Monkeys infected with Zika virus are protected from future infection, and pregnancy dramatically prolongs infection in monkeys, findings that could help in fighting the virus in people, UW-Madison researchers said Tuesday. Scientists on campus have infected 13 rhesus macaque monkeys with Zika, a virus that has caused an outbreak involving severe birth defects such as brain damage in Latin America and the Caribbean. The UW-Madison scientists, in publishing the first findings of their study in the journal Nature Communications, said six monkeys injected with the virus twice, 10 weeks apart, became infected the first time but not the second time. That is apparently because their immune systems, trained by the first infection, warded off the subsequent challenge. “We found complete protection,” said Dawn Dudley, an associate scientist at the university and first author of the study. “This is a key finding because it means a vaccine could be quite effective against the virus.”
The researchers plan to study whether infection with dengue virus, carried by the same mosquitoes that harbor Zika, increases susceptibility to Zika or vice versa, O’Connor said. They also may look closer at how much the level of virus in a mother’s blood is related to the severity of damage to the fetus. It could be that drugs or a vaccine during pregnancy might minimize birth defects.