US: Health officials identify first birth defect from mosquito-borne disease Zika

The first birth defect linked to the Zika virus has been discovered in the US after a woman in Hawaii gave birth to a baby girl with microcephaly, the condition of an unusually small brain and head.

Health officials are concerned that the extremely dangerous Zika virus believed to be responsible for thousands of babies with microcephaly in Brazil could spread in similar warmer climates in the US such as in Hawaii and the American South.

The virus had already been identified in Puerto Rico and recently in Texas in a man who had travelled from El Salvador, another nation that has been suffering the effects of Zika among its newborns.

The mother in Hawaii — who had lived in Brazil last year — was likely to have been infected early in her pregnancy before leaving for Hawaii, CNN reported.

In a statement, Hawaii's health department said: "The mother likely had Zika infection when she was residing in Brazil in May 2015 and her newborn acquired the infection in the womb."

The US Centers for Disease Control are now advising pregnant women, or those planning to get pregnant, to avoid travelling to areas that have been hit by Zika which includes significant parts of South and Central America. There have also been outbreaks on the islands of Haiti, Martinique, and Puerto Rico.

"We are saddened by the events that have affected this mother and her newborn," Sarah Park, Hawaii's state epidemiologist, said in a statement. "This case further emphasizes the importance of the CDC travel recommendations."

The Zika virus, carried mainly by the Aedes aegypti mosquito, has caused particular concern because symptoms are often so mild, people do not bother reported them to a doctor. However there can be tragic consequences if a woman passes the disease onto her baby. More than 3,500 cases of microcephaly, including 46 infant deaths, could be linked to Zika in Brazil.

So far, there are no known cases of transmission within the US. Six Hawaii residents are known to have had the virus since 2014, but all picked it up through travel elsewhere.

Hawaii is currently experiencing an outbreak of dengue fever, transmitted by the same mosquitoes that can transmit Zika.