Zika virus warning accompanies Obama to Cuba

President Obama's historic trip to Cuba on Sunday was accompanied by a warning from U.S. health officials that the mosquito-borne Zika virus linked to birth defects has spread to the island nation.

The Centers for Disease Control and Prevention issued a travel alert Saturday that "mosquitoes in the area are infected with Zika virus and are spreading it to people."

The "level 2" travel alert that calls for enhanced precautions, although the CDC recommends that pregnant women not travel to Cuba at all. Precautions include avoiding mosquito bites by using repellent and wearing long sleeves and other clothes to protect the skin.

Sexual transmission of Zika virus from a male partner is also possible, so travelers are encouraged to use condoms or not have sex.

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An entourage of hundreds, including staff and media, joined Obama on his trip, the first visit from a U.S. president since Calvin Coolidge in 1928. The visit is part of Obama's effort to improve relations and trade with Cuba, both of which have been severely restricted by a decades-long U.S. embargo targeting the communist regime.

The Zika virus, linked to an epidemic of birth defects in Brazil, is spreading quickly throughout Latin American and the Caribbean. The defects included microcephaly, a brutal condition in which babies are born with unusually small heads and incomplete brain development. There is no specific treatment for the disease, which can limit overall development and shorten life expectancy.

The National Center for Atmospheric Research issued a report last week saying the Zika outbreak could be headed to the U.S this summer.

"The Aedes aegypti mosquito, which is spreading the virus, ... will likely be increasingly abundant across much of the southern and eastern United States as the weather warms," the research center said. "Summertime weather conditions are favorable for populations of the mosquito along the East Coast as far north as New York City and across the southern tier of the country as far west as Phoenix and Los Angeles."