly person to person through sex. From what we know so far, the danger to most adults is at worst like a mild case of flu. But in pregnant women, Zika seems to be invading the fetus’s brain and causing microcephaly, an abnormally small head due to stunted brain growth. The links between microcephaly and Zika are not ironclad but looking stronger by the week. Infection during the first trimester of pregnancy seems to contribute to the risk.
There is also growing evidence of a link between Zika infection and Guillain-Barré syndrome, a rare autoimmune condition that attacks the nervous system and, on occasion, can be life threatening.
Zika’s more sinister threat first drew notice from health officials in 2013, with an outbreak in French Polynesia. But few resources have been brought to bear until recently. For example, The National Institutes of Health until this year had spent nothing on Zika research, while budgeting about $97 million annually for work on its Flavivirus relatives such as dengue, West Nile, yellow fever, and Japanese encephalitis, said Anthony Fauci, the National Institute of Allergy and Infectious Disease (NIAID) director, in a January press briefing.
But the current outbreak, which started in Brazil in 2015, has coincided with more than 4,000 cases of microcephaly, well beyond the typical rate, and has spread northward through the Americas and the Caribbean. The scramble is on. Drugs, vaccines, and other interventions need to be developed and tested. NIAID has jumpstarted several programs using previous work on related viruses and says it is “possible” that a vaccine could be tested in humans before the end of 2016.
But products could be years away, which is cold comfort to people in harm’s way, unsure whether to forestall pregnancy—as some of their governments have recommended. (That is, if women even have that luxury. As the Economist recently noted, in many places where Zika infection has spread, so has debate over birth control and abortion policies.)
Recent weeks have brought developments that could accelerate progress toward a solution, although, as we’ll see, breakthroughs in such a new area of biological exploration inevitably come with risks that could blunt the momentum just as quickly.
Let’s start with a possible breakthrough in drug development. In a paper published last month, scientists at Adimab, in the distinctly un-tropical clime of Lebanon, NH, said they found powerful antibodies in a vial of blood from an Ebola survivor.
Those antibodies could potentially help people fight off Ebola infection. Led by senior scientist Laura Walker, the team said it did in six weeks what usually takes a year, found from 10 to 35 times as many antibodies as other similar experiments would find, Walker says.
Now they’re doing the same experiment with Zika. They have begun the work with blood samples drawn from three people in Brazil who were infected 14 months ago.
“This platform is applicable theoretically to any virus, as long as you have a blood sample from one or more patients with an antibody response,” says Walker.
With Ebola, they found 349 antibodies that the survivor’s immune system had produced to fight off the infection. Further testing at the U.S. Army Medical Research Institute of Infectious Diseases narrowed the field to a dozen or more super-potent antibodies, about 5 percent of the total from the sample. (It turns out not all antibodies in an immune response are created equal. A few are far more effective at stopping, or “neutralizing” an intruder–and those are the ones drug developers want to identify, clone, and perhaps modify as the basis of a medicine.)
Adimab has uploaded the sequences of the 349 antibodies into a public database. Anyone can work on them, and Walker and Adimab CEO Tillman Gerngross say parties already are moving the handful of super-potent ones into the drug development process. They won’t say who, but say they have been contacted with technical questions.
If Adimab produces similar promising results with its Zika work—which is no guarantee—it won’t throw the work into … Next Page »