French authorities on Wednesday held off a British cruise ship with more than 1,700 passengers and crew, after an elderly man died onboard and dozens suffered a stomach illness. The vessel Ambition was midway through a 14-night voyage that began in Belfast and Liverpool. It had planned stops in northern Spain and along France's Atlantic coast. By the time the vessel reached Bordeaux on Tuesday evening, the stomach bug had already spread. The ship's operator, ‌Ambassador Cruise Line, said that sanitation and prevention protocols had been immediately implemented to prevent the spread. Authorities have ruled out norovirus, a highly contagious form of gastroenteritis which causes vomiting and diarrhea, but secondary tests are still ongoing to find out what cause the passengers to become ill. Food poisoning has not been ruled out, authorities said.…