Zika infection found in eyes of mice – Study

Genetic material from the Zika virus is present in the tears of infected mice, which suggests the virus may linger in the eyes, researchers say.The discovery from tests on mouse fetuses, newborns and adults may help explain why some people infected with Zika develop eye disease that puts them at risk for permanent vision loss. What isn’t yet known is whether or not this Zika material in the eyes can transmit infection, and if it can do so in people, the researchers said.

Further studies on people infected with Zika are being planned, according to researchers at the Washington University School of Medicine in St. Louis. That’s because findings from animal studies don’t always turn out the same in people.

“Our study suggests that the eye could be a reservoir for Zika virus. We need to consider whether people with Zika have infectious virus in their eyes and how long it actually persists,” study co-senior Dr. Michael Diamond, a professor of medicine, said in a university news release.

About one-third of babies infected with Zika in the womb have eye problems. These problems can include inflammation of the optic nerve, retinal damage or blindness after birth, the study authors noted.

In adults, Zika can cause conjunctivitis -- redness and itchiness of the eyes. In rare cases, adults with Zika infection can develop a condition called uveitis, used to test anti-Zika drugs, the authors suggested.

The study was published Sept. 6 in the journal Cell Reports.

The Zika virus, which is usually mosquito-borne but may also be sexually transmitted, doesn’t pose a significant health threat to most people. But it can cause birth defects, including microcephaly, which leads to babies born with abnormally small heads and brains.

The vast majority of Zika infections have been in Latin America and the Caribbean. However, last month, two neighbourhoods in the Miami area reported cases of locally acquired infection.