Infectious disease experts and Long Island doctors held a Zika virus symposium Monday afternoon at South Nassau Communities Hospital in Oceanside.

Federal health officials say, so far, no one has contracted the mosquito-borne virus in the continental U.S. All U.S. cases, including several on Long Island, involved people who had traveled to other countries.

But the National Institutes of Health has said that outbreaks in the U.S. could be possible by this summer.