It is sweeping across Latin America, Carribean and has reached China and Australia as well. Zika which circulated in primates for thousands of years has exploded in humans. Mercifully, the virus does not cause hemorrhagic fever or death. Not till now at least.

After largely being associated with shrunken brains in newborns, it is now linked to eye defects, progressive vision loss and even blindness in infants, a new study published in the Journal of American Medical Association (JAMA) Ophthalmology has found.

Zika Gets Deadlier

The JAMA study involved 29 newborns with small heads who were examined in Brazil and a third of them, that is 10, had retina damage in one or both eyes. The most common problems were black speckled lesions in the back of the eye, large areas of tissue damage in the retina or damaged blood vessels below the retina.

Exactly how much or how less these babies can see is not known at this point but doctors say that lesions in any part of the eye means damage. What’s worse, this damage is irreversible but the earlier the diagnosis is made, the better.

However, it is not clear whether a baby with a normal-sized head exposed to Zika in the uterus develops eye damage or not.

Zika symptoms show only in 20% of the cases, so doctors in the US are now advising all women who travelled to the Zika-hit Latin American countries in their pregnancies, to get their babies evaluated for the infection.

But before you panic, let’s remember that the study had its limitations - the sample size was small and all the cases were examined in only one hospital of Brazil.

What Makes Zika Tick?

In terms of slow detection and sluggish response, Zika is quite similar to Ebola. In both outbreaks, the vulnerable population which was least prepared to handle any health crisis was severely hit.

After the World Health Organisation was given flak for its lethargic response to the deadly Ebola outbreak, this time it was quick to label the Zika wave as an international public health emergency on February 1.

It remains to be seen whether WHO will effectively scale up international control, preventive or research mechanisms to prevent the ​unwarranted spread of the infection across the globe. But scientists in the US are racing to sequence the virus to understand what made a mild flu-like illness be linked to microcephaly and eye defects in newborns.

Right now, everything about Zika is a big unknown. To make vaccines, therapies, cures, the scientists have to first understand how the virus works. Scientists are designing experiments to answer questions like, “Does one develop immunity against Zika”, “How do the placenta cells react when the virus enters a pregnant woman’s body?”, “Is Zika any genetically different from dengue?”, “Has Zika undergone mutation to be associated with shrunken brains in babies?”

Scientists are working round the clock on this novel virus but there’s no way of knowing how long it will take.

Related Read: Should You Postpone Travel To Zika-Hit Countries and Other FAQs