Brain lesions in the fetus of one pregnant pigtailed macaque infected with the Zika virus (ZIKV) are reported in a paper published online in Nature Medicine this week. The findings represent the first case of fetal brain injury in a nonhuman primate infected with ZIKV.
Previous research has established a nonhuman primate model of ZIKV infection; however, the brain abnormalities observed in the fetuses of infected pregnant women, such as microcephaly, have not yet been reported in animal models of ZIKV infection.
In an effort to develop a more representative animal model of ZIKV infection, Kristina Adams Waldorf, Michael Gale Jr., Lakshmi Rajagopal and colleagues infected a pigtailed macaque with ZIKV during the third trimester of pregnancy. Although the pregnant animal did not show signs of disease, such as rash or fever, the fetus developed brain abnormalities (which were not seen in a control fetus) within 10 days of infection and showed evidence of slower brain growth. Although the results are limited to one animal, the authors suggest that the pigtailed macaque may be a useful model for studying the progression of ZIKV infection in humans and testing candidate therapeutics or vaccines.