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Watch the spread of Zika in the Americas in one terrifying GIF
Zika has rapidly gained a foothold in the Americas.
Starting with Brazil in May 2015 and accelerating quickly into 30 countries and territories so far, the outbreak of the untreatable Zika virus has prompted a lot of concern, primarily because of some of the worrying disorders that have been named as potentially linked with the virus.
We've created a GIF displaying all the places the Zika virus has spread through local transmission, meaning via mosquitoes, since the start of the outbreak, including the most recent travel advisories by the Centers for Disease Control and Prevention:
What is Zika virus?
The Zika virus is a mosquito-borne disease (meaning it passes from person to person via mosquito bite) that was discovered in the 1940s. It wasn't until 2007, when the first outbreak of Zika occurred, that the virus was considered a major threat to public health.
Once infected, only about one in five people with Zika ever shows symptoms, which most commonly include fever, rash, joint pain, and red eyes. That's why the main concern surrounds pregnant women, because there's been a spike in a brain condition called microcephaly in babies born to infected mothers in areas where the Zika virus is being locally transmitted. Researchers are also looking into the virus's potential connection to Guillan-Barre Syndrome, a temporary disorder in which the immune system attacks part of the nervous system.
Zika is carried by mosquitoes, namely the Aedes aegypti, a tropical bug that's great at transmitting diseases like yellow fever, dengue, and Zika. They are daytime mosquitoes, which means they bite during the day and like hanging out in warm, damp, heavily-populated locations.
Although the Zika virus is mostly transmitted when a mosquito bites a human infected with the virus, then goes on to bite another human, some rare cases of sexual transmission via semen have been documented in the past, and a person in Dallas, Texas recently got infected via sexual transmission.
What you need to know about Zika, as outlined by CDC director Tom Frieden:
Pregnant women in the US should hold off on traveling to Zika-infected areas.
Women should use protection or abstain from having sex with a male partner that just traveled where Zika is spreading.
Pregnant women who traveled to an area where Zika is spreading should be tested within 2 to 12 weeks of their visit.
Remember, this is a fairly new phenomenon, and there is still a lot we don't know. The last time a virus was linked to significant birth defects was half a century ago with the discovery of rubella, or German Measles.
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