A mountainous Caribbean island nation has become the latest to be hit with a Zika travel advisory.

On Tuesday, March 22, the CDC added Dominica to its list of countries and territories with local transmission of the virus. The agency added Cuba on Saturday, March 19.

The virus, transmitted mainly via mosquitoes, has been identified in the US but only in people who've recently traveled to Zika hot spots. Once infected with Zika, only about 20% of people ever show symptoms, which most commonly include fever, rash, joint pain, and red eyes. There is no vaccine or treatment available for the virus. One reason Zika is troubling is because it has been linked with birth defects in babies whose mothers have had Zika symptoms and a neurological condition called Guillain-Barré Syndrome.

Here are all 39 countries and territories where local transmission of the virus has been reported as of Tuesday, March 22:

BI Graphic_Zika Virus_March 22_2016

To show just how rapidly how this virus had gained a foothold in the Americas, we've also created a GIF displaying all the places the Zika virus has spread through local transmission since the start of the outbreak:

via GIPHY

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