According to press reports 340 people were stricken with a "mysterious" sickness on the Sinfonia in Brazil last week. The sickness was described as causing severe diarrhea and vomiting.

Subsequent reports said Brazilian officials found problems with the amount of chlorine in the ship's drinking water and the storage of some perishable food items.

MSC Cruises has had no virus incidents for the past decade, according to a senior company executive, and its ships consistently score very high on U.S. Public Health inspections.