A Carnival Cruise Lines ship returned to Galveston from a five-day cruise to Mexico with more than 300 people sick with a gastrointestinal illness. Carnival said preliminary tests showed the outbreak might have been caused by a norovirus.
The Celebration left Galveston on Monday. On Wednesday, Carnival contacted the Centers for Disease Control and Prevention to report an unusual number of ill passengers.
By Friday, 297 of 1,576 passengers and 19 of 689 crew members were ill, according to the CDC.