Some interesting developments:
"‘No room for doubt': New science proves Zika causes microcephaly"
“Although there is a strong scientific consensus that Zika virus is a cause of microcephaly, the early findings from this case control study are the missing pieces in the jigsaw in terms of proving the link,” said Laura Rodrigues, an infectious disease expert at the London School of Hygiene & Tropical Medicine and an author of the study.
“The evidence was very strong before this, enough to get a conviction out of most juries,” he said about Zika and microcephaly. “Now they have essentially found the gun in the defendant’s glove compartment. There is overwhelming evidence and there is really no room for doubt.”
The study included 32 infants born with microcephaly between January and May 2016 at eight hospitals in Recife, Brazil, and 62 babies without microcephaly born the following morning. The mothers in both groups had similar characteristics. Most mothers had Zika virus infections. Although many mothers also had other infections, such as dengue, those infections weren't associated with microcephaly in the study, and there was no significant difference between the mothers of the two groups.
Researchers found that about half of the babies with microcephaly had laboratory-confirmed Zika infections in their blood or spinal fluid. By comparison, none of the babies in the healthy control group tested positive for Zika.
And "Research reveals how Zika virus arrests fetal brain development in pigtail macaque"
"Our results remove any lingering doubt that the Zika virus is incredibly dangerous to the developing fetus and provides details as to how the brain injury develops," noted Dr. Kristina Adams Waldorf, the lead author of the study. She is a UW Medicine physician and researcher, and a University of Washington professor of obstetrics and gynecology who specializes in maternal and fetal infections.
"This is the only direct evidence that shows that the Zika virus can cross the placenta late in pregnancy and affect the fetal brain by shutting down certain aspects of brain development" Gale explained that the study results met Koch's Postulate, which establishes the criteria for determining if a microorganism is a causative agent for a disease or disorder.
"We were shocked when we saw the first MRI [magnetic resonance image] of the fetal brain 10 days after viral inoculation. We had not predicted that such a large area of the fetal brain would be damaged so quickly," Rajagopal noted. "Our results suggest that a therapy to prevent fetal brain injury must either be a vaccine or a prophylactic medicine taken at the time of the mosquito bite to neutralize the virus."
She added, "By the time a pregnant woman develops symptoms, the fetal brain may already be affected and damaged."
More on the monkey study:
Starting this past March, when the horror of Zika-induced birth effects was just becoming clear, the group launched an experiment that infected a pregnant, 9-year-old pigtail macaque with the virus.
The monkey mother showed no signs of illness, but very quickly — within 10 days of infection — the fetus developed brain damage similar to that seen in human babies affected by Zika.
“When I was watching the images come up for the first fetal MRI, we didn’t know what to expect,” said Adams Waldorf. “But the moment we saw the first fetal brain lesion, we knew we were re-creating the fetal brain-disruption sequence.”
The pigtail macaque is ideal. It’s known to be susceptible to flaviviruses like Zika, and its pregnancies are similar to those in people, the study noted.
Additional experiments are continuing. Another pregnant monkey and fetus have been infected and examined, but the results weren’t available in time for publication.
Eight other Zika-infected animals are now being observed, Gale said.
The new study also shows that any therapy for Zika will have to focus on preventing infection, Adams Waldorf said. The damage to the fetus occurred so quickly after infection, within days, that there’s no window for intervention after the fact.
“It’s going to have to be a vaccine or a prophylactic,” she said.