Travel restrictions are not needed within the continental United States for pregnant women out of concerns about the mosquito-born Zika virus, National Institutes of Health disease expert Dr. Anthony Fauci told CNBC on Monday. "There's no local transmission ... of the virus in the continental United States," he said in a "Squawk Box" interview. However, he said there have been local cases in Puerto Rico, the Virgin Islands, and American Samoa, in addition to South and Central America. "To tell someone not to travel within the continental United States is not true," Fauci said in response to reports that some doctors may be telling pregnant women not to go to places where mosquitoes are prevalent. Last week, the Centers for Disease Control and Prevention said it definitively concluded that an infection of the Zika virus in pregnant women causes of the birth defect microcephaly and other severe brain abnormalities in babies. "As we get into the summer months when there will be more robust mosquito involvement [in the U.S.], mosquito control becomes again becomes a very important issue," said Fauci, director of the NIH's National Institute of Allergy and Infectious Diseases. He said people in the continental U.S. should not be worried but should be "prepared" by using insect repellent and covering up.Zika Virus