Zika virus is primarily transmitted to humans by Aedes aegypti mosquitoes. However, in addition to mosquito-borne transmission, Zika virus infections have been reported through intrauterine transmission resulting in congenital infection, intrapartum transmission from a viremic mother to her newborn, sexual transmission, and laboratory exposure.
A total of 116 residents in the US have now been confirmed to have tested positive for the Zika virus, revealed a report by US Centers for Disease Control and Prevention (CDC).
"During January 1, 2015-February 26, 2016, a total of 116 residents of 33 US states and the District of Columbia had laboratory evidence of recent Zika virus infection based on testing performed at CDC," said the report released on Friday.
"One case occurred in a full-term infant born with severe congenital microcephaly, whose mother had Zika virus disease in Brazil during the first trimester of pregnancy," the report said.
The other 115 persons either reported recent travel to areas with active Zika virus transmission or sexual contact with such a traveler, showed the findings published in CDC's latest Morbidity and Mortality Weekly Report.
All 115 patients had clinical illness, with the most common signs and symptoms being rash (98%), fever (82%), and arthralgia (66%), the report added.
Before 2015, Zika virus disease among U.S. travelers was uncommon probably because of low levels of Zika virus transmission in travel destinations and limited disease recognition in the United States, the agency said.