The Zika virus, a mosquito-borne illness that has been linked to a rise in birth abnormalities in Brazil, could spread to all but two countries in the Americas, the World Health Organization announced on Monday. Thus far, 21 countries in the Americas have been affected by the Zika outbreak, since the first case was reported in Brazil in May 2015.

Centers for Disease Control and Prevention - cdc.gov

Zika virus has ravaged regions of South America in recent months, and while symptoms are considered relatively mild (fever, rash, joint pain, and red eyes), the disease could pose serious risks for children born of pregnant, infected mothers. While a definitive link has not been established as of yet, experts believe that Zika virus could cause children to be born with abnormally small brains, a rare condition known as microcephaly. There is currently no treatment or vaccine available for the disease.

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"Aedes mosquitoes — the main vector for Zika transmission — are present in all the region's countries except Canada and continental Chile," WHO's regional office for the Americas said in a statement.

Wikimedia - wikimedia.org

The troubling status update comes less than a week after a baby with birth defects associated with the Zika virus was born at a Hawaii hospital — the first such case to appear in the U.S. — raising concerns about the international transmission of the tropical disease. Health officials in the state say the mother likely contracted the Zika virus while living in Brazil last year; there have been more than 3,500 reported cases of microcephaly in the country since October alone, the BBC reported.

The Centers for Disease Control and Prevention issued a "first-of-a-kind" travel alert on January 15, advising women of childbearing age in the U.S. to stay away from the following countries: Brazil, Colombia, El Salvador, French Guiana, Guatemala, Guyana, Haiti, Honduras, Martinique, Mexico, Panama, Paraguay, Saint Martin, Suriname, Venezuela, Puerto Rico, Barbados, Bolivia, Ecuador, Guadeloupe, Saint Martin, Guyana, Cape Verde, and Samoa.

Women in Colombia, Ecuador, El Salvador, and Jamaica, which have already experienced Zika outbreaks, have been told to avoid getting pregnant entirely.

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"It’s spreading really fast," Scott Weaver, the director of the Institute for Human Infections and Immunity at the University of Texas Medical Branch in Galveston, told Vox. "I think [the Zika virus] is going to be knocking on the doorstep in places like Florida and Texas probably in the spring or summer."

World Health Organization - paho.org