The first U.S. case of birth defects potentially linked to a mosquito-borne virus has been identified in Hawaii.
A baby born in Oahu with microcephaly, a condition marked by brain damage and a very small head, had previously been infected with Zika virus.
Zika virus has been linked to a surge in microcephaly in Brazil, where thousands of babies have been born with the condition in recent months.
The Oahu baby's mother lived in Brazil in May and was likely infected with the virus early in her pregnancy, the New York Times reports.
“We are saddened by the events that have affected this mother and her newborn,” Dr. Sarah Park, Hawaii’s state epidemiologist, said in a statement. “This case further emphasizes the importance of the C.D.C. travel recommendations released today.”
The virus is transmitted by the Aedes genus of mosquito. This includes Aedes egypti--an insect whose range stretches as far north as Georgia and South Carolina in the U.S.--and the Asian tiger mosquito, which is found throughout the Southeast.
Zika virus has largely been seen in more tropical locales, however. And the CDC has issued a travel warning to pregnant women for over a dozen countries including: Brazil, Colombia, Ecuador, El Salvador, French Guiana, Guatemala, Guyana, Haiti, Honduras, Martinique, Mexico, Panama, Paraguay, Saint Martin, Suriname, and Venezuela as well as Puerto Rico.
"Pregnant women in any trimester should consider postponing travel to the areas where Zika virus transmission is ongoing. Pregnant women who must travel to one of these areas should talk to their doctor or other healthcare provider first and strictly follow steps to avoid mosquito bites during the trip," the CDC said in a statement.
Meanwhile, how Zika might cause microcephaly is not yet understood and there is no absolute certainty that it's the virus that has caused the patterns of birth defects.
While other viruses are known to cause birth defects, Zika is part of a family of viruses not known previously to cause birth defects, notes NBC News.
While some babies with microcephaly in Brazil, like the Oahu infant, test positive for the virus, there is no easy test for it, making it difficult to make a definitive assessment.
Zika is not transmitted from person-to-person and experts said there are no fears currently of an outbreak in Hawaii. However, the virus is believed to spread much like dengue fever, which has become a problem in the Aloha State.
Zika is generally a passing, non-lethal infection in healthy people who are not pregant. The most common symptoms of Zika virus disease are fever, rash, joint pain, and conjunctivitis, according to the CDC.
The illness is usually mild with symptoms lasting from several days to a week. Severe disease requiring hospitalization is uncommon.