Amid a surge of measles cases nationally, Orange County Health Care Agency officials Wednesday reported a confirmed case in the county. A young adult who had been traveling internationally was infected, officials said. “Anyone planning domestic or international travel — or hosting visitors — should be fully vaccinated at least two weeks beforehand,” said Dr. Anissa Davis, deputy county health officer. “Adults and others who are not immune remain at risk, especially as outbreaks continue across the country and worldwide. An infection can be spreading the virus four days before the rash is noticed.